title: Reagent-less detection of a competitive inhibitor of immobilized acetylcholinesterase.
abstract: The interaction of monosulfonate tetraphenyl porphine (TPPS(1)) with immobilized acetylcholinesterase (AChE) yields a characteristic absorbance peak at 446 nm. Addition of acetylcholine iodide or the competitive inhibitor tetracaine to the immobilized TPPS(1)-AChE complex results in a decrease in absorbance intensity at 446 nm due to displacement of the porphyrin from the active site. The loss in intensity at 446 nm is linearly dependent on tetracaine concentration at levels below 100 ppb. Tetracaine concentrations as low as 300 ppt have been detected.
authors.affiliation: Department of Physics, Oklahoma State University, Stillwater, OK 74078, USA.
authors.forename: Brandy J
authors.initials: BJ
authors.lastname: White
authors.forename: J Andrew
authors.initials: JA
authors.lastname: Legako
authors.forename: H James
authors.initials: HJ
authors.lastname: Harmon
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D015374:Biosensing Techniques; D002800:Cholinesterase Inhibitors / Q000032:analysis* / Q000494:pharmacology; D004593:Electrophorus; D004800:Enzymes, Immobilized; D066298:In Vitro Techniques; D011166:Porphyrins / Q000378:metabolism; D013053:Spectrophotometry; D013748:Tetracaine / Q000032:analysis / Q000494:pharmacology
chemical_list: D002800:Cholinesterase Inhibitors; D004800:Enzymes, Immobilized; D011166:Porphyrins; D013748:Tetracaine; C016136:tetraphenylporphine sulfonate; D000110:Acetylcholinesterase