Bionanoconjugates of tyrosinase and peptide-derivatised gold nanoparticles for biosensing of phenolic compounds
- 361 Downloads
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.
KeywordsTyrosinase Gold nanoparticle Bionanoconjugate Biosensor Environmental pollutants
- Robb D (1984) Tyrosinase. In: Lontie R (ed) Copper proteins and copper enzymes, vol 2. CRC Press Inc., Boca Raton, pp 207–240Google Scholar
- Rodriguez-Lopez J, Tudela J, Varon R, Garcia-Carmona F, Garcia-Canovas F (1992) Analysis of a kinetic model for melanin biosynthesis pathway. J Biol Chem 267:3801–3810Google Scholar
- Wang SS (1973) Para-Alkoxybenzyl alcohol resin and para-Alkoxybenzyloxycarbonylhydrazide resin for solid-phase synthesis of protected peptide fragments. J Am Chem Soc 95:1328–1333Google Scholar