Join us at Pittcon
February 27 - March 1, 2018 in Orlando, FL
Stop by the MilliporeSigma booth #2618 to learn about our complete range of high-quality products for accurate & remarkable results in a variety of analytical applications, including:
- Chromatography
- Filtration
- Laboratory Chemicals
- Water Purification
- Certified Reference Materials & Standards
- Sample Collection & Preparation
- Solvents & Reagents
- Titration & Spectroscopy
… from our famous brands Supelco, Sigma-Aldrich, Milli-Q and Millipore
Venue: Orange County Convention Center – West
Pittcon Presentations
Poster Presentations | Oral Presentations
Poster Presentations
| Poster Presentation | Title | Author | Co- Authors |
| Title | Approaches for the Analysis of Pesticide Residues in Cannabis | Katherine Stenerson | Jennifer Claus |
| Date: | Tuesday, February 27th | Gary Oden | |
| Abstract Number | 1030-61 | Michael Halpenny | |
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | Afternoon | ||
| Abstract | Consumption of cannabis and/or cannabis based products is currently legal in some form in 28 US states plus the District of Columbia. Testing of the plant materials and products is required by many of these states; however the specific test methods and target compound lists are not mandated in all cases. In October of 2016, the state of Oregon took a major step forward by requiring that all labs testing cannabis be accredited by the Oregon Environmental Laboratory Accreditation Program (ORLEP) and licensed by the Oregon Liquor Control Commission (OLCC). Consequently, Oregon Administrative Rules (OAR) list specific contaminants to be tested in marijuana samples, along with action levels. The pesticides on this list include carbamate, organophosphorus, macrocylic lactone, neonicotinoid, pyrethroid, and triazole fungicides as well as others. A common approach for determination of these residues is the use of QuEChERS extraction followed by both LC/MS/MS and GC/MS/MS analysis. The extracts produced by this method present several challenges to chromatographic analysis; such as background from co-extracted matrix components such as chlorophyll and cannabinoids, and peak shape issues in LC. In this presentation, we will show a specific approach to address these issues in the analysis of cannabis samples spiked with pesticides included on the OAR list. Aspects will include column and mobile phase selection for LC/MS/MS, and the use a new cleanup sorbent blend for QuEChERS that offers several advantages over PSA/C18/GCB. |
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| Poster Presentation | Title | Author | Co- Authors |
| Title | LC-MS Analysis of Chiral Compounds under Reversed Phase Conditions Using Macrocyclic Glycopeptides Stationary Phase | Michael Ye | Craig Aurand |
| Date: | Wednesday, February 28, 2018 | ||
| Abstract Number | 1320 - 8 | ||
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | Morning | ||
| Abstract | Chiral separations have traditionally been accomplished using cellulose/amylose based stationary phases and normal-phase chromatography. Although possible with some LC-MS sources, normal-phase solvents are often detrimental to ionization in those tandem systems, which limits enantiomeric separations in areas, such as bioanalysis, where LC-MS analysis is necessary. Besides the normal-phase used with cellulose and amylose polysaccharide chiral stationary phases is not compatible with biological samples. Macrocyclic glycopeptide chiral stationary phases are alternatives, which use typical reversed phase mobile phases or polar organic solvents, such as methanol, making them highly amenable for LC-MS analysis. In this study, we investigated the retention and selectivity on teicoplanin and vancomycin bonded silica phases using LC-MS method. We screened a set of basic probes differing in pKa values, hydrophobicity and molecular weight to probe the impact of buffer (salt) type, buffer concentration and acid/base ratio on retention, and selectivity. We then specifically investigated analysis of several beta-blocker drugs from rat plasma using MS-compatible mobile phases. It is demonstrated the methodology can be used in bioanalysis of clinical samples. The separation conditions and results will be discussed. | ||
| Poster Presentation | Title | Author | Co- Authors |
| Title | How combined new approaches can improve quantitative and qualitative LC-MS | Dave Bell | Stephan Altmaier |
| Date: | Wednesday, February 28, 2018 | Cory Muraco | Hans Griesinger |
| Poster # | 1320-1 | Michael Schulz | |
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | 10:00 AM – Noon | ||
| Abstract | Regulatory requirements regarding the limits of detection of various analytes have become increasingly challenging. In parallel, the performance of LC-MS instruments regarding sensitivity and resolution has improved tremendously in recent years. As a consequence, all steps of a typical LC-MS workflow have to be carried out carefully in order to avoid or minimize sample and system contamination. Quality of consumables (stationary phases, sample preparation devices), solvents and additives play an important role in gaining maximum sensitivity. System setup, consumables, eluent and additive handling and processing as well as stationary phase selection need thorough evaluation and novel approaches have to be made in order to meet these requirements. METHODS A novel approach was utilized to study the influence of column bleed of stationary phases on signal suppression, adduct formation and sensitivity drop in detail. Two options were taken into account in order to minimize these negative effects: - Implementation of a straightforward column washing process - Development of new stationary phase materials The result of both approaches was monitored using gradient HPLC-MS. Various HPLC-MS solvents as well as buffers were analyzed in terms of their purity utilizing flow injection analysis (FIA) or LC-MS on a standalone MS system. A FIA was further applied to analyze the pitfalls of solvent and additive handling and storage on sensitivity as well as on adduct formation and signal suppression of a model setup. PRELIMINARY DATA Cross-comparison of the “column bleeding” TIC of washed and unwashed columns was used to identify the effect of various washing processes on the column bleeding of various reversed phase HPLC columns. In this trial some untreated columns display severe bleed, making their use in MS applications impossible – mainly due to signal suppression or increased background noise. Washing with a mixture of isopropanol/formic acid minimized the bleeding effect and allowed for the combination of all reversed phases materials with state-of-the-art MS technology and without compromising system sensitivity. In an additional approach a new stationary phase for HILIC mode HPLC was developed. As was confirmed by LC-MS experiments, the level of column bleeding of this new material is negligible and no signal suppression or elevated background noise will compromise MS experiments. LC-MS solvents and additive solutions can be contaminated by improper handling, e.g. the use of plastic devices or of a dishwasher. Contaminations such as detergents, stabilizers or plasticizers were identified by MS and handling protocols were developed for a minimization of contamination during handling and to maximize sensitivity of analyses. A set of solvents and additives (acetonitrile, water, formic acid etc.) underwent various storage and handling treatments. The use of clear glass, amber glass and borosilicate glass bottles was investigated. Studies revealed the extraction of alkali from the two former vessels, resulting in severe adduct formation. As a result an innovative and economic glass container was developed. NOVEL ASPECT Storage/handling protocols and column washing procedure for low background noise/maximized sensitivity LC-MS analyses. Novel stationary phase material. |
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| Poster Presentation | Title | Author | Co- Authors |
| Title | New Ionic Liquid Stationary Phase Selectivity Evaluations | Len Sidisky | James L Desorcie |
| Date: | Thursday, March 01, 2018 | Greg A Baney | |
| Abstract Number | 1910-8 | Michael R Halpenny | |
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | Morning | ||
| Abstract | Ionic liquid stationary phases have been demonstrated to provide very unique selectivites compared to traditional polysiloxane or polyethylene glycol based phases. This selectivity is made possible due to the various combinations of cations and anions that are available along with spacer groups used to prepare these germinal dicationic phases. Columns prepared with di- or tricationic phases and newer phases that contain a PEG or branched chain alkyl linkage chain have the ability to perform many of the same applications as columns made with polysiloxane polymer or polyethylene glycol stationary phases of similar polarity, but with slight elution order changes. Many times this results in increased resolution and/or shorter run times. This paper will compare and contrast the selectivity of the ionic liquids stationary phases with traditional phases of similar or like selectivity’s for applications with a variety of different sample types from a number of industries including water analysis, petrochemical, pharmaceutical, environmental, food and beverage and flavor and fragrance. | ||
| Poster Presentation | Title | Author | Co- Authors |
| Title: | Quality Assurance in Karl Fischer Titration – how to produce reliable, precise and comparable results for the water content determination in raw materials and finished products and develop the right application. | Bettina Straub-Jubb | |
| Date: | Thursday, March 01, 2018 | ||
| Abstract Number | 1880-19 | ||
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | Morning | ||
| Abstract | Precise and accurate results of water contents are important for the quality of raw materials used in the production process and as well for the finished products. Whether you are determining the water content using the volumetric Karl Fischer titration or using a coulometric Karl Fischer instrument there are many aspects of the applied measurement method which require careful consideration to ensure that the results measured are accurately giving the water content in the sample. You will learn to fulfil compliance requirements and to develop your application to produce reproducible and comparable results. A correct pre-titration to eliminate the water in the titration cell and in the solvent as well as a precise titer determination or instrument check is an important precondition. How you can detect and avoid influences on your titration results will be discussed. With appropriate measures, you will be well prepared for quality assurance requirements and for internal and external audits. A further challenge is the individual development of the right application for each sample. An important aspect is the complete water release. Different techniques will be discussed. Dissolving the sample directly in the Karl Fischer solvent or do an internal or external extraction depends always upon the property of each sample. Additional solvents can improve the solubility of the sample. Heating up the medium or a dispersion can also support the water release. Disturbing side reaction can lead to false results and need to be recognized and suppressed. Each application need to be adapted individually to the sample with special techniques or reagents. We shall speak about how to develop the application, standardize the system and how to be prepared for the next audit. | ||
| Poster Presentation | Title | Author | Co- Authors |
| Title | Recent Research Developments in the Certification of Organic Reference Materials by 1H, 31P and 19F Quantitative NMR at the Highest Metrological Level. | Markus Obkircher | Christine Hellriegel |
| Date: | Thursday, March 01, 2018 | Alexander Rueck | |
| Location: | Room Exposition Floor, Aisles 2000-2700 | Romana Rigger | |
| Presenters Presence | Afternoon | ||
| Abstract | Quantitative NMR (qNMR) spectroscopy has become an important tool for the content determination of organic substances and the quantitative evaluation of impurities. Since the signal intensity is directly proportional to the number of protons contributing to the resonance, qNMR is considered as a relative primary method. Sigma-Aldrich R&D demonstrated the validity, robustness and precision of the 1H qNMR technique through the optimization of High-Performance qNMR (HP-qNMR®) to its maximum level of accuracy using metrological weighing equipment and a specially designed experimental setup for the certification of organic compounds with combined, expanded uncertainties down to 0.1%. The implementation of qNMR in new application fields (e.g. metabolomics, biomarker discovery, physiological pathways) brings along more complex molecules and systems, thus making the usage of 1H qNMR challenging. The use of other NMR active nuclei provides an elegant solution for which new qNMR standards are required. Therefore, we developed two additional classes of qNMR Certified Reference Materials (CRM), based on different NMR active nuclei. Figure 1 shows the certification concepts for 31P and 19F qNMR CRM to achieve traceability to the SI by using primary Reference Materials from the National Institute of Standards and Technology (NIST) and the National Metrology Institute of Japan (NMIJ). |
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| Poster Presentation | Title | Author | Co- Authors |
| Title | Novel Proficiency Testing Scheme for 1H, 31P and 19F Quantitative Nuclear Magnetic Resonance (qNMR) | Markus Obrkircher | Romana Rigger |
| Date: | Thursday, March 01, 2018 | Kathrin Breitruck | |
| Poster # | 2180-9 | Alexander Rueck | |
| Location: | Room Exposition Floor, Aisles 2000-2700 | ||
| Presenters Presence | Afternoon | ||
| Abstract | Quantitative NMR (qNMR) spectroscopy has become an important tool for the content determination of organic substances and the quantitative evaluation of impurities. Some years ago, we demonstrated validity, robustness and precision of the 1H qNMR technique through the optimization of High-Performance qNMR (HP-qNMR®) to its maximum level of metrological accuracy. The implementation of qNMR in new application fields (e.g. metabolomics, biomarker discovery, physiological pathways) brought along more complex molecules and systems that required additional classes of qNMR Certified Reference Materials (CRM), based on different NMR active nuclei, namely phosphorous and fluorine. | ||
Oral Presentations
| Oral Presentations | Title | Author | Co- Authors |
| Title | Certification of Marine Toxins by Quantitative NMR and Isotope Dilution MS at the Highest Metrological Level | Dr. Markus Obkircher | Christine Hellriegel |
| Date: | Tuesday, February 27, 2018 | Alexander Rueck | |
| Time: | 9:10 AM | Rudolf Koehling | |
| Location: | 205 B | Kathrin Breitruck | |
| Abstract | Since the presence of marine toxins in shell fish and sea food in general is an emerging problem, fast and sensitive LC-MS methods were established very recently for food testing. Therefore, the access to well characterized reference materials for a precise and accurate quantitation of these different toxins is now a crucial need of the testing laboratories. Unfortunately, the isolation, synthesis and purification of these compounds or their stable isotope labeled analogs is very challenging and lot sizes are typically in the range of few mg. In order to achieve certification of such small batches under ISO/IEC 17025 and ISO Guide 34 double accreditation at the highest metrological level, a combined setup of qNMR and Isotope Dilution MS was successfully established. In a first step, the concentration of a dissolved toxin is determined by a series of 1H-HP®-qNMR measurements. The received certified mass fraction is subsequently applied in an LC-IDMS experiment that results in a certified concentration for the stable isotope labeled analog. IDMS experiments are also carried out to determine the homogeneity and stability contribution to the overall uncertainty. The setup was validated by the defined and well characterized system caffeine-13C3-caffeine. An intra-laboratory comparison (3 persons, 3 days, 2 balances, 2 different reference solutions) of independently prepared caffeine/13C3-caffeine standards and sample solutions showed an overall variation +0.2/-0.2 µg/g of the measured concentrations. After demonstration of the robustness of the method, several saxitoxin derivatives were analyzed and certified using the same methodology. |
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| Oral Presentations | Title | Author | Co- Authors |
| Title | From A Pit to a Ladder: Strategies and Techniques for Improved Biomacromolecule Separations. | Cory Muraco | |
| Date: | Tuesday, February 27, 2018 | ||
| Time: | 11:05 AM | ||
| Location: | Room 308 B | ||
| Abstract | Separating proteins and antibodies is a unique analytical challenge owing itself to the complexity of the analytes. This complexity is a result of the myriad number of modifications to these analytes in a given sample including, but not limited to, phosphorylation, methylation, and glycosylation. Both heterogeneity and non-specific binding to the silica surface often result in extensive peak broadening and tailing. This seminar will focus on several different chromatographic strategies that the analytical scientist can employ to resolve and quantitate various biomacromolecules, including mAbs and ADCs. Selected aspects of size-exclusion, hydrophobic interaction, ion-exchange, hydrophilic interaction, and reversed-phase chromatography will be discussed. Finally, some aspects of method development will be presented to aid in the development of robust and reproducible analytical chromatographic schemes for the separations of protein and antibody mixtures. | ||
| Oral Presentation | Title | Author | Co- Authors |
| Title | Analysis of Bisphenol A in Foods using Solid Phase Microextraction with an Overcoated Fiber | Katherine K. Stenerson | Jennifer Claus |
| Date: | Tuesday, February 27, 2018 | ||
| Time: | 8:30 AM | ||
| Location: | Room 308B | ||
| Abstract | Bisphenol A (BPA) is a common component of food packing materials, including the linings of metal cans. While the safety of exposure to BPA is still under debate, public concern has increased regarding ingestion of this compound via packaged foods. Various methods have been used to analyze BPA in food, many using liquid/liquid extraction and/or solid phase extraction. In this work, solid phase microextraction (SPME) using an overcoated fiber was used for the immersion extraction of BPA from various packaged foods followed by GC/MS/MS analysis. The optimized SPME method was highly sensitive, allowing for low ppb level detection of BPA. The fiber used for the application consisted of divinylbenzene (DVB) overcoated with polydimethylsiloxane (PDMS). This overcoating allowed for direct immersion of the fiber into food matrices by protecting the DVB coating from sugars and fats present in the samples. A wash step after extraction was used to remove excess sample on the surface of the fiber, thus prolonging fiber life. Aspects of method development using the overcoated fiber, along with accuracy and reproducibility from several food matrices will be presented. |
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Venue Information
Orange County Convention Center – West
9800 International Dr, Orlando, FL 32819