Laccase immobilization over multi-walled carbon nanotubes: Kinetic, thermodynamic and stability studies

• Tipo: Artigo em Revista Científica Internacional
• Data: 2015

Autores

Ana P. M. Tavares (Autor) FEUP; Claúdia G. Silva (Autor) FEUP; Goran Drazic (Autor) Outra; Adrián M. T. Silva (Autor) FEUP; José M. Loureiro (Autor) FEUP; Joaquim L. Faria (Autor) FEUP

Revista

Título: Journal of Colloid and Interface Science

Vol. 454

Páginas: 52-60

ISSN: 0021-9797

Editora: Elsevier

Indexação

ISI Web of Knowledge - 69 Citações

ISI Web of Science

Scopus - 125 Citações

Current Contents

Classificação Científica

FOS: Ciências exactas e naturais > Química

CORDIS: Ciências Tecnológicas > Engenharia > Engenharia química

Projetos Associados

LSRE-LCM - Laboratório de Processos de Separação e Reação - Laboratório de Catálise e Materiais

Outras Informações

ID Authenticus: P-00G-4FV

DOI: 10.1016/j.jcis.2015.04.054

Abstract (EN): The biocatalytic performance of immobilized enzyme systems depends mostly on the intrinsic properties of both biomolecule and support, immobilization technique and immobilization conditions. Multi-walled carbon nanotubes (MWCNTs) possess unique features for enzyme immobilization by adsorption. Enhanced catalytic activity and stability can be achieved by optimization of the immobilization conditions and by investigating the effect of operational parameters. Laccase was immobilized over MWCNTs by adsorption. The hybrid material was characterized by Fourier transformed infrared (FTIR) spectroscopy, scanning and transmission electron microscopy (SEM and TEM, respectively). The effect of different operational conditions (contact time, enzyme concentration and pH) on laccase immobilization was investigated. Optimized conditions were used for thermal stability, kinetic, and storage and operational stability studies. The optimal immobilization conditions for a laccase concentration of 3.75 mu L/mL were a pH of 9.0 and a contact time of 30 min (522 U-lac/g(carrier)). A decrease in the thermal stability of laccase was observed after immobilization. Changes in Delta S and Delta H of deactivation were found for the immobilized enzyme. The Michaelis-Menten kinetic constant was higher for laccase/MWCNT system than for free laccase. Immobilized laccase maintained (or even increased) its catalytic performance up to nine cycles of utilization and revealed long-term storage stability.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 9