Studies On Electrochemical And Electrochemiluminescence Immunosensors By The Signal Amplification Of Liposome

In recent years, the application of immunosensor is more and more extensively with the development of life sciences. Moreover, the further demands for the characteristics and testing methods of immunosensor have promoted the development of it. Electrochemical immunosensors have many advantages such as: selectivity, variety, not affected by the color and turbidity of samples, equipment required is relatively simple, fast. Electrochemiluminescence (ECL) immunosensor has both advantages of electrochemistry and chemiluminescence techniques by combining them, which possesses high sensitivity, wide linearity range, and high selectivity, simple and convenient. The aim of this work is to develop useful electrochemical and ECL immunosensor for clinical immunoassay based on liposome. The major contents in this thesis are described as follows:(1) A sandwich type ECL immunosensor was fabricated using Ru(bpy)₃²⁺- encapsulated liposome as the labels. Since a great number of reporter molecules could be contained in the liposomes, great signal amplification could be obtained and the sensitivity was improved. This immunosensor was used for ultrasensitive detection ofα-fetoprotein in human serum.(2) Based on the insulativity and induced steric hindrance effect of liposome, developed a sandwich type electrochemical impedance immunosensor. Liposome was used as signal enlargement to improve the detection sensitivity. This immunosensor was used for detection of human immune globulin G (IgG).(3) A sandwich type immunosensor was fabricated using Fe(CN)₆^4--encapsulated liposome as the label to detect IgG in human serum by square wave voltammetry (SWV) technique.