title: Influence of surface-active compounds on the response and sensitivity of cholinesterase biosensors for inhibitor determination.
abstract: The influence of non-ionogenic surfactants, i.e., Tween-20, Triton X-100 and PEG-10,000, on the response of cholinesterase-based potentiometric biosensors and their sensitivity towards reversible and irreversible inhibitors were investigated. Acetyl- and butyrylcholinesterases were immobilized on nylon, cellulose nitrate films and tracing paper and were introduced into an assembly of potentiometric biosensors. The effect of surface-active compounds depends on the hydrophilic properties and porosity of the enzyme support material and the inhibition mechanism. In the range 0.002-0.3% m/v the surfactants show a reversible inhibiting effect on biosensor response. At lower concentrations (down to 10(-4)% m/v) the surfactants alter the analytical characteristics of reversible and irreversible inhibitor determination. The use of surface-active additives improves the biosensor selectivity in multi-component media.
authors.affiliation: Kazan State University, Russia.
authors.forename: G A
authors.initials: GA
authors.lastname: Evtugyn
authors.forename: H C
authors.initials: HC
authors.lastname: Budnikov
authors.forename: E B
authors.initials: EB
authors.lastname: Nikolskaya
mesh_terms: D015374:Biosensing Techniques; D002800:Cholinesterase Inhibitors / Q000032:analysis*; D002802:Cholinesterases / Q000737:chemistry*; D004800:Enzymes, Immobilized; D011199:Potentiometry; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D002800:Cholinesterase Inhibitors; D004800:Enzymes, Immobilized; D013501:Surface-Active Agents; D002802:Cholinesterases