title: Surface-enhanced Raman scattering detection of cholinesterase inhibitors.
abstract: A new sensitive surface-enhanced Raman scattering (SERS) assay for detection of cholinesterase inhibitors such as organophosphorous pesticides using silver colloidal nanoparticles was developed and optimized. Acetylcholinesterase (AChE) mediated the hydrolysis of acetylthiocholine to produce thiocholine, which interacted with the silver nanoparticles to give a specific SERS spectrum. Variation in enzyme activity due to inhibition was measured from changes in intensity of a characteristic peak (772 cm(-1)) of the SERS spectrum that was directly correlated with the concentration of produced thiocholine. The method was demonstrated for the detection of paraoxon as reference AChE inhibitor. Limit of detection of paraoxon for 5 min incubation at 25 °C was 1.8×10(-8) M. This assay can be utilized for the detection of trace amounts of any AChE inhibitor.
authors: Department of Physical Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness-Ziona 74100, Israel. zvil@iibr.gov.il
authors: Zvi
authors: Z
authors: Liron
authors: Adi
authors: A
authors: Zifman
authors: Vered
authors: V
authors: Heleg-Shabtai
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry* / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000032:analysis*; D053768:Metal Nanoparticles / Q000737:chemistry; D010261:Paraoxon / Q000032:analysis; D010575:Pesticides / Q000032:analysis; D012834:Silver / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013860:Thiocholine / Q000378:metabolism
chemical_list: D002800:Cholinesterase Inhibitors; D010575:Pesticides; D012834:Silver; D013860:Thiocholine; D000110:Acetylcholinesterase; D010261:Paraoxon