Electrogenerated chemiluminescence biosensor with alcohol dehydrogenase and tris(2,2′-bipyridyl)ruthenium (II) immobilized in sol-gel hybrid material

An ethanol biosensor based on electrogenerated chemiluminescence detection was developed. Electrogenerated chemiluminescence reagent tris(2,2′- bipyridyl)ruthenium (II) and alcohol dehydrogenase were immobilized in the same sol-gel hybrid film. The copolymer poly(vinyl alcohol) with 4-vinylpyridine and cation exchanger Nafion were incorporated into sol-gel film to provide the microenvironment for retaining the activity of enzyme and immobilize tris(2,2′-bipyridyl)ruthenium (II). The design was simpler than the previous two-layer format. The experimental conditions, such as scan rate, pH and concentration of the cofactor were investigated. The intensity of electrogenerated chemiluminescence increased linearly with ethanol concentration from 2.5 × 10^-5 to 5.0 × 10^-2 M and detection limit was 1.0 × 10^-5 M. The prepared biosensor exhibited high sensitivity, wide linear range and good stability.