Improvement of an enzyme electrode by poly(vinyl alcohol) coating for amperometric measurement of phenol.
A poly(vinyl alcohol) film cross-linked with glutaraldehyde (PVA-GA) was introduced to the surface of a tyrosinase-based carbon paste electrode. The coated PVA-GA film was beneficial in terms of increasing the stability and reproducibility of the enzyme electrode. The electrode showed a sensitive current response to the reduction of the o-quinone, which was the oxidation product of phenol, by the tyrosinase, in the presence of oxygen. The effects of the PVA and PVA-GA coating, the pH, and the GA:PVA ratio on the current response were investigated. The sensitivity of the PVA-GA-Tyr electrode was 130.56microA/mM (1.8microA/microM cm(2)) and the linear range of phenol was 0.5-100microM. At a higher concentration of phenol (>100microM), the current response showed the Michaelis-Menten behavior. Using the PVA-GA-Tyr electrode, a two-electrode system was tested as a prototype sensor for portable applications.
Kim
Gha-Young
GY
Department of Environmental Science and Engineering, Gwangju Institute of Science & Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, South Korea.
Cuong
Nguyen Manh
NM
Cho
Seung-Hee
SH
Shim
Joonmok
J
Woo
Jung-Je
JJ
Moon
Seung-Hyeon
SH