AMBIENTUM BIOETHICA BIOLOGIA CHEMIA DIGITALIA DRAMATICA EDUCATIO ARTIS GYMNAST. ENGINEERING EPHEMERIDES EUROPAEA GEOGRAPHIA GEOLOGIA HISTORIA HISTORIA ARTIUM INFORMATICA IURISPRUDENTIA MATHEMATICA MUSICA NEGOTIA OECONOMICA PHILOLOGIA PHILOSOPHIA PHYSICA POLITICA PSYCHOLOGIA-PAEDAGOGIA SOCIOLOGIA THEOLOGIA CATHOLICA THEOLOGIA CATHOLICA LATIN THEOLOGIA GR.-CATH. VARAD THEOLOGIA ORTHODOXA THEOLOGIA REF. TRANSYLVAN
|
|||||||
Rezumat articol ediţie STUDIA UNIVERSITATIS BABEŞ-BOLYAI În partea de jos este prezentat rezumatul articolului selectat. Pentru revenire la cuprinsul ediţiei din care face parte acest articol, se accesează linkul din titlu. Pentru vizualizarea tuturor articolelor din arhivă la care este autor/coautor unul din autorii de mai jos, se accesează linkul din numele autorului. |
|||||||
STUDIA CHEMIA - Ediţia nr.1-2 din 1999 | |||||||
Articol: |
AMPEROMETRIC STUDY OF THE INHIBITORY EFFECT OF BENZOIC ACID ON A TYROSINASE-MODIFIED PLATINUM ELECTRODE. Autori: SARMIZA ELENA STANCA, IONEL CĂTĂLIN POPESCU, LIVIU ONICIU. |
||||||
Rezumat: A new type of tyrosinase (PPO)-modified Pt electrode, based on physical entrapment of the enzyme in agar-agar gel, was constructed and used to investigate the inhibitory effect of benzoic acid on the PPO activity. At an applied potential of -50 mV vs. SCE, the bioelectrode develops a fast, steady state response, linearly correlated with the phenol concentration up to 0.1 mM, with a sensitivity of 4.2 mA.M-1.cm-2. A kinetic interpretation of the amperometric response to phenol recorded in the absence and in the presence of benzoic acid, allowed identifying the inhibition process as a competitive one. The inhibition constant, (1.16 0.01)*10-6 M, and inhibition coefficient, (1.24 0.15) 10-3 M, were found in good agreement with similar data published in the literature. | |||||||