Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7585036 | Food Chemistry | 2018 | 8 Pages |
Abstract
Rapid, direct, on-site and noninvasive food analysis is strongly needed for quality control of food. To satisfy this demand, the technique of dipping probe electrospray ionization/mass spectrometry (dPESI/MS) was developed. The sample surface was pricked with a fine acupuncture needle and a sample of â¼200â¯pL was captured at the needle tip. After drying the sample, the needle tip was dipped into the solvent for â¼50â¯ms and was moved upward. A high-voltage was applied to the needle to generate electrospray when the needle reached the highest position, and mass spectra were measured with a time-of-flight mass spectrometer. For evaluation of the method, the technique was used to analyze foods such as vegetables, salmon flesh, cow's milk, yogurt, and soy-bean milk. The detected major ions for cow's milk and yogurt were [(Lac)nâ¯+â¯Ca]2+ with nâ¯=â¯1-6 (where (Lac) is lactose), indicating that Ca2+ is tightly bound by Lac molecules.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Dilshadbek T. Usmanov, Mridul K. Mandal, Kenzo Hiraoka, Satoshi Ninomiya, Hiroshi Wada, Masaya Matsumura, Sachiyo Sanada-Morimura, Hiroshi Nonami, Shinichi Yamabe,