Surface Desorption Atmospheric Pressure Chemical Ionization Mass Spectrometry for Direct Detection of Ascorbic Acid in Beverages

A novel method was developed for direct detection of ascorbic acid in beverages by surface desorption atmospheric pressure chemical ionization mass spectrometry(SDAPCI-MS) without any sample pretreatment.Using sample needle sampling,the volume of each sampling was less than 5 nL.The average time for a single sample analysis was less than 0.5 min.The limit of detection for ascorbic acid is 1.9×10-9 g·mL-1,and the linear range is 10-8—10-3 g·mL-1.The recoveries for four samples spiked with 10-4 g·mL-1 ascorbic acid are in the range of 89.9%—109.6%,and the relative standard deviations in the range of 3.2%—5.8%.