ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Immobilisation of acid pectinase on graphene oxide nanosheets

Yang Liu, Qiang Li, Yuan-Yuan Feng, Geng-Sheng Ji, Tian-Cheng Li, Jie Tu, and Xu-Ding Gu

School of Biology and Chemistry, Jiangsu University of Science and Technology, Zhenjiang, 212018, China

E-mail: biojustlq@gmail.com

Abstract: Recent progress in nanotechnology has prompted research interest in immobilised enzymes on graphene oxide (GO) nanosheets for their large specific surface area and abundant functional groups. In the present work, acid pectinase was immobilised on the GO via the cross-linking of amino groups on pectinase and functional groups (e.g. carboxyl group) on the GO surface. Acid pectinase was effectively immobilised on the support and high loading densities were obtained (2400 mg per g of support). In addition, the immobilised enzyme achieved a better catalytic efficiency (K_cat/K_m) than its free counterpart; 3.7 mg⁻¹ min⁻¹ mL for immobilised pectinase, 3.5 mg⁻¹ min⁻¹ mL for free pectinase. Under acidic conditions, pectinase immobilised on GO will be agglomerated, but the addition of surfactant PEG 6000 could solve the problem and afford higher catalytic activity and catalytic efficiency.

Keywords: graphene oxide – acid pectinase – enzyme immobilisation – dispersion – loading density

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-013-0510-x

Chemical Papers 68 (6) 732–738 (2014)