The transport samples were analyzed by an Aijiren LC system (Aijiren Technologies, CA, USA) after redissolving with 50 μL methyl into vial inserts (100 uL; Aijiren Technologies, CA, USA). The separation was performed on an Octadecylsilyl (ODS) reversed-phase column (4.6 mm i.d. × 250 mm, 4.5 μm; TC-C18, Aijiren Technologies) using a diode