title: Development of an enzyme-linked immunosorbent assay to detect benzylpenicilloic acid, a degradation product of penicillin G in adulterated milk.
abstract: To avoid detection of penicillin G, some producers/merchants illegally add beta-lactamase to milk to degrade it into benzylpenicilloic acid (BPA). This degradation product can cause allergic reactions in humans and, therefore, is a potential hazard to human health. To detect BPA in milk, we established a rapid direct competitive enzyme-linked immunosorbent assay (ELISA) with an IC(50) of 0.32 +/- 0.01 microg L(-1), and a detection limit of 0.030 +/- 0.002 microg L(-1). Matrix effects in the milk samples were easily eliminated by centrifugation and dilution. Recoveries were 72.75-93.25%. Also heat treatments of raw milk did not affect the detection of the BPA. To validate BPA-ELISA, the spiked milk samples were analyzed by ELISA and LC-MS; the results showed a strong correlation (r(2) = 0.99). Incurred samples obtained from Tianjin Entry-Exit Inspection and Quarantine Bureau (TJCIQ) were tested by BPA-ELISA. The results showed an almost 100% correlation (r(2) = 0.99) with the results supplied by the TJCIQ.
authors.affiliation: Tianjin University of Science and Technology, Tianjin, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yueming
authors.initials: Y
authors.lastname: Jiang
authors.forename: Shuo
authors.initials: S
authors.lastname: Wang
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002417:Cattle; D004350:Drug Residues / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D057230:Limit of Detection; D008892:Milk / Q000737:chemistry*; D010400:Penicillin G / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry*; D011817:Rabbits; D001618:beta-Lactamases / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases; C030990:benzylpenicilloic acid; D010400:Penicillin G