A simple, sensitive and selective ASAP® sample introduction approach to measuring the presence of two isobaric compounds, CBDA and THCA, contained in a complex sample such as hemp or cannabis plants or their corresponding extraction products. Measurements are made of differences in the relative composition of CBDA and THCA fragment ions originating from the same precursor ion. Applicability to screening plants and plant product materials such as hemp or marijuana to monitor out-of-specification composition is demonstrated.
This poster was presented at the 2018 Cannabis Science Conference in Portland, OR.
Authentic historic manuscripts fetch high sums, but establishing their authenticity is challenging, relies on a host of stylistic clues and requires expert knowledge. High resolution mass spectrometry has not, until now, been applied to guide the authentication of historic manuscripts. Robert Burns is a well-known Scottish poet, whose fame, and the eponymous ‘Burns Night’ are celebrated world-wide. Authenticity of his works is complicated by the ‘industrial’ production of fakes by Alexander Smith in the 1890s, many of which were of good quality and capable of fooling experts. This study represents the first analysis of the inks and paper used in Burns poetry, in a minimally destructive manner that could find application in many areas. Applying direct infusion mass spectrometry to a panel of selected authenticated Burns and Smith manuscripts, we have produced a Support Vector Machine classifier that distinguishes Burns from Smith with a 0.77 AUC. Using contemporary recipes for inks, we were also able to match features of each to the inks used to produce some of Burns’ original manuscripts. We anticipate the method and classifier having broad application in authentication of manuscripts, and our analysis of contemporary inks to provide insights into the production of written works of art.
The legalization of marijuana and hemp provides commercial opportunities as well as analytical challenges. Accurate and precise quantitative analysis of plant and medicinal products is needed in this new industry to document composition and assure the safety of cannabis products. LC/MS techniques can provide unparalleled selective and sensitive measurements for these purposes. Here we describe the use of a relatively inexpensive compact mass spectrometer for SIM LC/MS analysis of cannabis-related applications.
This poster was presented at ASMS 2018 Annual Conference in San Diego, CA.
The Touch Express™ Open Port Sampling Interface (OPSI), is designed for simple sampling of solids, liquids and sample preparation tips and fibers. The novel ambient sampling technique was developed by Gary Van Berkel and Vilmos Kertesz, of Oak Ridge National Laboratory.
Paired with the electrospray ion source of the expression® Compact Mass Spectrometer, the product incorporates a low volume, open port of continuously swept solvent, flowing directly into the electrospray ion source of the mass spectrometer.
During this webinar you will:
Learn how any soluble material touching the port is analyzed by the expression® Compact Mass Spectrometer in just seconds.
Learn how the sample technique eliminates sample preparation and provides zero carry over.
Find fast analysis methods for solids, liquids and sample preparation tips and fibers.
M.R. Chae, S.J. Kang, K.P. Lee, B.R. Choi, H.K. Kim, J.K. Park, C.Y. Kim, S.W. Lee
Onion (Allium cepa L.) and quercetin protect against oxidative damage and have positive effects on multiple functional parameters of spermatozoa, including viability and motility. However, the associated underlying mechanisms of action have not yet been identified. The aim of this study was to investigate the effect of onion peel extract (OPE) on voltage-gated proton (Hv1) channels, which play a critical role in rapid proton extrusion. This process underlies a wide range of physiological processes, particularly male fertility. The whole-cell patch-clamp technique was used to record the changes in Hv1 currents in HEK293 cells transiently transfected with human Hv1 (HVCN1). The effects of OPE on human sperm motility were also analyzed. OPE significantly activated the outward-rectifying proton currents in a concentration-dependent manner, with an EC50 value of 30 μg/mL. This effect was largely reversible upon washout. Moreover, OPE induced an increase in the proton current amplitude and decreased the time constant of activation at 0 mV from 4.9 ± 1.7 to 0.6 ± 0.1 sec (n = 6). In the presence of OPE, the half-activation voltage (V1/2 ) shifted in the negative direction, from 20.1 ± 5.8 to 5.2 ± 8.7 mV (n = 6), but the slope was not significantly altered. The OPE-induced current was profoundly inhibited by 10 μm Zn2+ , the most potent Hv1 channel inhibitor, and was also inhibited by treatment with GF109203X, a specific protein kinase C (PKC) inhibitor. Furthermore, sperm motility was significantly increased in the OPE-treated groups. OPE exhibits protective effects on sperm motility, at least partially via regulation of the proton channel. Moreover, similar effects were exerted by quercetin, the major flavonoid in OPE. These results suggest OPE, which is rich in the potent Hv1 channel activator quercetin, as a possible new candidate treatment for human infertility.
The LC/MS analysis was carried out using Advion Expression® CMS.
Raymond Glahn, Elad Tako, Jonathan Hart, Jere Haas, Mercy Lung’aho, Steve Beebe
This paper represents a series of in vitro iron (Fe) bioavailability experiments, Fe content analysis and polyphenolic profile of the first generation of Fe biofortified beans (Phaseolus vulgaris) selected for human trials in Rwanda and released to farmers of that region. The objective of the present study was to demonstrate how the Caco-2 cell bioassay for Fe bioavailability can be utilized to assess the nutritional quality of Fe in such varieties and how they may interact with diets and meal plans of experimental studies. Furthermore, experiments were also conducted to directly compare this in vitro approach with specific human absorption studies of these Fe biofortified beans. The results show that other foods consumed with beans, such as rice, can negatively affect Fe bioavailability whereas potato may enhance the Fe absorption when consumed with beans. The results also suggest that the extrinsic labelling approach to measuring human Fe absorption can be flawed and thus provide misleading information. Overall, the results provide evidence that the Caco-2 cell bioassay represents an effective approach to evaluate the nutritional quality of Fe-biofortified beans, both separate from and within a targeted diet or meal plan.
The LC/MS analysis was carried out using Advion Expression® CMS ESI.
P. Perez-Hurtado, E. Palmer, T. Owen, C. Aldcroft, M.H. Allen, J. Jones,,C.S. Creaser, M.R. Lindley, M.A. Turner, J.C. Reynolds
The rapid screening of volatile organic compounds (VOCs) by direct analysis has potential applications in the areas of food and flavour science. Currently, the technique of choice for VOC analysis is gas chromatography/mass spectrometry (GC/MS). However, the long chromatographic run times and elaborate sample preparation associated with this technique have led a movement towards direct analysis techniques, such as selected ion flow tube mass spectrometry (SIFT-MS), proton transfer reaction mass spectrometry (PTR-MS) and electronic noses. The work presented here describes the design and construction of a Venturi jet-pump-based modification for a compact mass spectrometer which enables the direct introduction of volatiles for qualitative and quantitative analysis.
The MS analysis was carried out using Advion Expression® CMS with vAPCI.
Vanilla extract is a baking staple for cookies, cupcakes and more – but not all vanilla extract is created equal. Pure vanilla extract is made from the vanilla bean pod of the Vanilla planifolia plant. Imitation vanilla is derived from ethyl vanillin, which can be synthesized without the use of any vanilla beans at all. While pure vanilla extract may seem like the obvious choice, it does come at a price, making the imitation product a viable option in supermarkets across the world. But it begs the question: what is the chemical difference, and are products marketed as “pure” truly authentic?
In this screening assay, the expression® CMS coupled with the Atmospheric Solids Analysis Probe (ASAP®) is used to quickly identify the presence of artificial vanilla, as well as confirm the purity of products marketed as such. This technique provides a fast and easy method for purity analysis.
A: Our group is interested in bacterial natural product chemistry, with projects ranging from the directed discovery of new natural products by genome mining and heterologous pathway expression, the elucidation of individual biocatalytic reactions by in vitro studies and the application of the respective biosynthetic enzymes in organic synthesis. This also involves significant synthetic work, for example to prepare enzyme substrates, validate natural product structure elucidation, or to realize chemo-enzymatic natural product total syntheses.
Q: WHAT WAS YOUR PREVIOUS WORK FLOW OR CHALLENGES?
A: While NMR spectroscopy is an analytical tool that is meanwhile accessible to chemical research practically at any time, making standard 1H NMR experiments available within minutes to few hours after a reaction work up, MS spectrometry can sometimes be challenging to conduct sufficiently fast to allow for an efficient work flow: MS equipment in academia is typically located in service units with relatively few machines for whole departments, often leading to waiting times of one to several days for an analysis. While MS would be the perfect tool to directly monitor the success of a chemical reaction in situ or to quickly evaluate the outcome of enzymatic transformations, above restrictions prevent this tool from being regularly and efficiently used.
Q: WHY DID YOU INCORPORATE THE EXPRESSION CMS INTO YOUR LABORATORY?
A: We integrated the expression CMS into our analytical equipment to obtain fast information on our synthetic and biocatalytic reactions, as well as on the content of whole bacterial raw extracts. While the machine is usually used for direct injections and for recording of MS spectra from TLC reaction controls using the Plate Express system, LC-MS measurements of enzymatic reaction set-ups and raw extracts are run overnight. To our surprise, even the detection of post-translational modifications on small proteins can accurately be detected with the CMS, providing us with an additional tool even for protein characterization. This now gives us fast initial MS data for all applications important to our lab, thus significantly streamlining our research work.
Q: WHO WOULD YOU RECOMMEND TO PURCHASE THE EXPRESSION CMS?
A: The expression CMS is the perfect MS system for any research laboratory involved in synthetic organic chemistry and chemical analytics of small molecules to proteins. The system is easy to use and maintain and can thus be used by many individuals. It is therefore particularly well-suited for academic research laboratories.
Bacteria can be benign, beneficial and harmful, for more than 70 years we have been combatting these microscopic creatures with antibiotics. Increasingly though strains of antimicrobial resistant bacteria are becoming commonplace. This has motivated numerous studies aimed at deciphering the evolution of antibiotic resistance. Volatile Organic Compounds (VOCs) are ubiquitous in nature and are produced through various metabolic and catabolic processes. The profile of bacterial VOCs could therefore offer an insight into the detection of the type of bacteria and how they grow. This research utilizes a Volatile Atmospheric Pressure Chemical Ionization (vAPCI) source coupled to a Advion CMS instrument for detection of bacterial VOCs from in-vitro samples. This rapid and non-invasive approach of sampling VOCs and the implementation of a metabolomics workflow discriminates between E.coli and staphylococcus aureus and demonstrates how bacterial profiles can change over time.
