抗生素功能化金磁纳米探针的制备及其过氧化物模拟酶性能研究

Preparation of antibiotic functionalized gold-magnetic nanoprobes and the study of their mimic peroxidase properties

以抗生素替考拉宁(Teicoplanin, Teico)作为还原剂和稳定剂,还原吸附在羧基化四氧化三铁纳米粒子(Fe_3O_4)表面的氯金酸根离子(AuCl_4^-),常温(25℃)下制备得到抗生素功能化金磁纳米探针(Teico-Au-Fe_3O_4).通过紫外-可见光谱法、透射电子显微镜、能量色散光谱法、动态光散射等方法对所得抗生素功能化金磁纳米探针的形貌、结构、光学性质等进行表征,并研究了其生物活性及过氧化物模拟酶催化性能.结果表明,该探针对金黄色葡萄球菌(Staphylococcus aureus, S.aureus)有明显的抑菌活性,同时该探针具有过氧化物模拟酶催化活性,对酶底物3,3′,5,5′-四甲基联苯胺(tetramethylbenzidine, TMB)的米氏常数Km为0.879 mM;基于其生物活性及过氧化物模拟酶催化活性可初步应用于检测S.aureus.

Antibiotic functionalized gold-magnetic nanoprobes(Teico-Au-Fe3O4)were prepared under room temperature(25℃)by using antibiotic teicoplanin(Teico)as reducing agent and stabilizer to reduce chloroauric acid which is adsorbed on carboxylated ferriferrous oxide.The morphologies,structure and optical properties of the obtained Teico-Au-Fe3O4 nanoprobes were characterized by ultraviolet-visible spectroscopy,transmission electron microscope,energy dispersive spectrum,and dynamic light scattering etc.Then,their biological activity and mimic peroxidase catalytic activity were studied.It could be found that the Teico-Au-Fe3O4 nanoprobes showed obvious antibacterial activity against Staphylococcus aureus(S.aureus)and mimic peroxidase catalytic activity with Michaelis constant(Km)of 0.879 mM for the enzyme substrate 3,3′,5,5′-tetramethylbenzidine(TMB).And moreover,based on its biological activity and mimic peroxidase activity.The Teico-Au-Fe3O4 nanoprobes showed some preliminary application for the detection of S.aureus.