基于对羟基苯硫酚自组膜免疫传感器的研究

利用自组装技术将对羟基苯硫酚(4—HTH)固定在金片电极上,以1—乙基—3—(3—二甲氨基)碳二亚胺盐酸盐(EDC)和N—羟基硫代琥珀亚胺(NHS)作为活化剂,将羊抗—小鼠IgG以共价键形式固定在对羟基苯硫酚自组装单分子膜修饰的金片电极上,制备了一种免疫传感器。根据抗体与抗原之间特异反应前后引起的电极电位变化,对小鼠IgG进行定量测定。利用循环伏安法分别对裸金片电极、对羟基苯硫酚自组装膜、抗体膜、抗原膜进行了表征。结果表明:该免疫传感器灵敏度高、响应速度快、检测范围宽,其检测下限为0.2μg/L,检测范围为0.2~30μg/L,并可以再生、重复利用,寿命可达10 d左右

Study on direct potentiometric immunosensor based on 4-hydroxy thiophenol SAMs

An immobilization procedure of antibody on planar gold electrode is proposed.A pretreated planar gold electrode is first immersed in 4-hydroxy thiophenol(4—HTH) solution for self assembly through the Au-S covalent bond.Then,antibody(sheep-anti-mouse IgG) is immobilized by means of covalent coupling with the activation of 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride(EDC) and N-hydroxysulfosuccinimide(NHS).The sensitivity of the procedure is high with the detection limit of 0.2 μg/L and a linear range from 0.2~30 μg/L.The immunosensor can be regenerated and the life can keep 10 days.Every immobilized step on planar Au electrode is characterized using cyclic voltammograms,and the result proves the immobilizes steps are feasible.