Polyethyleneglycol diacrylate microspheres: a novel carrier for laccase immobilisation

Abstract

Laccase was immobilised on polyethyleneglycol diacrylate (PEGDA) microspheres. The optimal preparation conditions of PEGDA microspheres were as follows: 3.0% (w/v) 2,2-azobisisobutyro-nitrite (AIBN), 4.0–5.0% (w/v) polyvinylpyrrolidone (PVP), 5.0–8.0% (w/v) glucose and 4.0% (w/v) PEGDA in glucose solution. The volume ratio of PEGDA solution, glucose/PVP solution and AIBN solution was 25: 100: 1. Microspheres obtained exhibited good characteristics with small sizes (1–4 µm). The immobilised laccase showed a higher stability in a wide pH range. Thermal stability and storage stability of immobilised laccase were enhanced. The activity of immobilised laccase was 45.0% after six cycles uses. Only 62.7% of the activity remained for free laccase while there was a 60.4% increased for immobilised laccase with storage at 4 °C for 25 d. The K_m value of laccase increased from 21.9 to 114.0 µmol/l after immobilisation.

• Enzyme activity
• immobilisation
• laccase
• polyethyleneglycol diacrylate microspheres

Declaration of interest

The authors were supported by the Fundamental Research Funds for the Central Universities (2572014CA23) and China Postdoctoral Science Foundation (2013M541328). The authors report no declarations of interest.