title: Single-wall carbon nanotube-based voltammetric sensor and biosensor.
abstract: The pH-sensitive property of the single-wall carbon nanotube modified electrode based on the electroactive group on the single-wall carbon nanotube was explored by differential pulse voltammetry technique. In pH range 1-13 investigated in Britton-Robinson (B-R) buffer, the anodic peak shifted negatively along with the increase of pH exhibiting a reversible Nernstian response. Experiments were carried out to investigate the response of the single-wall carbon nanotube (SWNT) modified electrode to analytes associated with pH change. The response behavior of the modified electrode to ammonia was studied as an example. The potential response could reach equilibrium within 5 min. The modified electrode had good operational stability. Voltammetric urease and acetylcholinesterase biosensors were constructed by immobilizing the enzymes with sol-gel hybrid material. The maximum potential shift could reach 0.130 and 0.220 V for urea and acetylthiocholine, respectively. The methods for preparing sensor and biosensor were simple and reproducible and the range of analytes could be extended to substrates of other hydrolyases and esterases. This broadened the biosensor application of carbon nanotube in electrochemical area.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
authors.forename: Zhiai
authors.initials: Z
authors.lastname: Xu
authors.forename: Xu
authors.initials: X
authors.lastname: Chen
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Qu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Jia
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dong
mesh_terms: D000109:Acetylcholine / Q000032:analysis* / Q000737:chemistry; D000110:Acetylcholinesterase / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D017736:Ion-Selective Electrodes; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014508:Urea / Q000032:analysis* / Q000737:chemistry; D014510:Urease / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D014508:Urea; D000110:Acetylcholinesterase; D014510:Urease; D000109:Acetylcholine