title: Detection of caffeine in tea, instant coffee, green tea beverage, and soft drink by direct analysis in real time (DART) source coupled to single-quadrupole mass spectrometry.
abstract: Ambient ionization direct analysis in real time (DART) coupled to single-quadrupole MS (DART-MS) was evaluated for rapid detection of caffeine in commercial samples without chromatographic separation or sample preparation. Four commercial samples were examined: tea, instant coffee, green tea beverage, and soft drink. The response-related parameters were optimized for the DART temperature and MS fragmentor. Under optimal conditions, the molecular ion (M+H)+ was the major ion for identification of caffeine. The results showed that DART-MS is a promising tool for the quick analysis of important marker molecules in commercial samples. Furthermore, this system has demonstrated significant potential for high sample throughput and real-time analysis.
authors.affiliation: China Agricultural University, College of Science, Department of Applied Chemistry, Beijing, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Pengyue
authors.initials: P
authors.lastname: Zhao
authors.forename: Fengzu
authors.initials: F
authors.lastname: Zhang
authors.forename: Aijuan
authors.initials: A
authors.lastname: Bai
authors.forename: Canping
authors.initials: C
authors.lastname: Pan
mesh_terms: D002110:Caffeine / Q000737:chemistry*; D002253:Carbonated Beverages / Q000032:analysis*; D003069:Coffee / Q000737:chemistry*; D003198:Computer Simulation; D005504:Food Analysis; D013058:Mass Spectrometry / Q000379:methods*; D008962:Models, Theoretical; D015394:Molecular Structure; D013662:Tea / Q000737:chemistry*
chemical_list: D003069:Coffee; D013662:Tea; D002110:Caffeine