摘要

BACKGROUND: Bioreactors are widely used in the chemical, food and medical industries. However, enzyme immobilization in the bioreactor often results in the loss of activity and stability to varying degrees. To resolve the problem, a new functional conducting polymer monomer, 2,5-di(2-thienyl)-1H-pyrrole-1-(p-phenylacetic acid) (DPP), was designed, synthesized and electrodeposited on copper net to form ultrathin poly(DPP) film containing free carbonyl groups. Then, pseudomonas cepacia lipase was covalently coated on the film with 1-ethyl-3-(3-dimethyl-aminopropyl)-carbodiimide / N-hydroxy-succinimide as activator, and 1,3-di(isobutyl)-imidazolium hexafluorophosphate ionic liquid was finally coated on the surface of the film. In this study, an as-prepared bioreactor was employed for the resolution of (R, S)-1-phenylethanol to investigate catalytic characterization of the enzyme immoblized on the bioreactor. RESULTS: The enzyme immobilized on the bioreactor offers high activity, reactivity and stability. Under optimal conditions, initial reaction rate, the conversion of (R, S)-1-phenylethanol and enantiomeric excess of (R)-1-phenylethyl acetate was 1.76 U mg-1, 47.4% and 99%, respectively. Also, the stability of the lipase immobilized on the bioreactorwas 5.1-fold that of the native lipase in hexane. The lipase immobilized on the bioreactor was recycled 10 times without substantial diminution in activity. CONCLUSION: The functional conducting polymer combined with the ionic liquid for the enzyme immoblization provided good enzyme activity and stability. It is also promising for both the construction of bioreactors and industrialized continuous production.

全文