title: Multi-wall carbon nanotube-polyaniline biosensor based on lectin-carbohydrate affinity for ultrasensitive detection of Con A.
abstract: In this paper, a novel method for detecting concanavalin A (Con A) was developed based on lectin-carbohydrate biospecific interactions. Multi-wall carbon nanotube-polyaniline (MWNT-PANI) nanocomposites, synthesized by in situ polymerization, were chosen to immobilize d-glucose through the Schiff-base reaction. The immobilized D-glucose showed high binding sensitivity and excellent selectivity to its target lectin, Con A. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were applied to characterize the assembly process of the modified electrode. Due to the high affinity of Con A for D-glucose and high stability of the propounded sensing platform, the fabricated biosensor achieved ultrasensitive detection of Con A with good sensitivity, acceptable reproducibility and stability. The changes of response current were proportional to the Con A concentrations from 3.3 pM to 9.3 nM, with a detection limit of 1.0 pM. Therefore, the combination of MWNT-PANI nanocomposites and the special binding force between lectin and carbohydrate provides an efficient and promising platform for the fabrication of bioelectrochemical devices.
authors.affiliation: Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, School of Chemistry and Chemical Engineering, Southwest University, Chongqing, China.
authors.forename: Fangxin
authors.initials: F
authors.lastname: Hu
authors.forename: Shihong
authors.initials: S
authors.lastname: Chen
authors.forename: Chengyan
authors.initials: C
authors.lastname: Wang
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.forename: Yun
authors.initials: Y
authors.lastname: Xiang
authors.forename: Cun
authors.initials: C
authors.lastname: Wang
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002241:Carbohydrates / Q000737:chemistry*; D003208:Concanavalin A / Q000737:chemistry / Q000302:isolation & purification*; D057230:Limit of Detection; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D000814:Aniline Compounds; D002241:Carbohydrates; D037742:Nanotubes, Carbon; C416807:polyaniline; D003208:Concanavalin A