Biosensor Based On Lipid Bilayers Modified By Au Nanoparticle For The Electrochemical Detection Of Penicillin G Residues In Milk

With widespread use of antibiotics in animal husbandry, there are growing concern about antibiotic residues in food of animal origin (such as milk). As consumers and government realized the importance of animal origined food safety, residue detection method for various antibiotics, developed rapidly.Penicillin G is often used for prevent and treat bacterial infections of cows, so there is often some penicillin G residue in milk. Long-term consumption of milk containing penicillin G residues can cause a lot of harm. Therefore, the European Union (EC) and the U.S. Food and Drug Administration (FDA) have drafted strict rules about foods of animal origin, which expressly prohibited penicillin G residues in excess of the maximum residue limits (MRL) in milk Market.Traditionally, the analysis of penicillin G residues are based on microbiological analysis methods and physical chemical analysis methods.In this study, penicillin G by antibodies are immobilized in the gold nanoparticles modified solid supported bilayer lipid membrane (Supported Bilayer Lipid Membrance, s-BLM), and to establish an immunosensor for electrochemical detection of penicillin G.The properties of the modified electrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Our results demonstrated that the biosensor was able to detect penicillin G with an acceptable linear correlation ranging from 0.1 to 500 ng/mL and a detection limit of 0.08 ng/mL. When the biosensor was applied to milk samples, good results were obtained.