Preparation of a composite film electrochemically deposited with chitosan and gold nanoparticles for the determination of alpha-1-fetoprotein.
A novel amperometric immunosensor based on chitosan-gold nanoparticles (Chit-GNPs) composite film and thionine (Thi) was prepared for the determination of alpha-1-fetoprotein (AFP). The immunosensor was prepared by electro-depositing a Chit-GNPs composite matrix on the surface of the glass carbon electrode, then Thi was immobilized onto the Chit-GNPs film using glutaraldehyde as a cross-linker. Furthermore, the GNPs were chemisorbed onto Thi film for immobilization of alpha-1-fetoprotein antibody. The procedure of the immunosensor was characterized by means of cyclic voltammograms. The performance and influencing factors of the resulting immunosensor were studied in details. Under optimal conditions, the immunosensor was highly sensitive to AFP and the linear range covered from 0.40 to 200.0 ng mL(-1) with a detection limit of 0.24 ng mL(-1) at three times background noise. Moreover, the simple and controllable electro-deposition method overcame the irreproducibility for preparing Chit-based immunosensor systems and the proposed immunosensor displayed a satisfactory reproducibility and stability.
Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, People's Republic of China. yaxiliu1986@126.com
Yaxi
Y
Liu
Ruo
R
Yuan
Yaqin
Y
Chai
Chenglin
C
Hong
Shu
S
Guan
D001681:Biological Assay / Q000379:methods*; D048271:Chitosan / Q000737:chemistry*; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry*; D006801:Humans; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry*; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis*
D008567:Membranes, Artificial; D000509:alpha-Fetoproteins; D006046:Gold; D048271:Chitosan