Hydroxyapatite nanoarray-based cyanide biosensor.
Here we report a simple, biomolecular-friendly protocol for the fabrication of a hydroxyapatite nanowires array (HANWA) biosensor of spatial positioning, large surface area, and abundant adsorbing sites and its application to cyanide sensing. The fabrication of HANWA is performed by template-assisted electrodeposition. The well-aligned hydroxyapatite nanoarray is composed of vertical nanowires with a diameter of approximately 200 nm and an average length of 1 microm. The electrochemical biosensor for the determination of cyanide through its inhibitory effect on horseradish peroxidase (HRP) encapsulated by chitosan (CHIT) on the platform of HANWA is demonstrated. The current organic-inorganic hybrid nanostructure provides excellent enzyme-substrate contact with enzyme activity well maintained. The densely distributed HANWA with large surface area and abundant adsorbing sites can provide a favorable electrochemical interface for the construction of electrochemical biosensor. A sensitive detection limit of 0.6 ng ml(-1) was obtained for cyanide. The proposed CHIT-HRP/HANWA biosensor has the advantages of spatial resolution, high sensitivity, rapid regeneration, and fast response associated with individual nanowires. It broadens the possible applications of chemosensors and biosensors, and it offers an alternative method for toxic substance determination. The new device holds great promise for environmental and food industrial monitoring of toxins.
Wang
Suiping
S
State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, People's Republic of China.
Lei
Yong
Y
Zhang
Yun
Y
Tang
Jian
J
Shen
Guoli
G
Yu
Ruqin
R
D001672:Biocompatible Materials / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D048271:Chitosan / Q000737:chemistry; D003486:Cyanides / Q000032:analysis* / Q000494:pharmacology; D017886:Durapatite / Q000737:chemistry*; D004553:Electric Conductivity; D004563:Electrochemistry; D004579:Electron Transport; D004595:Electroplating; D004791:Enzyme Inhibitors / Q000032:analysis / Q000494:pharmacology; D006735:Horseradish Peroxidase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D053770:Nanowires / Q000737:chemistry*; D010539:Permeability
D001672:Biocompatible Materials; D003486:Cyanides; D004791:Enzyme Inhibitors; D048271:Chitosan; D017886:Durapatite; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase