Nanofibers mat as sampling module of direct analysis in real time mass spectrometry for sensitive and high-throughput screening of illegally adulterated sulfonylureas in antidiabetic health-care teas

In this work, novel ionic liquid (IL) functionalized polyacrylonitrile nanofibers mat (IL/PAN–NFsM) was firstly prepared through thiol–ene “click” reaction and evaluated for the establishment of a sensitive and high-throughput screening method. Because of its excellent pre-separation efficiency, IL/PAN–NFsM can adsorb trace-level targets from complex sample matrix within tens of seconds by performing a solid-phase extraction (SPE) process, and then served as sampling modules of direct analysis real time mass spectrometry (DART–MS) without any additional processing. This means the target analytes concentrated on IL/PAN–NFsM were directly desorbed, ionized, and detected by DART–MS. To verify the feasibility of the proposed method, three illegal added synthetic drugs (gliclazide, glimepiride , and gliquidone) were screened in six types of antidiabetic health-care tea samples. The results indicated that the sensitivity is in the level of ng g −1 , while total analysis time does not exceed 1.0 min per sample. Moreover, the stability expressed as relative standard deviation (RSD) varies from 1.7% to 17.3%. We proposed a new screening mode based on the direct combination of functionalized NFsM and DART–MS, which is expected to become a universal method in food safety analysis.