|What's New with DART?
The latest developments and news on DART® Mass Spectrometry
We hope you are off to a good start in the New Year.
We will be at the upcoming AAFS meeting and welcome you to stop by if you are attending.
Additionally we are pleased to announce that Susan Ryan has joined IonSense to provide a stronger connection between our US customers and IonSense. She will be responsible for sales in the US and will also work with our other representatives as well. Susan can be reached at firstname.lastname@example.org
so feel free to drop her a note if you have any questions about DART or ASAP products.
Also, there are some interesting new publications on a variety of topics from food packaging to aerosol particles.
Please have a look and contact me
if you have any questions or comments.
President and CEO
|See DART at the AAFS Annual Meeting|
IonSense will be attending the American Academy of Forensic Sciences (AAFS) 65th Annual Meeting February 18-23, 2013 in Washington, D.C. We will be exhibiting the latest in DART at the Exhibition, Booth 405. Additionally we are presenting some new and exciting results in the Toxicology Poster Session entitled:
Direct Analysis in Real Time (DART) Analysis With a Modified GC/MS System for Rapid Drug Screening
We will be highlighting some of our recent work on the coupling of DART with the Agilent GC/MS instrument. Initial results are exciting and we will have more to share on this next month. Let us know if you'd like us to send you some information on this.
If you are interested in the activities at the meeting, you can download the preliminary program here.
|Recent DART Publications|
Non-visible print set-off of photoinitiators in food packaging: detection by ambient ionization mass spectrometry
K. Bentayebab, L.K. Ackerman, T. Lord & T.H. Begley
US Food and Drug Administration (USFDA), Center for Food Safety and Applied Nutrition, College Park, MD, 20740, USA, Dept. Anal. Chem., University of Zaragoza, María de Luna 3, 50018, Zaragoza, Spain, Smithers Pira, Cleeve Road, Leatherhead, Surrey, KT22 7RU, UK
Direct Analysis in Real Time coupled to Time of Flight Mass Spectrometry (DART/TOF-MS) was used to detect the non-visible set-off of photoinitiators on the food contact surface of three different packages. The samples were intentionally under-cured to provoke set-off. Twelve commercially available photoinitiators were included in the ink formulations including α-amino-, morpholino, and α-hydroxy benzophenones, thioxanthones, aryl-phosphine oxide and three polymeric versions of these. Major colors of the packages' prints were analyzed, as well as the specific areas of the inner surface in contact with them. Larger quantities of photoinitiators were detected on the food contact areas in contact with the darker colors of the images. Speed-cure 7005 and 4-phenylbenzophenone were the compounds most susceptible to set-off in each of the samples by DART response. An identification protocol for unknown set-off compounds was tested resulting in the set-off detection of diethylene glycol ethers, erucamide and acrylates, and confirmed by solvent extraction GC-MS analysis. Finally, DART/TOF-MS was scanned across transects of the food contact side of packages to map the presence of photoinitiators. Higher photoinitiator signals were observed in patterns corresponding to the printed image, suggesting DART/TOF-MS might 'image' print set-off.
Lukas Vaclavik, Anamika Mishra, Kumud B. Mishra, Jana Hajslova
Institute of Chemical Technology, Prague, Department of Food Analysis and Nutrition, Technická 3, 166 28, Prague, Czech Republic, CzechGlobe-Global Change Research Centre AS CR, v.v.i., Division of Impact Studies and Physiological Analyses, Laboratory of Plant Ecological Physiology, Zámek 136, 373 33, Nové Hrady, Czech Republic
The availability of rapid and reliable tools for monitoring of plants' cold tolerance is a prerequisite for research aimed at breeding of cold-tolerant crop plants. Therefore, we have tested the capacity of metabolomics-based methods employing ultra-high-performance liquid chromatography (UHPLC)-mass spectrometry and direct analysis in real time-mass spectrometry for high-throughput screening of cold tolerance in eight differentially cold-tolerant accessions of Arabidopsis thaliana. Metabolomic fingerprinting of leaf tissues was performed in methanolic extracts for (1) 6-week-old non-acclimated (NAC) plants grown at room temperature, (2) NAC plants cold-acclimated (ACC) at 4 °C for 2 weeks, and (3) cold-acclimated plants given sub-zero-temperature treatments by slow cooling at −4 °C for 8 h. The generated chromatograms and mass spectra were processed with the use of multivariate statistical analysis employing principal component analysis (PCA) and linear discriminant analysis. The PCA of metabolomic fingerprints classified the investigated A. thaliana accessions into three categories with low, intermediate, and high cold tolerance for both the cold-acclimated and the sub-zero-temperature-treated plants. This indicates the potential application of metabolomics-based fingerprinting for measuring cold tolerance in the cold-acclimated state, i.e., without treating plants at freezing temperatures that is required by currently available methods. Furthermore, we employed UHPLC coupled to the quadrupole-time-of-flight mass spectrometry to identify characteristic metabolites in ACC state and found the abundance of gluconapin and flavon-3-ol glycosides, respectively, in the cold-sensitive and the cold-tolerant accessions.
Shanshan Zeng, Teng Chen, Lu Wang, Haibin Qu
Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
Batch-to-batch variability of traditional Chinese medicine (TCM) has already heavily limited its industrial development. By utilizing direct analysis in real time mass spectrometry (DART-MS) and multivariate statistical analysis, the present study introduced a novel and rapid methodology for TCM manufacturing process monitoring. Danshen alkaline precipitation was employed as an example operating unit to demonstrate the effectiveness of this new technique. A total of 15 batches run under normal operating conditions were used to develop a reference principal component analysis model and then enabled the establishment of multivariate control charts. Hotteling T2 and DModX charts were applied to examine batch-to-batch reproducibility of 12 test batches. Artificial variations including starting material change and process fault were identified, which was in a good agreement with conventional analysis result. Further understanding of the deviating process behavior was achieved by investigating the contribution plot of abnormal batches. The results showed that DART-MS, in conjunction with multivariate analysis, provided valuable information on model process and gave us a new perspective for TCM manufacturing process monitoring.
Real Time In Situ Chemical Characterization of Sub-micron Organic Particles Using Direct Analysis in Real Time Mass Spectrometry (DART-MS)
Theodora Nah, ManNin Chan, Stephen R Leone, and Kevin R. Wilson
Direct analysis in real time mass spectrometry (DART-MS) is used to analyze the chemical composition of nanometer-sized organic aerosol particles in real time at atmospheric pressure. By introducing a stream of particles in between the DART ionization source and the atmospheric pressure inlet of the mass spectrometer, the aerosol is exposed to a thermal flow of helium gas containing some fraction of metastable helium atoms. In this configuration, the molecular constituents of organic particles are desorbed, ionized and detected with reduced molecular ion fragmentation, allowing for compositional identification. Aerosol components that are detected include alkanes, alkenes, acids, esters, alcohols, aldehydes and amino acids. The ion signal produced by DART-MS scales with the aerosol surface area rather than particle volume, suggesting that DART-MS is a viable technique to measure the chemical composition of the particle interface. For oleic acid, particle size measurements of the aerosol stream exiting the ionization region suggest that the probing depth depends upon the desorption temperature. The probing depth is observed to depend upon desorption temperature and is estimated to be on the order of 5 nm for a 185 nm diameter particle at a DART heater temperature of 500 °C. The reaction of ozone with sub-micron oleic acid particles is measured to demonstrate the ability of this technique to identify products and quantify reaction rates in a heterogeneous reaction.
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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.