Amperometric biosensor based on tyrosinase immobilized onto multiwalled carbon nanotubes-cobalt phthalocyanine-silk fibroin film and its application to determine bisphenol A.
An amperometric bisphenol A (BPA) biosensor was fabricated by immobilizing tyrosinase on multiwalled carbon nanotubes (MWNTs)-cobalt phthalocyanine (CoPc)-silk fibroin (SF) composite modified glassy carbon electrode (GCE). In MWNTs-CoPc-SF composite film, SF provided a biocompatible microenvironment for the tyrosinase to retain its bioactivity, MWNTs possessed excellent inherent conductivity to enhance the electron transfer rate and CoPc showed good electrocatalytic activity to electrooxidation of BPA. The cyclic voltammogram of BPA at this biosensor exhibited a well defined anodic peak at 0.625 V. Compared with bare GCE, the oxidation signal of BPA significantly increased; therefore, this oxidation signal was used to determine BPA. The effect factors were optimized and the electrochemical parameters were calculated. The possible oxidation mechanism was also discussed. Under optimum conditions, the oxidation current was proportional to BPA concentration in the range from 5.0 x 10(-8) to 3.0 x 10(-6) M with correlation coefficient of 0.9979 and detection limit of 3.0 x 10(-8) M (S/N=3). The proposed method was successfully applied to determine BPA in plastic products and the recovery was in the range from 95.36% to 104.39%.
Yin
Huanshun
H
College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong, China.
Zhou
Yunlei
Y
Xu
Jing
J
Ai
Shiyun
S
Cui
Lin
L
Zhu
Lusheng
L
D001559:Benzhydryl Compounds; D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D005349:Fibroins / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D057230:Limit of Detection; D014442:Monophenol Monooxygenase / Q000737:chemistry* / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D010636:Phenols / Q000032:analysis*; D015203:Reproducibility of Results; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D004800:Enzymes, Immobilized; D005349:Fibroins; D007211:Indoles; D014442:Monophenol Monooxygenase; D037742:Nanotubes, Carbon; D009942:Organometallic Compounds; D010636:Phenols; C482288:fibroin, silkworm; C063633:cobalt phthalocyanine; C006780:bisphenol A; D000098826:Bisphenol A Compounds