水溶性量子点标记狂犬病P蛋白单克隆抗体的研究

利用共价偶联的方式,在水溶性缩合剂1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐(EDC)和N-羟基硫代琥珀酰亚胺(Sulfo-NHS)促进作用下,将400 μL的2 g/L狂犬病P蛋白抗体与适量的聚丙烯酸修饰后的水溶性硫脲修饰ZnO掺Cd量子点进行共价偶联反应,经磷酸盐缓冲液(PBS,0.01 mol/L,pH 7.4)透析纯化得到目标偶联物,采用荧光发射光谱、生物质谱、酶联免疫法等对偶联物进行表征.结果表明:偶联后的量子点荧光最大发射波长红移了10 nm,荧光强度随着狂犬病P蛋白抗原浓度的增加而逐渐增强；量子点标记狂犬病P蛋白抗体后的分子离子峰在m/z 67580处,比狂犬病P蛋白抗体分子离子峰增大了1453.由此证实狂犬病P蛋白抗体成功偶联到水溶性量子点上,且结构未受破坏.

Study of Rabies Protein Antibodies Marked with Water-Soluble Quantum Dots

With water-soluble carbodiimide(1-(3-dimethylaminopropyl)-3-ethylcarbodiimidehydrochloride,EDC) and N-hydroxysulfosuccinimide(Sulfo-NHS)as condensation agents,the rabies P protein monoclonal antibody(400 μL,2 g/L) was covalently coupled to the thiourea modified water-soluble Cd doped ZnO quantum dots which was further modified with polypropylene acid.The purified conjulate was obtained after the dialysis in the phosphate buffered solution(PBS,pH 7.4,0.01 mol/L).The rabies P protein monoclonal antibody was coupled to water-soluble quantum dots(QDs) with covalent coupling method.The conjulate was characterized by fluorescence emission spectrometry,bio-mass spectro-metry and enzyme-linked immunosorbent assay.The results showed that the main peak of the coupled QDs red shifted for 10 nm,the fluorescence intensity increased with the concentration increase of rabies P protein monoclonal antigen,and the molecular ion peak of the rabies P protein monoclonal antibody marked with QDs was m/z 67580,which was larger 1453 than that of rabies P protein monoclonal antibody.It was confirmed that the rabies P protein monoclonal antibody was successfully coupled to the water-soluble quantum dots,and the structures kept intact.