Objective To develop a rapid multi-residue assay for detecting 16 demanded by the European Union （EU）. Methods A recombinant penicillin-binding protein （PBP） 2x＊ from Streptococcus pneumoniae R6 was expressed in ...Objective To develop a rapid multi-residue assay for detecting 16 demanded by the European Union （EU）. Methods A recombinant penicillin-binding protein （PBP） 2x＊ from Streptococcus pneumoniae R6 was expressed in vitro and six β-1actams were conjugated to HRP by four methods. A rapid multi-residue assay for β-1actams was established with PBP2x＊ and HRP-conjugate. Results PBP2x＊ was expressed and purified successfully and the ideal HRP-conjugate was identified. The multi-residue assay was developed. After optimization, penicillin G, ampicillin, amoxicillin, cloxacillin, dicloxacillin, oxacillin, nafcillin, cephalexin, ceftiofur, cefalonium, cefquinome, cefazolin, cefoperazone, cephacetrile, and cephapirin can be detected at levels below MRL in milk with simple pretreatment. Conclusion This assay developed can detect all 16 β-1actams demanded by the European Union （EU）. The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.展开更多
文摘Objective To develop a rapid multi-residue assay for detecting 16 demanded by the European Union （EU）. Methods A recombinant penicillin-binding protein （PBP） 2x＊ from Streptococcus pneumoniae R6 was expressed in vitro and six β-1actams were conjugated to HRP by four methods. A rapid multi-residue assay for β-1actams was established with PBP2x＊ and HRP-conjugate. Results PBP2x＊ was expressed and purified successfully and the ideal HRP-conjugate was identified. The multi-residue assay was developed. After optimization, penicillin G, ampicillin, amoxicillin, cloxacillin, dicloxacillin, oxacillin, nafcillin, cephalexin, ceftiofur, cefalonium, cefquinome, cefazolin, cefoperazone, cephacetrile, and cephapirin can be detected at levels below MRL in milk with simple pretreatment. Conclusion This assay developed can detect all 16 β-1actams demanded by the European Union （EU）. The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.
