Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10534237 | Analytical Biochemistry | 2005 | 8 Pages |
Abstract
Fabrication of a capacitive immunosensor based on electropolymerized polytyramine (Pty) film for the direct detection of human serum albumin (HSA) without any labeling is described. The capacitance change of the heterostructures, Pty films/covalently bonded antibodies/buffered medium, is utilized for monitoring the specific antibody-antigen interaction. The Pty films are ultrathin and the HSA assay is nearly specific. Experimental parameters affecting antibody immobilization and the sensing of HSA are investigated in detail and optimized. This capacitive sensor prepared with the present method can provide high sensitivity. Under the optimized experimental conditions, a linear calibration curve in the concentration range 1.84-368.6Â ng/ml when plotted vs the logarithm of the antigen concentration is obtained and the detection limit (S/NÂ =Â 3) is 1.60Â ng/ml. After an acidic washing the present system can be used again. The applicability and reliability of the sensor are also demonstrated.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Zai-Sheng Wu, Ji-Shan Li, Ting Deng, Ming-Hui Luo, Guo-Li Shen, Ru-Qin Yu,