LAUSR

Abstract The toxicity of catechol, hydroquinone and resorcinol requires their determination at low concentration levels over a wide linear range. Therefore, in this work we present a new bio-sensing device fabricated by a Soft Plasma Polymerization (SPP) technique for the determination of dihydroxybenzene isomers in real water samples. The Corona SPP technique was applied to the deposition of a bio-recognition layer based on the laccase enzyme. In comparison to conventional methods of biosensor construction, application of the SPP technique allows reduction of its preparation time from several hours to ∼2 min with no chemical consumption. The fabricated biosensor was characterized to find the optimum experimental conditions and determine its response time, sensitivity, linear range and selectivity coefficient. The optimum environment of the bio-sensor for generation of catechol, hydroquinone and resorcinol oxidation peaks was found to be acetate buffer at pH = 6.13. The biosensor exhibited a wide linear response both to catechol, hydroquinone and resorcinol with good sensitivity and high regression coefficient. Further studies showed also that the fabricated biosensor can be successfully applied to simultaneous determination of hydroquinone and resorcinol as well as catechol and resorcinol.