Results
Title

Bionanoconjugates of tyrosinase and peptide-derivatised gold nanoparticles for biosensing of phenolic compounds.

Authors

Cortez, J.; Vorobieva, E.; Gralheira, D.; Osório, I.; Soares, L.; Vale, N.; Pereira, E.; Gomes, P.; Franco, R.

Abstract

Bionanoconjugates of the enzyme tyrosinase (TYR) and gold nanoparticles (AuNPs) functionalised with a peptide (CALNN) were produced in solution and characterised. The formation of stable TYR-AuNP:CALNN bionanoconjugates (BNCs) was supported by a decrease of the surface charge of the BNCs as determined by ζ-potential and an increase in hydrodynamic diameter as determined by Dynamic Light Scattering (DLS). UV/Vis studies of pH-induced aggregation revealed distinct protonation patterns for the BNCs when compared with AuNP:CALNN alone, further substantiating BNC formation. Activity studies of the BNCs for the reduction of di-phenols in solution indicated that TYR not only remains active after conjugation, but interestingly its activity in the BNCs is higher than for the free enzyme. In conclusion, AuNP:CALNN can provide a suitable platform for the immobilisation of TYR, leading to BNCs with increased enzyme activity and a wider pH working range, with promising uses in electrochemical biosensors for the detection of mono- and di-phenolic compounds.

Subjects

PHENOL oxidase; COLLOIDAL gold; PHENOLS; SOLUTION (Chemistry); HYDROGEN-ion concentration; BIOSENSORS; LIGHT scattering

Publication

Journal of Nanoparticle Research, 2011, Vol 13, Issue 3, p1101

ISSN

1388-0764

Publication type

Academic Journal

DOI

10.1007/s11051-010-0099-8