title: Development of tyrosinase biosensor based on quantum dots/chitosan nanocomposite for detection of phenolic compounds.
abstract: A sensitive and simple amperometric biosensor for phenols was developed based on the immobilization of tyrosinase into CdS quantum dots/chitosan nanocomposite matrix. The nanocomposite film with porous nanostructure, excellent hydrophilicity and biocompatibility resulted in high enzyme loading, and the tyrosinase (Tyr) immobilized in this novel matrix retained its activity to a large extent. The CdS quantum dots/chitosan nanocomposite film was characterized by scanning electron microscopy and electrochemical impedance spectroscopy, and the parameters of the various experimental variables for the biosensor were optimized. Under the optimal conditions, the designed biosensor displayed a wide linear response to catechol over a concentration range of 1.0×10(-9) to 2.0×10(-5)M with a high sensitivity of 561±9.7mAM(-1) and a low detection limit down to 0.3 nM at a signal-to-noise ratio of 3. The CdS quantum dots/chitosan nanocomposites could provide a novel matrix for enzyme immobilization to promote the development of biosensing and biocatalysis.
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China. Electronic address: enhan182@163.com.
authors.forename: En
authors.initials: E
authors.lastname: Han
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: He
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Jianrong
authors.initials: J
authors.lastname: Cai
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Xinai
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Modern Agricultural Equipment and Technology (MOE), Institute of Agricultural Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
authors.forename: Xiaoya
authors.initials: X
authors.lastname: Dong
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D057230:Limit of Detection; D014442:Monophenol Monooxygenase / Q000737:chemistry / Q000378:metabolism*; D053761:Nanocomposites / Q000737:chemistry*; D010636:Phenols / Q000032:analysis; D045663:Quantum Dots / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D019187:Cadmium Compounds; D004800:Enzymes, Immobilized; D010636:Phenols; D013440:Sulfides; C034939:cadmium sulfide; D014867:Water; D048271:Chitosan; D014442:Monophenol Monooxygenase
keywords: Amperometric detection; Nanocomposite; Phenolic compounds; Quantum dots