title: Fenugreek hydrogel-agarose composite entrapped gold nanoparticles for acetylcholinesterase based biosensor for carbamates detection.
abstract: A biosensor was fabricated to detect pesticides in food samples. Acetylcholinesterase was immobilized in a novel fenugreek hydrogel-agarose matrix with gold nanoparticles. Transparent thin films with superior mechanical strength and stability were obtained with 2% fenugreek hydrogel and 2% agarose. Immobilization of acetylcholinesterase on the membrane resulted in high enzyme retention efficiency (92%) and a significantly prolonged shelf life of the enzyme (half-life, 55 days). Transmission electron microscopy revealed that, gold nanoparticles (10-20 nm in diameter) were uniformly dispersed in the fenugreek hydrogel-agarose-acetylcholinesterase membrane. This immobilized enzyme-gold nanoparticle dip-strip system detected various carbamates, including carbofuran, oxamyl, methomyl, and carbaryl, with limits of detection of 2, 21, 113, and 236 nM (S/N = 3), respectively. Furthermore, the fabricated biosensor exhibited good testing capabilities when used to detect carbamates added to various fruit and vegetable samples.
authors: Institute of Food Science and Technology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei, Taiwan, ROC.
authors: Rakesh Mohan
authors: RM
authors: Kestwal
authors: Institute of Food Science and Technology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei, Taiwan, ROC.
authors: Dipali
authors: D
authors: Bagal-Kestwal
authors: Institute of Food Science and Technology, National Taiwan University, No. 1, Roosevelt Road, Section 4, Taipei, Taiwan, ROC. Electronic address: bhchiang@ntu.edu.tw.
authors: Been-Huang
authors: BH
authors: Chiang
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry*; D000818:Animals; D001628:Beverages / Q000032:analysis*; D002219:Carbamates / Q000032:analysis*; D004593:Electrophorus; D004800:Enzymes, Immobilized / Q000737:chemistry; D005504:Food Analysis / Q000379:methods; D005506:Food Contamination / Q000032:analysis; D006046:Gold / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D010575:Pesticides / Q000032:analysis*; D012685:Sepharose / Q000737:chemistry*; D029910:Trigonella / Q000737:chemistry*
chemical_list: D002219:Carbamates; D004800:Enzymes, Immobilized; D010575:Pesticides; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006046:Gold; D012685:Sepharose; D000110:Acetylcholinesterase
keywords: Acetylcholinesterase; Agarose; Carbamates; Fenugreek hydrogel; Gold nanoparticles; Pesticides