Ultrasensitive Biosensor for Detection of Organophosphorus Pesticides Based on a Macrocycle complex/carbon Nanotubes Composite and 1-methyl-3-octylimidazolium Tetrafluoroborate as Binder Compound

Neuma das Mercês Pereira, Fernando Mota de Oliveira, Nara Rúbia Pereira, Rodrigo Moreira Verly, Dênio Emanuel Pires Souto, Lauro Tatsuo Kubota, Auro Atsushi Tanaka, Flavio Santos Damos, Rita de Cássia Silva Luz

Anal Sci. 2015;31(1):29-35.

PMID: 25792271

Abstract:

This work describes the highly sensitive detection of organophosphorus pesticides employing the cobalt(II) 4,4,4,4-tetrasulfo-phthalocyanine (CoTSPc) macrocycle complex, carbon nanotubes (CNT), and 1-methyl-3-octylimidazolium tetrafluoroborate (OMIM[BF4]). The technique is based on enzyme acetylcholinesterase (AChE) inhibition. The composite was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and amperometry. The AChE was immobilized on the composite electrode surface by cross-linking with glutaraldehyde and chitosan. The synergistic action of the CoTSPc/CNT/OMIM[BF4] composite showed excellent electrocatalytic activity, with a low applied potential for the amperometric detection of thiocholine (TCh) at 0.0 V vs. Ag/AgCl. The calculated catalytic rate constant, k(cat), was 3.67 × 10(3) mol(-1) L s(-1). Under the optimum conditions, the inhibition rates of these pesticides were proportional to their concentrations in the ranges of 1.0 pmol L(-1) to 1.0 nmol L(-1) (fenitrothion), 2.0 pmol L(-1) to 8.0 nmol L(-1) (dichlorvos), and 16 pmol L(-1) to 5.0 nmol L(-1) (malathion).

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP244193520	1-Methyl-3-octylimidazolium tetrafluoroborate		244193-52-0	Price