Highly sensitive determination of aminoglycoside residues in food by sheathless CE-ESI-MS/MS

Aminoglycosides (AGs) are an important class of antibiotics that have a good bactericidal effect on Gram-positive and Gram-negative bacteria. Long-term consumption of AGs may cause many allergic reactions due to their high affinity to tissue. It is necessary to develop a sensitive and reliable analytical method for trace-level AGs in food. A capillary electrophoresis-electrospray ionization-tandem mass spectrometry (CE-ESI-MS/MS) method was established for the determination of AGs. High sensitivity was achieved by using a sheathless CE-MS interface and transient isotachophoresis. Under the optimized conditions, four AGs were separated by CE and quantified by MS detection with high sensitivity. The limit of quantitation for the four AGs in milk was 0.67 μg kg−1. The recoveries of the four AGs in spiked milk ranged from 76.20 to 110.00% with relative standard deviations of 7.25–13.73%. The results indicated that sheathless CE-ESI-MS/MS would be a sensitive and effective platform for AG detection in food.