Preparation And Catalytic Properties Of Teicolanin Stabilized Pt And PdPt Nanoenzymes

Noble metal nanoparticles have a promising application prospect in catalytic detection.However,due to their poor stability and single function,their application is limited.The use of organic molecules as the stabilizer of noble metal nanoparticles is a suitable choice to improve the stability and enrich the function.In this study,Teicoplanin（Tei）was used as stabilizer to achieve uniform dispersion and function of noble metal nanoparticles.The structural characteristics and catalytic properties of Pt and Pd Pt nanozymes stabilized by teicoplanin were studied.The main contents and conclusions are as follows:Teicoplanin stabilized platinum nanoparticles（Pt-Tei NPs）were prepared.The results of Pt-Tei NPs aqueous solution detection by laser particle size analyzer showed that the hydrodynamic particle size of Pt-Tei NPs in PBS solution was 8-12 nm,which had good stability.Pt-Tei NPs had high peroxidase-like activity and can catalyze tetramethylbenzidine（TMB）,2,2-diazo-di-ammonium（3-ethyl-benzothiazol-6-sulfonic acid）（ABTS）and o-phenylenediamine（OPD）.The Michaelis constant of TMB catalyzed by Pt-Tei NPs was 0.0264 m M in catalytic kinetics experiments.Under the conditions of p H range 2-9,20℃-80℃,2 mg/m L sodium chloride solution,and storage for 7 days,the catalytic properties of Pt-Tei NPs were more than 80%.The detection range was 5-200μM,and the detection limit was 5.0173μM when detecting glutathione（GSH）with Pt-Tei NPs.The teicoplanin stabled platinum and palladium nanoparticles（Pd Pt₃-Tei NPs）were prepared by introducing palladium.Catalytic TMB experiments showed that the oxidase-like activity was the strongest when the molar ratio of palladium to platinum was1:3.The results showed that the hydrodynamic particle size of Pd Pt₃-Tei NPs was 10-20nm.Under storage conditions of 20℃-80℃or 7 days,the catalytic properties of Pd Pt₃-Tei NPs were about 80%.A method for the detection of sodium sulfite was developed with the detection limit of 8.521μM and the detection range of 5-175μM.Since lysine can inhibit the oxidase-like activity of Pd Pt₃-Tei NPs,a new method for the detection of lysine was developed.The detection range was 0.75-2.5 m M,and the detection limit was 0.457m M.In lysine solutions interfered with by reducing substances,the use of Pd Pt₃-Tei NPs can consume reducing substances and significantly increase the accuracy of lysine detection.