What's New with DART?
The latest developments and news on DART® Mass Spectrometry
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Greetings!, With the upcoming ASMS meeting in Minneapolis fast approaching, we want to let you know about our Customer Appreciation event scheduled for the evening of Wed, June 12. Please stop by our Booth #142 to pick up your ticket to this tasty event. Tickets are limited so come by early. We have obtained some very nice data recently on qualifying herbal supplements for their antioxidant content. This work was presented at the 2013 Ambient Ionization Mass Spectrometry Conference in Xaimen, China. Additionally if you are interested in the new DART® GSX™ for the Agilent ® GC/MSD, we are now running customer samples in our demo lab so please contact us if you would like information on submitting samples. And, of course, there are some interesting new publications on a variety of topics Please have a look and contact me if you have any questions or comments. Regards,  Brian Musselman President and CEO IonSense, Inc.
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Detecting Catechins in Teas and Herbal Supplements
 Over 150 Scientist gathered to discuss the latest advances in ambient ionization in the meeting organized by the Chinese Mass Spectrometry Society and co-organizer ASPEC Technologies. Presentations from 20 leading Chinese laboratories using ambient ionization methods showed results in a variety of areas such as traditional Chinese medicines, lipid profiling, pesticides, LC-coupling and imaging.
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Loading the XZ Transmission
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We presented our recent results on the challenging problem of the antioxidants in supplements and teas. Though direct analysis of teas and herbals with DART yields good ion signals for the caffeine and some carbohydrate peaks, we have utilized some simple solid phase extraction to enhance the signals for the higher molecular weight catechins and quercetins. Samples of brewed teas were pass through the MicroLiter C18 ITSP cartridges followed by a quick reaction with TriSiI-HTP. These samples were directly spotted on the screen of the 96 spot XZ Transmission Module. The spectra below left show the region of the spectra for the catechins, with the Oolong and AOAC Green teas giving good signals showing the presence of the desired antioxidants. In contrast the other locally purchased green tea shows nearly no signal for the species, indicating a much lower quality product. Similarity pomegranate herbal extracts from two sources are shown below, right. Clearly the GNC product has far more of the beneficial polyols than the "other" brand, which has nearly no signal for this region. Thus, this relatively simple sample derivatization approach rapidly yields important qualitative information on the presence or absence of important bioactive compounds in these dietary supplements. This approach should help many companies and testing labs as they continue to monitor and improve the quality of their raw as well as finished materials, under the new GMP requirements.   |
Have Your Samples Run on the NEW DART GSX
 | | The DART GSX System |
The new DART-GSX System enables rapid screening and characterization of samples on the Agilent GC/MSD, which is widely used in many of your labs For details on the GSX, you can download the brochure here The DART GSX System can be fitted to one of your existing Agilent GC/MSD instruments or it can be supplied as a complete system with a new or refurbished Agilent GC/MSD. If you are interested in having samples run on the demonstration unit in Saugus, please let us know. |
Recent DART Publications
In 2007, the United States Food and Drug Administration released guidance recommending testing of glycerin used in regulated consumer products, such as cough syrup preparations, toothpaste, and other pharmaceutical and food products, for the toxic compounds ethylene glycol and diethylene glycol. Regulatory laboratories routinely test glycerin, and products containing glycerin or related compounds for these toxic glycols, using an official gas chromatographic method, to ensure the safety of these products. The current work describes a companion technique to compliment this GC-FID method utilizing Orbitrap mass spectrometry with direct analysis in real time ionization to rapidly screen these samples qualitatively, with results in as little as five seconds, with no sample preparation required. This allows the more time and resource intensive method to be reserved for those rare cases when these compounds are detected, potentially greatly improving laboratory efficiency. The technique was evaluated for qualitative sensitivity and repeatability, and compared against the GC-FID method. The method appears to perform well against these metrics.
Stephanie Houlgrave, Gerald M. LaPorte, Joseph C. Stephens, Justin L. Wilson Forensic Services Division, United States Secret Service, Questioned Document Branch, Washington, DC; Office of Investigative and Forensic Sciences, National Institute of Justice, 810 Seventh Street, N.W., Washington, DC Large polarizable n-alkanes (approximately C18 and larger), alcohols, and other nonpolar compounds can be detected as negative ions when sample solutions are injected directly into the sampling orifice of the atmospheric pressure interface of the time-of-flight mass spectrometer with the direct analysis in real time (DART) ion source operating in negative-ion mode. The mass spectra are dominated by peaks corresponding to [M + O2]-. No fragmentation is observed, making this a very soft ionization technique for samples that are otherwise difficult to analyze by DART. Detection limits for cholesterol were determined to be in the low nanogram range.
Ashton D. Lesiak, Rabi A. Musah, Robert B. Cody, Marek A. Domin,c A. John Dane and Jason R. E. Shepard
Department of Chemistry, University at Albany, State University of New York (SUNY), Albany, USA, JEOL USA, Inc., Peabody, USA, Mass Spectrometry Center, Merkert Chemistry Center, Boston College, Chestnut Hill, USA
Rapid and versatile direct analysis in real time mass spectrometry (DART-MS) methods were developed for detection and characterization of synthetic cathinone designer drugs, also known as "bath salts". The speed and efficiency associated with DART-MS testing of such highly unpredictable samples demonstrate the technique as an attractive alternative to conventional GC-MS and LC-MS methods. A series of isobaric and closely related synthetic cathinones, alone and in mixtures, were differentiated using high mass accuracy and in-source collision induced dissociation (CID). Crime laboratories have observed a dramatic rise in the use of these substances, which has caused sample testing backlogs, particularly since the myriad of closely structurally related compounds are challenging to efficiently differentiate. This challenge is compounded by the perpetual emergence of new structural variants as soon as older generation derivatives become scheduled. Because of the numerous chemical substances that fall into these categories, along with the varying composition and complexity of mixtures of these drugs, DART-MS CID has the potential to dramatically streamline sample analysis, minimize the number of sample preparation steps, and enable rapid characterization of emerging structural analogs.
Tomas Cajka, Hana Danhelova, Milena Zachariasova, Katerina Riddellova, Jana Hajslova
Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, Institute of Chemical Technology, Prague, Technicka 3, 166 28, Prague 6, Czech Republic
Metabolomic fingerprinting enabled by ambient mass spectrometry employing a direct analysis in real time (DART) ion source coupled to a medium-high resolution/accurate mass time-of-flight mass spectrometer (TOFMS) was used as a tool for differentiation between chickens fed by feed that contained 5-8 % (w/w) of chicken bone meal (a banned component) and those representing a reference group, i.e. grown otherwise under the same conditions. In the first step, the sample extraction and DART-TOFMS instrumental conditions were optimized to obtain the broadest possible representation of ionizable compounds occurring in the extracts obtained from chicken muscle and feed on which experimental animals were grown. To this end, a simultaneous (all-in-one) extraction procedure was developed employing water and cyclohexane mixture as the extraction solvents. Under these conditions both polar as well as non-polar metabolites were isolated within a single extraction step. In the next step, metabolomic fingerprints of a large set of chicken muscle and feed extracts were acquired. In the final phase, the experimental data were statistically evaluated using principal component analysis and orthogonal partial least squares discriminant analysis. In general, differentiation of chicken muscle according to diet (feed with and without the addition of chicken bone meal) was feasible. Additional experiments conducted after 6 months confirmed applicability of this approach. Correct classification was obtained based on the assessment of polar as well as non-polar extracts fingerprints. However, the analysis of non-polar extracts showed that the pattern of triacylglycerols is more prone to seasonal variability and/or type of raw materials used during feed preparation which obscures the bone meal impact to some extent.
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Keeping Up With DART
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About IonSense
IonSense, Inc. provides OpenSpot Mass Spectrometry™ solutions to the fields of food safety, forensics, drug development, and chemical analysis. They manufacture and develop direct analysis in real time (DART®) technology licensed from JEOL USA, Inc. and atmospheric solids analysis probe (ASAP™) licensed from M&M Consulting.
DART and ASAP Sources are available for most commercial LC/MS systems. Look here to see if your system is DART-ready. And check here to see if your system is ASAP-ready.
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