InfoBriefe 2001 – 2010

2023
Files
InfoBrief 2001-4
InfoBrief 2001-3
InfoBrief 2001-2
InfoBrief 2001-1
Author(s)
Hans-Joachim Huebschmann
Publication
Hans-Joachim Huebschmann, „Automated Sample Preparation: Methods for GC-MS and LC-MS“, 480 pages, Wiley-VCH, February 2022.
Print ISBN: 978-3-527-34507-6
eBook ISBN: 978-3-527-81752-8
Automated Sample Preparation: Methods for GC-MS and LC-MS | Wiley

2021
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Abstract
The automated injection to gas chromatography systems (GC) is most probably the widest use of the so called “autosamplers” for quantitative GC and its hyphenation to mass spectrometry (GC-MS). While simple autosamplers do sequence controlled injections only, the usage of robotic sample preparation systems like the PAL Systems work in an integrated fashion with GC and GC-MS systems. High precision for quantitative analysis is provided with excellent quality by the PAL System for every modern GC. The PAL System offers two liquid injection modes referred to as “Normal” for best quantitative performance, and “Fast” for high boiling matrix samples. This technical note describes the operation of the most widely used “Normal” injection mode for best quantitative precision data on any GC model equipped with a hot split/splitless injector.
Files
Highly Precise GC Injection with the PAL System – Whitepaper
Author(s)
Gwen Lim Sin Yee, Hans-Joachim Hübschmann, CTC Analytics Pte. Ltd., Singapore
Publication
PAL System, GC Application Note, Highly Precise GC Injection with the PAL System, 2021, CTC Analytics AG
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Abstract
A fully automated quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and extract clean-up method for gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS) analysis is presented using an industry standard robotic x,y,z-sampling system. This article analyzes organophosphate pesticides from orange juice. The automated workflow used in the study includes the extraction with acetonitrile and salting out and using a μSPE cartridge for matrix cleanup prior to injection into a gas chromatography–tandem mass spectrometry (GC–MS/MS) system. The method validation techniques, such as pre-spike and post-spike, were fully integrated into the automated workflow. Calibration linearities of the organophosphate pesticides in orange juice matrix range from 1 to 100 ng/mL with a precision achieved better than 0.995 for all compounds. By spiking 10 ng/mL of pesticides into the orange juice samples, recoveries were obtained in the range of 70–115%, while the precision from pre-spike (n = 7) and post-spike (n = 6) under the same concentration was less than 10% RSD. The calculated method detection limits (MDLs) of the monitored pesticides were in the range of 1.8–4.1 ng/mL, which are well below the regulated maximum residue limits (MRLs) of 10 ng/g for these pesticides.
Files
Chong Huebschmann – 2021 – Fully Automated QuEChERS Extraction and Cleanup
Author(s)
Chiew Mei Chong, Hans-Joachim Huebschmann
Publication
LCGC, Special Issues, Special Issues-04-01-2021, Volume 39, Issue s1, Pages: 12–16

2020
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Abstract
Purpose: Provide highly comparable data. Keep the sample integrity for metabolomics biomarker analysis by a highly reproducible and automated workflow for the two-step derivatization reactions used in GC-MS. Reduce the complexity of the manual operation and increase the sample throughput for unattended 24/7 operation. Methods: A standardized automated workflow is suggested using a regular industry-standard x,y,zrobotic system for the individual derivatization steps at different reaction temperatures. The reagent addition, timing of the derivatization steps and analysis are controlled by the robotic system. The derivatization procedure follows the well-established and globally applied protocols. Results: The automated derivatization workflow is executed in parallel to the chromatographic analysis by GC-MS. All samples are treated on the same time scale without waiting for analysis. The injection to GCMS is executed right after completion of the derivatization steps.
Files
Metabolite Profiling by Automated Methoximation and Silylation Metabolomics
Author(s)
Chiew Mei Chong, Hans-Joachim Huebschmann
Publication
Poster at the online Metabolomics Conference 2020, CTC Analytics Pte. Ltd.
https://doi.org/10.13140/RG.2.2.29085.03045
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Abstract
Objective: Develop an automated clean-up method with high recovery and sufficient clean-up for GC-MS. Methods: The automated sample preparation workflow presented involves an x,y,z-robotic autosampler. Mini-SPE cartridges comprising the clean-up sorbent for all spice matrices are used. Spice samples were extracted by using QuEChERS. The raw extract is placed into the autosampler vial for automated mini-SPE clean-up in parallel to online GC-MS/MS analyses. For an efficient clean-up, three different sorbent compositions were compared along with various automated workflows. Results: Commonly used pesticides found in spices were used for method development. For the relatively simple matrixes (e.g., coriander, cumin, and cardamom) the LOQ achieved was 10 ng/g. in the more complex matrixes of e.g., turmeric, chili powder, and black pepper an LOQ of 10 ng/g for around 77% of the compounds was achieved. The remainder of the compounds had satisfactory recoveries at 20 ng/g and higher levels. Highlights: The study describes the effectiveness of the automated mini-SPE clean-up in multiresidue analysis of pesticides in a range of spice matrixes. The clean-up cartridge uses one standardized sorbent mix for all spices. The mini-SPE clean-up can be automated and executed in few minutes only in parallel to an ongoing GC-MS/MS analysis for improved productivity. The method facilitates high- throughput residue analysis in compliance with the regulatory requirements of sensitivity and method performance.
Author(s)
Arnab Goon, Raviraj Shinde, Bappa Ghosh, Kaushik Banerjee, Hans-Joachim Huebschmann
Publication
Poster at the EPRW 2020 online, CTC Analytics AG, Zwingen, Switzerland.

2019
Abstract
Since the first publication in 2003 the QuEChERS extraction method for pesticides in food (Anastassiades 2003) became a worldwide standard. While the extraction step is well standardized (AOAC 2007.1; CEN 15662), the clean-up of the resulting extracts from different matrices is still in active discussions. A well proven solution for a unified clean-up for all food matrices with only one cartridge type has been established with the use of µSPE cartridges (Hayward 2016).
Author(s)
Jianxia Lv, Hans-Joachim Huebschmann, Günter Boehm, and Reto Bolliger
Publication
Poster at the RAFA conference Prague, CTC Analytics AG, Zwingen, Switzerland. Poster at the Separation Science Conference, 1./2. Nov 2017, CTC Analytics AG, Zwingen, Switzerland.
Abstract
Analyzing polycyclic aromatic hydrocarbons (PAHs) in drinking water becomes challenging especially for hard water (high mineral content water) and/or when sodium thiosulfate being added for treating chlorine content in drinking water during analysis. In this article, repeatability for determination of PAHs in drinking water using SPME Arrow (PDMS) immersion technique with gas chromatography mass spectrometer (GC/MS) was carried out. Single SPME Arrow had been used in this experiment to determine its durability. The repeatability (n=100) which characterized as %RSD was less than 10.93% for all analytes, ranged between 1.74 % – 10.93 %. The relative peak area of the 100th injection against the 1st injection peak area for all analytes ranged between 0.600 to 0.947; indicating SPME Arrow fiber is dutiful for at least 100 injections with immersion technique. In conclusion, fully automated SPME Arrow immersion technique with GC/MS analysis is an excellent option to analyze PAH compounds in drinking water; with higher throughput and robustness.
Author(s)
Gwen Yee Sin Lim, Thomi Preiswerk, Hans-Joachim Huebschmann, Chiew Mei Chong, Günter Böhm
Publication
Poster at the RAFA conference, CTC Analytics AG, Zwingen, Switzerland.

2018
Abstract
Among these studies, extractables and leachables represent a huge portion of the work the analyst does to characterize the substances potentially leaching into the product. The terms “extractables” and “leachables” are well defined by industrial working groups, 3, 4 mixed working groups5 (such as the Product Quality Research Institutione, the Leachables and Extractables Working Group, including pharmaceutical development scientists representing industry, health agencies, and academia) and subject experts.
Author(s)
Bénédicte Gauriat, Isabelle Froger, Damien Chevaillier, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific, Application Note 10398

2017
Abstract
The extraction and clean-up of pesticides from food still raises particular challenges due to the high number and difference in chemical nature of the compounds embedded in food matrices of high complexity and highly varying compositions. Due to their polarity, molecular weight, stability, or ionization characteristics compounds are detected by GC and LC separation typically using MS/MS or accurate mass instrumentation (Raina 2011; Scherbaum 2008) In recent years the QuEChERS (Quick Easy Cheap Effective Rugged Safe) methodology (Anastassiades 2003) has been introduced in many food safety laboratories for pesticides. While the extraction step has been well standardized (AOAC 2007.1; CEN 15662) the clean-up of the resulting extracts still differs widely for different matrices and laboratories with the common goal to extend the GC, LC and MS maintenance cycles for increased productivity (Jiao 2016), and reducing matrix effects. The potential for high sample throughput using the QuEChERS extraction is impeded by laborious maintenance work (Hildmann 2014; Stahnke 2012).
Author(s)
Hans-Joachim Huebschmann, Reto Bolliger, Guenter Boehm, Bruce D. Morris, Richard B. Schriner
Publication
Poster, Agilent Workshop Manchester, UK
Abstract
Metabolomic analysis is prone to technical errors at different states of sample preparation (e.g. extraction, purification, derivatization). Therefore, reproducible sample preparation is vital for ensuring reproducible and reliable results. Additionally, sample preparation has historically been a time-consuming challenge and a crucial bottleneck in the whole analytical process. It is desired to develop a method for reproducible, reliable and labor and time-saving sample preparation. Application of robotic platform to automation of sample preparation is a promising approach in this direction. Herein, we developed an automated sample preparation protocol based on a robotic platform PAL RTC (CTC Analytics AG, Zwingen Switzerland), which represent a modified Bligh and Dyer method producing samples for both hydrophilic metabolomics using GC-MS and lipidomics using SFC-MS simultaneously.
Author(s)
Yuki Soma, Toshiyuki Yamashita, Masatomo Takahash, Kuniyo Sugitate, Takeshi Serino, Hiromi Miyagawa, Kenichi Suzuki, Takatomo Kawamukai, Teruhisa Shiota, Kayoko Yamada, Hans-Joachim Huebschmann, Yoshihiro Izumi, Takeshi Bamba
Publication
Poster #362 at the 13th International Conference of the Metabolomics Society, Brisbane, Australia.
Abstract
Amino acids, sugars, and their analogues are indispensable targets in the investigation of molecular evolution in the primitive earth leading the protometabolism. Radiolysis is one of the effective mechanisms generating biomolecular building blocks from smaller molecules, however diverse byproduct formations disturb the pseudo-targeted analysis. Analysis by SPME extraction and on-fiber derivatization.
Author(s)
Yayoi Hongo, Kayoko Yamada, Hans-Joachim Huebschmann, R. Yi
Publication
Poster presentation at the Goldschmidt Conference 2017
Abstract
3-Monochloropropane-1,2-diol (3-MCPD), 2-monochloropropane-1,3-diol (2-MCPD) and glycidol known as contaminants in foodstuffs. MCPD fatty acids may occur during the refinement process of oils and fats at high temperature in the presence of chloride containing salts. Refinement is an essential chemical and physical process. Only through this kind of treatment undesired odorants, flavoring substances and possible traces of toxic compounds like pesticides, heavy metals or mycotoxins are eliminated. Increasing importance of the analysis of these contaminants due to their carcinogenicity. In March 2016, the European Food Safety Authority (EFSA) declared a reduced value for the tolerable daily uptake of 0.8 μg/kg body weight for 3-MCPD.
Author(s)
Tobias Uber, Marco Nestola, Hans-Joachim Huebschmann, and Andreas Bruchmann
Publication
Poster at the Separation Science Conference, Singapore Nov 2-3, 2017

2015
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Description
The only comprehensive reference on this popular and rapidly developing technique provides a detailed overview, ranging from fundamentals to applications, including a section on the evaluation of GC-MS analyses. As such, it covers all aspects, including the theory and principles, as well as a broad range of real-life examples taken from laboratories in environmental, food, pharmaceutical and clinical analysis. It also features a glossary of approximately 300 terms and a substance index that facilitates finding a specific application. The first two editions were very well received, making this handbook a must-have in all analytical laboratories using GC-MS.
Files
Handbook of GC-MS 3rd ed. Forword by Kaushik_Banerjee
Handbook of GC-MS 3rd ed. Introduction
Handbook of GC-MS 3rd ed. Preface
Handbook of GC-MS 3rd ed. Table of Contents
Author(s)
Hans-Joachim Hübschmann
Publication
3rd Edition 2015, Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 880 pages.
Handbook of GC-MS: Fundamentals and Applications
Abstract
Analysis of a multi-residue mixture of pesticides at these trace levels is extremely challenging due to the complex extracts resulting from sample preparation. The instrument method also involves a number of mass transitions making the method even more complex. In order to obtain maximum sensitivity within minimum possible run time the instrument should be capable of detecting a large number of compounds in a single chromatographic run while maintaining superior sensitivity. Thermo Scientific™ TSQ™ 8000 Evo triple quadrupole GC-MS/MS system is an excellent tool in this regard. Enhanced velocity optics (EVO) driving EvoCell collision cell technology provides high SRM transition speeds, precision, and sensitivity for even the most complex methods involving several pesticides within a short run time. Other advantages include timed-SRM and AutoSRM for SRM.
Author(s)
Shridhar Gawade, Aarti Karkhanis, Soma Dasgupta, Manish Kumar, Sunil T Kumar, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific, Mumbai, India, Application Note 10469
Abstract
Aloe vera (Aloe barbadensis Mill.) is a succulent plant species used in herbal medicine since the beginning of the first century A.D. Extracts from Aloe vera are widely used in the cosmetics and alternative medicine industries, having rejuvenating, healing, or soothing properties. Indian gooseberry (Amla, Phyllanthus emblica ) demonstrates in vitro antiviral, antimicrobial, and anticancer properties. All parts of the plant are used in various Ayurvedic/Unani medicines as herbal preparations, including the fruit, seed, leaves, root, bark and flowers. Aloe vera and Amla juices are also available in the market for direct consumption. However, there is increasing public concern about health risks from pesticide residues in food leading the strict regulation of maximum residue levels (MRL) and total dietary intake of pesticide residues in foodstuffs. International bodies, such as the Codex Alimentarius Commission and the European Union (EU), exert a major influence on food safety testing globally, with strict legislation in this area. According to Reg. 396/2005, Article 20 of the EU legislation no specific MRLs for juices are present which means that the MRL applied for juice is the corresponding MRL for the raw agricultural commodity.
Author(s)
Shridhar Gawade, Aarti Karkhanis, Soma Dasgupta, Sunil T Kumar, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific, Mumbai, India, Application Note 10464
Abstract
Gas chromatography coupled with mass spectrometry (GC-MS) is particularly well suited to the study of low molecular-weight metabolites that can be made amenable to gas chromatography by chemical derivatization. However, while metabolite profiling by GC-MS in full scan mode reports identities of metabolites and their normalized relative intensities, the ultimate requirement for a quantitative description of the metabolite pool is absolute concentration determination. When studying a plant such as rice, targeted metabolites need to be accurately quantified for use as tools for functional genomics or as biomarkers to discriminate between different traits of diverse rice quality.
Author(s)
Jeremy P. Matthews, Silvia Gemme, Hans-Joachim Huebschmann, Cindy Llorente, Rosario Jimenez, Nese Sreenivasulu
Publication
Thermo Fisher Scientific (2015) Application Note AN10419

2014
Abstract
“We called it, almost from the beginning, a “workhorse instrument.” It really, to this day, is that and more. With real advantages in scan speed, sensitivity, ease of use, a linear output, and workhorse capability it really caught on in a hurry.” Bob Finnigan 2001
Author(s)
Hans-Joachim Hübschmann
Publication
White Paper 10427, Thermo Fisher Scientific, Singapore
Abstract
Gel permeation chromatography (GPC) is based on the principle of molecular size separation and uses a porous column material. GPC is especially well suited to food extracts generated by the popular QuEChERS method1, where the matrix consists mostly of triglycerides (fat), pigments and other biopolymers, which can be separated from the desired small molecule pesticide compounds2,3. A powerful means of sample purification, gel purification has a wide range of applications internationally, such as the US EPA method 3640A4. China has adopted many standards, including GB/T 19650-20065, SN/T 0123-20106, SN/T 2149-20087, SN/T 2915-20118, pertaining to GPC as a purification method for the analysis of pesticide residues in various types of food.
Author(s)
Jinshui Che, Chongtian Yu, Lina Liang, and Hans-Joachim Huebschmann
Publication
Application Note AN10422, Thermo Fisher Scientific, Shanghai, China
Abstract
This is the first nationwide survey on nitrosamines in Korea by the sensitive electron impact ionization method. In the past, the main analytical stream of NDMA and their family compounds has been based on GC-CI-MS/MS. This proven method has been provided sensitive and reliable data. However, EI method can be applied with enough sensitivity due do the advanced ion focusing and timed selected reaction monitoring (timed SRM) technology. In this study, instrumental analysis for ionization method(EI,CI), sensitivity optimization etc. were tested. Sample preparation methods between commercialized SPE cartridges were validated. Finally, the optimized method was applied to the 76 treated samples from nationwide drinking water treatment plants.
Author(s)
Jaewon W. Choi, Y.D. Kim, J.M. Jung, and Hans-Joachim Huebschmann
Publication
ASMS conference poster #2402, Baltimore, MD, USA, 2014
Abstract
The analysis of alkylphenol compounds in food and environmental matrices, illustrating the productivity and high-quality results from the GC-MS/MS system with automated selected reaction monitoring (SRM) development. European regulations create high demand for analytical screening for these compounds at low levels in both water and food. Additionally, nonylphenol and nonylphenol ethoxylate have been part of a U.S. Environmental Protection Agency (EPA) action plan.
Author(s)
Inge De Dobbeleer, Joachim Gummersbach, Hans-Joachim Huebschmann
Publication
Application Note, Thermo Fisher Scientific, Dreieich, Germany
Abstract
Wir nannten es von Anfang an ein „Arbeitspferd“. Das ist es wirklich, bis zum heutigen Tag, und darüber hinaus viel mehr. Mit Vorzügen in Scan-Geschwindigkeit, Empfindlichkeit, einfacher Bedienung, einem linearen Signal, und seinem Leistunsvermögen setzte es sich schnell durch. (Bob Finnigan, 2001)
Author(s)
Hans-Joachim Hübschmann
Publication
GIT Labor Fachzeitschrift 3 (2014) 18-27

2013
Abstract
For the analysis of the 15 polycyclic aromatic hydrocarbons (PAH) classified as priority from the Scientific Committee on Food (SCF) and benzo[c]fluorene assessed to be relevant by the Joint FAO/WHO Experts Committee on Food Additives (JECFA) in food, a sensitive analytical method is necessary. Methods: A Fast-GC/HRMS method with a runtime of only 25 minutes using a TR-50ms column (10m x 0.1mm x 0.1μm) was developed. Results: 113 representative samples of commercial smoked German meat products were tested. The median of benzo[a]pyrene content was 0.03 mg/kg and therefore greater than a factor of 100 below the maximum level of 5 mg/kg. The determined LODs and LOQs were in the range of 0.003 – 0.01 mg/kg and 0.009 – 0.03 mg/kg, respectively.
Author(s)
Wolfgang Jira, Fredi Schwägele, Hans-Joachim Huebschmann, Heinz Mehlmann
Publication
Poster at the ISPAC, Internat. Symposium on Polycyclic Aromatic Compounds, Oregon State University, Corvallis, 08.-12.09.2013, Oregon.
https://docplayer.org/amp/18684524-Aus-der-arbeit-des-max-rubner-instituts-standort-kulmbach
Abstract
In the fully automated GC-EI-MS/MS, automated SRM mode provided 60% faster set up time and high sensitivity than the conventional GC-MS/MS method. The instrumental detection limit (IDL) of NDMA was 0.3 pg. IDL of other nitrosamines were 0.3-0.5 pg ranges. This indicated the low ng/L range LOQs for treated water samples with SPE sample concentration. The Auto SRM methodology is 60% faster than the conventional MRM set up. Points of SPE method : UCT cartridge, separated N2 with manual purging etc. In the real treated sample applications, NDEA was detected from all samples. Results of this study indicating the current EPA method 521 should be reassessed.
Author(s)
Y.D. Kim, J.W. Choi, J.M. Jung, and Hans-Joachim Huebschmann
Publication
APCE-KSFEA-APIA conference poster, Nov 2013, Korea

2012
Abstract
Purpose: To demonstrate the ability of the Thermo Scientific TSQ Quantum XLS Series Triple Quadrupole GC-MS/MS to analyze the 209 PCB congeners listed in EPA Method 1668A at low levels with high precision and can be used for screening of PCBs even in difficult matrices. Methods: Retention times were determined in full scan mode and then a timed-SRM method was developed. Standards were analyzed at concentrations as low as 20 fg on-column, and precision was determined at 100 – 300 fg. A variety of matrices were spiked at low levels. Results: Individual compound %RSDs ranged from 5 to 32 analyzing 9 replicate samples with an average for all 209 congeners of 13%. Low level matrix spikes demonstrated the selectivity of the instrument.
Author(s)
David Steiniger, Dirk Krumwiede, Eric Phillips, Hans-Joachim Huebschmann, Paul Silcock
Journal/Publication
Poster, PittCon 2012, Thermo Fisher Scientific, Austin, Texas USA.
Abstract
This poster describes the analysis of a large number of pesticide components from herbal and tea products using GC-MS/MS. These types of dried plant products usually deliver high matrix loaded extracts from the sample preparation, and hence, pose a particular analytical challenge to the chromatographic and mass spectrometer system for a sensitive quantitation. High analyte selectivity and long term robustness are key for the high productivity pesticide monitoring in a routine trace analysis lab.
Author(s)
Hans-Joachim Huebschmann, Joachim Gummersbach, Nicole Rueckert, Johann Kirchner, Elmar Häfner
Publication
Poster, Thermo Fisher Scientific, Dreieich, Germany.
Abstract
Over millions of years, organisms developed incredible ways to survive and interact with their often hostile environments. Different molecular levels of proteins and metabolites as well as their interactions, including gene expression, and underlying hierarchy of biochemistry and physiology can be summarized as the “genotype-phenotype relationship”.1 This link between genotype and phenotype is an issue of great interest and leads to the need for analyses at different molecular levels, the so called “omics” approaches: transcriptomics (gene expression), proteomics (protein translation) and metabolomics (metabolic network).
Author(s)
Fragner, L., W. Weckwerth, and H.-J. Huebschmann.
Publication
Thermo Fisher Scientific (2012) Application Note 51999, Austin TX, USA.
https://static.thermoscientific.com/images/D00847~.pdf
Abstract
Pesticides are widely used in agriculture to protect crops and to improve efficiency of production. Consequently, governments, food producers and food retailers have the duty to ensure that any residues occurring in foods for human consumption are at or below Statutory Maximum Residue Levels (MRLs). Regulation EC 396/2005 adopted in the European Union sets MRLs for more than 500 dif- ferent pesticides in over 300 different food commodities.
Author(s)
Inge de Dobbeleer, Joachim Gummersbach, Hans-Joachim Huebschmann, Anton Mayer
Publication
LCGC – The Application Notebook (2012) September 1, 9.
Thermo Fisher Scientific (2012) Application Note 52279, Dreieich, Germany

2011
Abstract
International regulations on maximum residue levels (MRLs) of pesticides in food cover hundreds of individual contaminants at the 10 ppb or below range. The analysis of citrus oil for pesticide contamination holds specific challenges. Pesticides that are used on citrus crops are concentrated along with the matrix in this oil. This matrix is known for its high boiling point components. The system of the Thermo Scientific TRACE GC Ultra and TSQ Quantum XLS GC–MS-MS allows for the analysis of more than 40 pesticides in citrus oil with minimal sample preparation.
Author(s)
Charles Lyle, Hans-Joachim Huebschmann, Eric Phillips
Publication
LCGC – The Application Notebook (2011) June 01, 2–5.
Abstract
The European Union Water Framework Directive seeks to lower detection and reporting limits for many contaminants (1). One class of these is organotins. Tributyltin compounds are considered the most hazardous, and several studies have shown the effect on shell malformation of oysters, imposex of marine snails and reduced resistance to infections (2,3). The method described uses the Thermo Scientific TSQ Quantum XLS triple quadrupole GC–MS–MS system to provide detection and quantification limits that go below regulatory requirements with the use of timed selected reaction monitoring (t- SRM).
Author(s)
Inge De Dobbeleer, Hans-Joachim Huebschmann, Anton Mayer, Joachim Gummersbach
Publication
LCGC – The Application Notebook (2011) August 02.
Abstract
The method described employs a triple quadrupole mass spectrometer equipped with hyperbolic quadrupole rods for increased selectivity to perform a trace level screening method for PCDD/Fs and PCBs and follows the well-established United States Environmental Protection Agency (US EPA) Method 1613A by using isotope dilution quantitation with 13C labelled internal standards.
Author(s)
Dirk Krumwiede, Hans-Joachim Huebschmann
Publication
LCGC North America 29 (2011) 2.

2010
Abstract
Because biomarker concentrations decrease with increasing thermal maturity, light oils contain only a low concentration of detectable biomarkers, and in consequence require instrumentation of highest selectivity and sensitivity. The information of source, thermal maturity, and secondary alteration processes are furthermore often revealed by only subtle variations in the isomeric distribution of such trace components. GC-MS/MS using the Thermo Scientific TSQ Quantum XLS is the premier analytical method for the sensitive characterization of “molecular fossil” biomarkers in crude oil.
Author(s)
Frank Theobald, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific (2010) Application Note 10261, Bremen, Germany
Abstract
Benzene and its alkyl derivatives toluene, ethylbenzene, and xylene (BTEX) have been classified by the World Health Organization (WHO) as a strong carcinogens causing cancer affecting human skin, lungs, and the nervous system. Quality control in the cigarette filter manufacturing process is a critical procedure for the tobacco industry. The reagents, accessories and raw filter material used in the production process may be a source of residual BTEX contamination, and hence require quality control. Therefore, the BTEX monitoring of cigarette filters in the tobacco industry has a significant impact on the choice and quality of filter materials. China is by far the largest tobacco producing country today, followed from a distance by Europe, North America and Latin America. In China, the directive YC/T 373-2010 for the control of propylene and C-fiber filter material requires the analysis of BTEX residue contaminations by gas chromatography-mass spectrometry (GC-MS).[3] The YC/T 373-2010 standard has high sensitivity requirements for the detection of BTEX. In this application note, we employ the method used in YC/T 373-2010 with the Thermo Scientific ISQ GC-MS for detection of BTEX compounds in propylene fiber cigarette filters.
Author(s)
Xuebin Zhang, Chongtian Yu, Lina Liang, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific, Shanghai, China, Application Note 10399
Abstract
This method can be applied to fish and other fatty seafood samples to detect simultaneously the presence of aliphatic hydrocarbons and PAH contamination from crude oil found in the Gulf of Mexico. From the profile using GC-MS/MS, the method can be used to characterize the source of contamination. The method gives a quantitative indication as to whether levels of PAHs exceed safety limits for human consumption.
Author(s)
Klaus Mittendorf, Laszlo Hollosi, Ebru Ates, Katerina Bousova, Eric Phillips, Hans-Joachim Huebschmann, James Chang
Publication
Thermo Fisher Scientific, Food Safety Response Center (2010) Method 51991.
Abstract
Pesticides are widely used in agriculture to protect crops and to improve efficiency of production. Consequently, governments, food producers and food retailers have a duty to ensure that any residues occurring in foods for human consumption are at or below statutory maximum residue Ieveis (MRLs). Regulation EC 396/2005 adopted in the European Union sets MRLs for more than 500 different pesticides in over 300 different food commodities.1 Many of these MRLs are set at adefault value of 0.01 mg/kg, the typicallimit of determination of routine analytical methods. Thus, there is a requirement for residue laboratories to test a wide array of foods for a large number of pesticides at concentrations at or below 0.01 mg/kg , with low costs and fast turnaround. This is most often achieved using multiresidue methods based on the use of a combination of LC-MS- MS and GC-MS techniques to determine pesticide residues in a single generic solvent extract of the sample. One such example is the quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure, which is based on acetonitrile extraction and dispersive solid-phase extraction. 2 Because acetonitrile is readily compatible with LC- MS- MS and allows analysis of several hundred pesticides this approach has gained in popularity. Many of the less polar semi-volatile pesticides not amenable to LC-MS can be analysed using GC- MS. Unfortunately, the analysis of acetonitrile QuEChERS extracts by GC-MS is more problematic, primarily due to degradation of the GC-column phase by the polar solvent, vapour overload of the insert Iiner due to the high thermal expansion coefficient, contamination of the system by co-extractives and low crop concentration in the final extracts.
Author(s)
Hetmanski, M. T., Fussell, R. J., Godula, M., Huebschmann, H.J.
Publication
The Applications Book, July/August 2010, 14-15.
Abstract
Pesticides are widely used in agriculture to protect crops and to improve efficiency of production. Consequently, governments, food producers and food retailers have a duty to ensure that any residues occurring in foods for human consumption are at or below Statutory Maximum Residue Levels (MRLs). Regulation EC 396/2005 adopted in the European Union sets MRLs for more than 500 different pesticides in over 300 different food commodities. 1 Many of these MRLs are set at a default value of 0.01 mg/kg, the typical limit of determination of routine analytical methods. Thus, there is a requirement for residue laboratories to test a wide array of foods for a large number of pesticides at concentrations at or below 0.01 mg/kg, with low costs and fast turnaround times (often< 48 hours). This is most often achieved using multi-residue methods based on the use of a combination of LC/MS/MS and GC/MS techniques to …
Author(s)
Michael T. Hetmanski, Richard Fussel, Michal Godula, Hans-Joachim Hübschmann
Publication
Thermo Fisher Scientific (2010) Application Note 51880, Bremen, Germany.

2009
Abstract
The physico-chemical diversity of biological small molecules makes a metabolomic analysis very difficult. Therefore, different analytical strategies are necessary and are ideally combined with each other. Analyses focusing on a group of metabolites or watching as many metabolites as possible at specified environmental or developmental stages is called metabolite profiling. On the other hand metabolite target analyses are restricted to specific metabolites of interest, which can be selectively monitored and quantified. There is a discrepancy of detectable peaks in a typical metabolomics sample and the number of assignable chemical identifications due to a restricted availability of non-complete reference libraries and technical problems such as ultracomplex coelution of compounds and non-optimal mass spectral deconvolution in gas chromatography-mass spectrometry. Therefore, we propose an integrative approach combining advantages of targeted analysis using multiple reaction monitoring (MRM) and full scan measurements to enhance the selectivity of the analysis, increase the number of identifiable and selectively quantifiable chemical structures and allow for absolute quantification strategies.
Author(s)
Hans-Joachim Huebschmann, Lena Fragner, Wolfram Weckwerth, and Dwain Cardona
Publication
Poster, Thermo Fisher Scientific (2009) Austin TX, USA
Abstract
Die bisherigen Methoden zur Quantifizierung von Tetrahydrocannabinol-Carbonsäure in Urin arbeiten in der Regel nur bei relativ hohen Konzentrationen genau. Für Analysen im unteren Picogramm-oder gar Femtogrammbereich sind sie daher in der Regel ungeeignet. Wir stellen hier eine Methode vor, die durch hohe Wiederfindungsraten und eine hochsensitive Detektion charakterisiert ist und sich zur sicheren Identifizierung und Quantifizierung der THC-Carbonsäure in Harnproben auch von ProVolumeen mit geringer und unregelmäßiger Cannabis-Exposition eignet.
Author(s)
Hans-Ulrich Melchert, Hans-Joachim Hübschmann, Ellen Pabel
Publication
LaBo, Januar 2009 (German), 8-12. Also online at LaBo 01.01.2009:
https://www.labo.de/analyseninstrumente/instrumentelle-analytik—fachbeitrag—analytik-der–thc-carbonsaeure.htm
Abstract
International regulations on the maximum residue levels of pesticides in food (MRLs) cover many hundreds of individual components at very low maximum residue limits in the range of only 10 ppb or even below [1]. More than 500 regulated pesticides can be analyzed by gas chromatography/mass spectrometry (GC/MS) while the group of highly polar pesticides is covered by liquid chromatography/mass spectrometry (LC/MS) methods [2]. GC/MS analysis of that many pesticide compounds at the MRL becomes an increasing challenge for food safety and governmental control strategies. This application describes the analytical methodology for a fast multiresidue pesticide determination using the unique highly selected reaction monitoring capabilities (H-SRM) and timed SRM data acquisition with the Thermo Scientific TSQ Quantum™ GC triple quadrupole mass spectrometer [3]. More than 1000 compounds can be screened in the multiple reaction monitoring method (MRM) in only one run for quantitation and confirmation of positive results.
Author(s)
Hans-Joachim Huebschmann; Weiguo Zhang, Lin Lu; Joachim Gummersbach
Publication
Poster at the 6th GCxGC Symposium, Portland OR, USA. Application Note AN10263 (2008) Thermo Fisher Scientific, Shanghai, China, and Bremen, Germany
https://cdn.ymaws.com/www.casss.org/resource/resmgr/imported/ISCCE2009_FINALProgram_050809.pdf
Abstract
It is an excellent move that you look into this book! Analytical chemists want to be efficient and rapid: we are interested in a given task and the results should be available the next morning. This suggests taking the simplest route: “inject and see”, there is no time to fiddle about technology! The vendor of the possibly ex- pensive instrumentation might have highlighted the simplicity ofhis apparatus. This is a fundamental error. Efficient analysis presupposes a significant amount of time being devoted to understanding the method and the instrumentation. Not doing this in the beginning all too often exacts a high price at a later stage, e.g. in terms of a laborious and awkward method, endless troubleshooting and poor results. Knowledge of the technology is a prerequisite to make the best choices for a straight and simple method – from sample preparation to injection, chromatographic resolution and de- tection. If we are honest, we know that a staggering amount of our time is lost to trouble- shooting, and unless we have a deep insight into the technology, this troubleshooting is likely to be frustrating and ineffective (problems tend to recur). Hence investing time into understanding the technology is a wise investment for rapid (and reliable) analysis. …. It is great that an old hand in the field like Hans-Joachim Hübschmann took his time to bring the present knowledge into such a concise and readable form. Continue reading!
Author(s)
Hans-Joachim Hübschmann
Publication
2nd Completely revised and updated Ed., Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, 719 pp.

2008
Abstract
For the analysis of the 15 polycyclic aromatic hydrocarbons (PAH) classified as priority from the Scientific Committee on Food (SCF) and benzo[c]fluorene (BcL) assessed to be relevant by the Joint FAO/WHO Experts Committee on Food Additives (JECFA) in food, a sensitive analytical method is necessary. In the past, many methods were established for only the analysis of the 16 priority PAH recommended by the US Environmental Protection Agency (16 EPA-PAH) but not for the 15 SCF-PAH and BcL. Therefore, at the Max-Rubner-Institut, Federal Research Institute of Nutrition and Food in Kulmbach, Germany, an analytical method with a runtime of 72 min was developed. To shorten this runtime without a loss of separation, a Fast-GC/high reso- lution MS (HRMS) method with a runtime of only 25 min using a TR-50ms column (10 m60.1 mm60.1 lm) was created. The repeatability (n = 3) of spiked PAH concen- trations in test-matrix tea ranged from 0.1 to 11%. The analytical parameters LOD (0.01–0.02 lg/kg) and LOQ (0.03–0.06 lg/kg) also in the test-matrix tea were deter- mined. A good linearity for all PAH (R2 A0.99) and averaged recoveries from 75 to 117% in the concentration range of1–20 lg/kg were achieved.
Author(s)
Katja Ziegenhals, Hans-Joachim Huebschmann, Karl Speer, and Wolfgang Jira
Publication
J. Sep. Sci. (2008). 1779–1786.
https://doi.org/10.1002/jssc.200700641
Abstract
International regulations on the maximum residue levels of pesticides in food (MRLs) cover hundreds of individual components at very low maximum residue limits – in the range of 10 ppb or lower. Currently, more than 300 regulated pesticides can be analyzed by gas chromatography/mass spectrometry (GC/MS) while a large group of highly polar pesticides is covered by liquid chromatography/mass spectrometry (LC/MS) methods. GC/MS analysis of that many pesticides at the MRL becomes an increasing challenge for quality and governmental control strategies. This application note provides the analytical methodology for a fast multi-residue pesticide determination using the unique capabilities of the Thermo Scientific TSQ Quantum™ GC triple quadrupole mass spectrometer for quantitation and confirmation of positive results. A particular challenge in the detection and quantification of a large number of pesticides in one run derives from the complex elution situation. Because many compounds partially or completely coelute, a high speed analyzer is required to generate a sufficient number of data points. This ensures reliable integration of overlapping chromatographic peaks.
Author(s)
Weiguo Zhang, Lin Lu, Hans-Joachim Huebschmann
Publication
LCGC Germany, 2008, May/June, 22–26. Thermo Fisher Scientific, Application Note AN10263

2007
Abstract
The analysis of toxaphenes still is challenging, not limited to the almost impossible chromatographic separation of the vast amount of isomers, the injection technique as well as the ionization performance have a great influence over reproducibility, linearity and sensitivity. High resolution GC/MS offers the potential for a sensitive analysis providing the selectivity to overcome limiting interferences with matrix components as well as possible coelutions with other xenobiotica. Toxaphenes are included in the Annex A of the Stockholm Convention to protect human health and the environment from persistent organic pollutants (POPs). The international community has called for urgent global actions to reduce and eliminate releases of these listed chemicals including toxaphenes. Toxaphene is a complex mixture of polychlorinated camphenes (polychlorinated bornanes) that was first introduced in 1945 as broad band insecticide. The vast number and complexity of isomers results from the simple production process from the UV catalysed reaction of chlorine with camphene providing a product with a chlorine content of about 67 to 69%. The lipophilic, persistent and volatile nature of toxaphene has contributed to its global dispersion throughout freshwater and marine environments. Therefore, increased attention has been focused on toxaphene, both in the analytic and toxi- cologic fields. Toxaphene is believed to present a potential carcinogenic risk to humans.
Author(s)
Frank Theobald, and Hans-Joachim Huebschmann
Publication
Poster, Thermo Fisher Scientific (2007) Bremen, Germany
Abstract
Gas chromatographic (GC) methods require a specific chromatographic resolution for a given set of compounds in order to resolve analyte peaks from interferences, other analytes or homologues present in the same sample solution. This requirement is often a limitation when trying to shorten down GC run times in order to save valuable analysis time. A good example is the analysis of polychlorinated dioxins and furans (PCDD/Fs) by GC/mass spectrometry (GC/MS), e.g. in accordance to methods EPA 1613, or EN 1948. In order to achieve the requested GC resolution and other method requirements, typical total GC runtimes of up to 45 minutes, with the first peaks of interest elution after about 20 minutes. In other words, during the first 20 minutes no data acquisition takes place on the MS detector, wasting valuable instrument time.
Author(s)
Jens Griep-Raming, Stefan Ahlbrand, Dirk Krumwiede, and Hans-Joachim Huebschmann
Publication
Organohalogen Comp. 69 (2007) 1197–98

2006
Abstract
Target compound analysis e.g. for polychlorinated dioxins, furans (PCDD/F), pesticides, persistent organic pollutants (POP) or pharmaceutical residues are typically performed by monitoring the compound specific ions at the expected retention time for each analyte. The DFS High Resolution GC/MS benefits from a unique technical feature referred to as the lock-mass technique for performing multiple ion detection (MID) analyses. The lock mass technique provides ease of use, combined with a maximum quantitative precision and certainty in analyte confirmation. This technical note describes the DFS mode of MID operation using a lock-plus-cali mass technique in detail and gives valuable hints for the setup of rugged routine methods.
Author(s)
Hans-Joachim Huebschmann, Jens Griep-Raming
Publication
Technical Note, Thermo Fisher Scientific, Bremen, Germany

2005
Abstract
多氯联苯包括 209 种不同的单体 (同系物), 对健康有不同的影响. 虽然美国早在 1977 年就禁止生产 PCBs, 用 PCBs 制造的产品却仍然在使用. 由于多氯联苯在环境中降解缓慢, 所以它们可以被气流带到了地球的各个角落. PCBs 已经污染了地球上所有动物及人类的身体. 《 关于持久性有机污染物的斯德哥尔摩公约》 将 PCBs 列为世界上已知对人体和环境有害的十二种最危险的化合物之一. 尽管体内二恶英水平在缓慢稳定的下降, 反映出多种防止扩散的努力总的来说取得了一定效果, 然而 PCBs 污染水平在全球来讲预计不会发生变化 (2007 东京二恶英研讨会). 对二恶英水平的监测作为斯德哥尔摩公约的工作项目还将继续多年, 会涉及大量样品的采集, 尤其是对于危险的类二恶英 PCBs (dl-PCB) 来说. 值得一提的是共面 dl-PCB, 即非间位取代的 PCB, 由于具有与 2, 3, 7, 8-TCDD 类似的毒性, 成为食品安全控制的焦点. dl-PCBs 也对样品毒性当量 (TEQ) 值有显著贡献.
Author(s)
Dirk Krumwiede, Hans-Joachim Huebschmann
Publication
Thermo Fisher Scientific (2005) Application Note CM0105, Bremen, Germany

2004
Abstract
With the introduction of compound specific isotope analysis by isotope ratio monitoring GC/MS (irm-GC/MS) the immediate demand for similar applications using HPLC was created. In irm-GC/MS the carrier is helium which does not interfere with the essential combustion step prior to isotope ratio mass spectrometry (IRMS). In opposite the LC mobile phase has inhibited a similar direct conversion up to now. All earlier irm-LC/MS approaches were based on the removal of the liquid phase prior to combustion risking fractionation of the isotope ratios of the eluted compounds. To avoid such restrictions we developed a new continuous flow concept for the coupling of an HPLC system to the isotope ratio MS for d13C isotope ratio analysis. The differentiating idea of the new concept is to leave the compounds in the effluent and to combust them still in aqueous phase. Therefore this strategy is based on water and inorganic buffers as mobile phase. The resulting CO2 compound peaks are then separated from the effluent and analysed with the isotope ratio MS.
Author(s)
Dieter Juchelka, Hans-Joachim Huebschmann, Andreas Hilkert, Michael Krummen, Reinhold Pesch
Publication
Poster at the 33. Lebensmittelchemiker Tag in Bonn, Germany_Poster PA56, Thermo Electron Corporation, Bremen, Germany

2001
Author(s)
Hans-Joachim Huebschmann, Nigel Baldwin
Publication
Poster, Deutscher Lebensmittelchemikertag 2001 in Braunschweig, Germany, OmegaTech GmbH, Wendelsheim, Germany
Cite as:
Huebschmann, H.-J., & Baldwin, N. (2002). Entwicklung und Herstellung eines DHA-reichen Fermentationsöles aus Algen. Lebensmittelchemie, 56, 32
Author(s)
Gerhard Kohn, Ruben Abril, Wulf Banzhaf, Hans-Joachim Hübschmann
Publication
Poster, Deutscher Lebensmittelchemikertag 2001 in Braunschweig, OmegaTech GmbH, Wendelsheim, Germany
Cite as:
Kohn, G., Abril, R., Banzhaf, W., & Huebschmann, H.-J. (2002). Neuartige Phospholipide bioaktiver Fettsäuren und Wege zu deren Herstellung. Lebensmittelchemie, 56, 33
Author(s)
Hans-Joachim Hübschmann
Publication
Weinheim: Wiley-VCH 2001, 592 pages, revised and supplemented English translation.

1997
Author(s)
Dirk Kohlmüller, Hans Joachim Hübschmann
Publication
in: O. Kaiser, R. E. Kaiser (Eds.): Chromatography – Celebrating Michael Tswett’s 125th Birthday, Düsseldorf: Incom Bureau 1997, 167 – 175
Abstract
This article describes the development and application of the target compound analysis for phenoxyalkyl carbonic acid herbicides. The sample preparation takes advantage of an automated solid phase extraction System. The extracts are derivatised using diazomethane as reagent. The determination of the herbicides is tarried out with GC/MS in full scan mode. The full spectrum information allows the positive identification of the components prior to quantification with internal standard method. The automated method of sample preparation and compound determination is routinely used for high sample loads today.
Author(s)
Franz Kriegsmann, Hans Joachim Hübschmann
Publication
GIT Labor Fachz. 1 (1997), Sonderdruck
Author(s)
Hans Joachim Hübschmann
Publication
in: L. Matter (Ed.), Food and Environmental Analysis by Capillary Gas Chromatography, Heidelberg: Hüthig 1997, 119 – 171
Author(s)
Hans Joachim Hübschmann
Publication
in: F. Pragst (Hrsg.): GTFCh-Symposium – Moderne Meßverfahren im Rahmen der Toxikologisch-Forensischen Begutachtung, Mosbach 18. – 19. April 1997, Verlag Helm: Heppenheim

1996
Author(s)
Hans Joachim Hübschmann
Publication
Weinheim: VCH Verlagsgesellschaft, 1996, 586 pages, 1st edition, Germany

1995
Author(s)
Hans Joachim Hübschmann
Publication
LABO 7/8 (1995) 42-49
Abstract
Prinzipiell können in der Massenspektroskopie sowohl positive als auch negative Ionen erzeugt und analysiert werden. Die Elektronenstoß-lonisierung (electron impact, EI) als das Standardverfahren zur Ionenerzeugung liefert überwiegend positive Ionen. Die EI-Massenspektren haben ihre Bedeutung bei der Identifizierung und Bestätigung von Substanzen durch Bibliotheksvergleich. Die Ionisierungsenergie von 70 eV führt zu charakte- ristischen Fragmentierungen und Umlagerungsreaktionen der Moleküle, die eine wertvolle Information zur Strukturaufklärung darstellen. Durch die EI-Ionisierung ist die Massenspektroskopie zu einem universellen und massenspezifischen Detektionsverfahren in der GC/MS geworden.
Author(s)
Hans Joachim Hübschmann
Publication
GIT Fachzeitschrift Labor, 39 (1995) 434-438

1994
Author(s)
Hans Joachim Hübschmann
Publication
in: L. Matter (Ed.): Lebensmittel- und Umweltanalytik mit der Kapillar-GC Weinheim: VCH Verlagsgesellschaft 1994, 117 – 172
Abstract
A new method of mass spectrometric trace analysis using ion trap detectors based on positive chemical ionization with water as reactant is presented. The technique has advantages over the methods commonly used with regard to selectivity and sensitivity and facilitates detection of labile organic compounds. The specific increase in analytical response with water Cl for the analysis of nitrated aromatic substances is described.
Author(s)
Hans Joachim Hübschmann, Jörg Niebel, Andreas Landrock, H. Richter, H. Merten
Publication
Lecture on the Sixteenth International Symposium on Capillary Chromatography 1994, Riva, Italy

1992
Abstract
Die weite Verbreitung von Massenspektrometern als Detektoren in der Gaschromatographie hat die Diskussion über Bibliotheks- suchverfahren neu aufleben lassen. Insbesondere seit Einführung der Ion-Trap-Massenspektrometer im Jahre 1985 ist auch die ldentifizierung von Substanzen im Spurenbereich (pg-Bereich) einem breiten Anwenderkreis möglich geworden [I]. Be- dingt durch die unterschiedliche Softwareausstattung der Bench- top-GCMS-Systeme verschiedener Hersteller, haben sich, von der Anzahl der Installationen betrachtet, zwei Suchverfahren interna- tional durchgesetzt: INCOS und PBM, deren Leistungen und grundlegende Algorhythmen deshalb Gegenstand dieses Beitrages sind.
Author(s)
Hans Joachim Hübschmann
Publication
LABO Analytica (1992) 102.
Author(s)
Hans Joachim Hübschmann
Publication
Part 1, LaborPraxis 10 (1990) 808
Part 2, LaborPraxis 12 (1990) 1014

1990
Author(s)
Hans Joachim Hübschmann
Publication
Finnigan MAT (1990) Application Report No. 75
Abstract
Im ersten Teil des Beitrages wird die Funktion des Ion-Trap-Analysators erläutert und auf die Umsetzungsreaktionen bei der chemischen Ionisierung eingegangen. Ausführlich dargestellt werden die unterschiedlichen Betriebsweisen im EI- und Cl- Modus sowie die aus dem Einsatz der Cl-Ionisierung resultierenden Möglichkeiten für die massenspektrometrische Rückstandsanalytik auf Pflanzenschutzmittel.
Author(s)
Hans Joachim Hübschmann
Publication
LaborPraxis (1990) Oktober, 808-812, and 1014-1017
Author(s)
Hans Joachim Hübschmann
Publication
Finnigan MAT (1990) Application Report No. 75
Author(s)
Hans Joachim Hübschmann
Publication
INCOM Sonderdruck (1990) 475

1989
Author(s)
Hans Joachim Hübschmann
Publication
INCOM Sonderdruck (1989) 485

1988
Author(s)
Hans Joachim Hübschmann
Publication
Finnigan MAT (1988) Application Report No. 68
Author(s)
Hans Joachim Hübschmann
Publication
Finnigan MAT (1988) Application Report No. 67
Author(s)
Hans Joachim Hübschmann
Publication
Finnigan MAT (1988) Application Report No. 63

1987
Abstract
Nachfolgend soll das automatische Bestimmungsverfahren der Thermodesorption mit massenselektiver Detektion (Ion Trap Detektor ITD700) beschrieben werden. Dieses Verfahren bewährt sich besonder bei der Handhabung von komplizierten Matrices, wie sie z. B. bei Lösemitteln vorliegen. Sich überlagernde Komponenten können hier zweifelsfrei identifiziert und störungsfrei quantifiziert werden. Dies wird an zwei Beispielen, der Bestimmung von Lösemittelkomponenten und Narkosegasen ausgeführt.
Author(s)
Michael Tschickard, Hans Joachim Hübschmann
Publication
Finnigan MAT, Application Note No.67 (1987) Bremen, Germany
Author(s)
Hans Joachim Hübschmann
Publication
In: 2. Praktina, Europäisches Symposium fiir praktische instrumentelle Analytik, Krefeld, Hoppenstedt (1987) 77
Abstract
Neben der Standardbetriebsweise durch ElektronenstoB-Ionisierung (EI) steht für den Ion Trap Detektor ITD 800 zur Absicherung von Strukturidentifizierungen und zur Durchführung von quantitativen Analysen hoher Selektivität jetzt auch die chemische Ionisierung (Cl) zur Verfügung. Aufgrund des einzigartigen Analysators sind zum Betrieb mit chemischer Ionisierung keinerlei Umbauten erforderlich. Die chemische Ionisierung ist vollständig von der Software kontrolliert und erlaubt dem Benutzer erstmals die Vorwahl der Reaktionszeiten. Der Einlaß des Reaktantgases erfolgt regelbar über ein Nadelventil direkt in die Meßzelle. Als Reaktantgas können alle herkömmlichen Cl-Gase wie Methan, iso-Butan, Ammoniak und sogar Wasser eingesetzt werden. Der Arbeitsbereich liegt bei Partialdrücken von ca. 10-5 Torr. Bei der chemischen Ionisierung wird das in den Analysator geleitete Reaktantgas durch einen kurzen Elektronen-Impuls ionisiert. Die hierbei gebildeten Reaktantionen werden gespeichert und reagieren anschließend mit den neutralen Probemoleküien, die durch Elution von der GC-Säule in den Analysator gelangen. Die gebildeten Substanz-Ionen werden gespeichert. ln dieser Phase ist der Elektronen-Impuls bereits abgeschaltet und die Ionenerzeugung erfolgt durch eine rein chemische Ionisierung.
Author(s)
Hans Joachim Hübschmann
Publication
Poster at the Symposium über klinisch toxikologische Analytik bei akuten Vergiftungen und Drogenmißbrauch, Salzburg 1987, Austria
Abstract
Heute ist in der organisch-chemischen Analytik der Nachweis und die Bestimmung einer wachsenden Anzahl von Stoffen in immer geringeren Konzentrationen erforderlich. In der Regel liegen die Konzentrationen der Analyten trotz aufwendiger Aufarbeitungsverfahren deutlich unterhalb einer begleitenden Matrix, dem chemischen Rauschen. Die Möglichkeiten der Anreicherung und des Cleanup weisen für diese Aufgabenstellungen bei Realproben Grenzen auf. Der bedeutende analytische Gewinn beim Einsatz von GC/MS-Systemen gegenüber einem Nachweis mit klassischen Detektoren wie ECD oder FID liegt in der Spezifität. Abgeleitet von der Zusammensetzung und Struktur der Analyten kann der Substanznachweis in der GC/MS mit zielgerichteter Selektivität für bestimmte Substanzklassen erfolgen, ohne daß die Universalität des „Detektors “eingeschränkt wird.

Today, organic-chemical analysis requires the detection and determination of a growing number of substances in ever lower concentrations. As a rule, the concentrations of the analytes are well below a elaborate purification methods, the concentrations of the analytes are clearly below an accompanying matrix, the chemical noise. The possibilities of enrichment and cleanup have limits for these tasks with real samples. The significant analytical gain in the use of GC/MS systems compared to a detection with classical detectors such as ECD or FID lies in the specificity. Based on the composition and structure of the analytes, substance detection in GC/MS can be carried out with targeted selectivity for specific substance classes without limiting the universality of the detector“ is restricted.
Author(s)
Hans Joachim Hübschmann
Publication
GTFCh Media, 56-69. (German)
Abstract
Vor einem Jahr ist in der Bundesrepublik Deutschland die Verordnung über gefährliche Stoffe in Kraft getreten. Sie dient dem Schutz des Arbeitnehmers überall dort, wo gesundheitsgefährdende Stoffe eingesetzt werden. Ist das Auftreten gefährlicher Stoffe in der Luft am Arbeitsplatz nicht sicher auszuschließen, so muß geprüft werden, ob die maximalen Arbeitsplatzkonzentration (MAK-Werte) überschritten sind. Auch die Gesamtwirkung verschiedener gefährlicher Stoffe ist zu beurteilen.
Author(s)
Hans Joachim Hübschmann
Publication
Chemische Rundschau 39 (1987)

1986
Abstract
Routinemäßig werden die Proben, nach entsprechender Aufarbeitung, meist mittels HPLC/Fluoreszenzdetektion oder GC/FID analysiert. Bei diesen Verfahren können sich besonders bei komplexen Matrizes Schwierigkeiten bei der Identifizierung und Quantifizierung der einzelnen Substanzen ergeben. Zur Absicherung solcher Ergebnisse ist eine GC/MS Analyse vorteilhaft. Bei Anwendung der Single Ion Technik wird meist auch eine höhere Empfindlichkeit erzielt. Durch die Vielfalt der bei einer GC/NS Analyse anfallenden Daten bieten sich eine Reihe von Möglichkeiten zur Auswertung der Chromatogramme an. Dabei kann vor allem durch die rechnerische Rekonstruktion der Ionenchromatogramme der für das Massenspektrum der gesuchten Verbindungen charakteristischen Ionen die Quantifizierung vereinfacht und verbessert werden.
Author(s)
Inge Trummer, P. Mohr, Andreas Wolf, Gerhard Miksche, Hans-Joachim Hübschmann and Hermann Katzlinger
Publication
Poster at the Deutsch-Österreichisches Chemikertreffen, Innsbruck, 12.-14. Mai 1986
Abstract
The Finnigan MAT ION TRAP DETECTOR (ITD) is a sophisticated GC detector, which uses a new mass separation technology. It allows the chemist to separate analytical samples by mass as well as by retention time. Positive identification of the eluting compounds is achieved by supplementing GC retention time data with the mass spectra obtained with the ITD. This identification is further facilitated by the extensive library search capabilities of the system. The ITD is interfaced to any capillary GC by means of a flexible transfer line. It will accept the effluent from both narrow-bore (0.25 mm ID) and wide-bore (0.32 mm ID) fused silica columns. The transfer line includes an open split interface, which allows direct comparison of retention times produced with a conventional GC detector. Set-up of the ITD as well as data acquisition and processing are handled by an IBM Personal Computer XT. All acquired data and spectrum libraries (e.g. NBS library with more than 38.000 spectra) are stored on a 10 Mbyte hard disk. The application software programs are accessed via one letter commands. Those programs requiring additional input guide the user to respond with on-screen prompts.
Author(s)
Hans-Joachim Hübschmann, Ralf Schubert
Publication
Progress in Essential Oil Research (1986) 643
Abstract
GC-MS Analyse von Ethylcarbamat in Obstbränden
Author(s)
Hans-Joachim Hübschmann, Lothar Matter
Publication
Chemische Rundschau 29. August (1986) 14

1985
Abstract
ln den letzten Monaten wurde in vielen Weinen Diethylenglykol nachgewiesen. Die Bestimmung erfolgt meist gaschromategra- phisch auf Carbowax-Phasen und mit dem FID als Standard- Detektor. Die Identifizierung wird ausschließlich über die Retentionszeit erreicht. Hierbei wird die sichere Zuordnung des Diethy- lenglykoi-Peaks besonders im unteren ppm-Bereich erschwert durch die Fülle der Weininhaltsstoffe. Da zur Bewältigung des außerordentlich hohen Analysenanfalls der Wein in der Regel ohne Aufarbeitung direkt injiziert wird, ergibt sich, hauptsächlich durch hohen Zuckergehalt bedingt, eine starke Belastung des Injektors und der Trennsäule. ln der Folge können Retentionszeitverschiebungen des Diethylenglycols auftreten und damit zu Fehlinterpretationen führen. Die Quantifizierung des Diethylenglykols kann bei Verwendungen des FID durch koeluierende Inhaltsstoffe gestört werden. Es ist hierbei zu berücksichtigen, daß sowohl die Qualität als auch die Quantität der Weininhaltsstoffe denen eines Naturproduktes eigenen Schwankungen unterliegen. Unter den angegebenen Bedingungen eluiert Diethylenglycol (DEG) bei einer Retentionszeit von 5:18 min. Die Quantifizierung erfolgt durch Integration des Intensitätssignals auf den für DEG charakteristischen Massen m/z 75 bis m/z 76 auf Basis des zugehörigen Massenfragmentegramms.
Author(s)
Hans-Joachim Hübschmann, Hermann Katzlinger
Journal/Publication
Lebensmittel- und Biotechnologie 4 (1985) 148-149
Abstract
Die Ringelektrode wird mit einer Gleichspannung und fiberlagertem Hochfrequenzfeld so betrieben, dab eine Speicherung von Ionen fiber den gesamten ausgew/ihlten Massenbereich erm6glicht wird. Nach der Ionisierungs-und Speicherphase wird das angelegte Feld ver/indert, so dab sukzessive definierte m/z-Werte instabil werden und den Speicherring in axialer Richtung verlassen. Die Ionen treten durch die Perforation der unteren Elektrodenkappe und treffen auf den Detektor auf. Das Detektorsignal korrespondiert als Funktion der Zeit mit dem Spektrum der zuvor gespeicherten Ionen. Das ITD kann fiber eine Transferline an jeden Gas-Chromatographen angeschlossen werden. Der Anschlug von Capillars/iulen erfolgt fiber eine offene Kopplung, die eine Beibehaltung
Author(s)
Hans Joachim Hübschmann
Publication
Fresenius‘ Journal/Publication für analytische Chemie 320, 7 (1985) 693-694. Cite this article: Hübschmann, H.J. Der Ion-Trap-Detektor: Technologie und Anwendungen. Z. Anal. Chem. 320, 693–694 (1985).
https://doi.org/10.1007/BF00497162
(Use of Negative Chemical Ionisation Mass Spectrometry with Selective Reagent Gas Mixtures for the Detection of Diethylstilbestrol)
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Hans Joachim Hübschmann – Thesis 1985
Author(s)
Hans-Joachim Hübschmann
Publication
Thesis 1985
Institution
Technical University, Institution for Food Chemistry, Berlin (Germany)

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