Highly stable enzyme precipitate coatings and their electrochemical applications

Byoung Chan Kim, Xueyan Zhao, Hye Kyung Ahn, Jae Hyun Kim, Hye Jin Lee, Kyung Woo Kim, Sujith Nair, Erik Hsiao, Hongfei Jia, Min Kyu Oh, Byoung In Sang, Beom Soo Kim, Seong H. Kim, Yongchai Kwon, Su Ha, Man Bock Gu, Ping Wang, Jungbae Kim

Research output: Contribution to journalArticlepeer-review

51 Scopus citations


This paper describes highly stable enzyme precipitate coatings (EPCs) on electrospun polymer nanofibers and carbon nanotubes (CNTs), and their potential applications in the development of highly sensitive biosensors and high-powered biofuel cells. EPCs of glucose oxidase (GOx) were prepared by precipitating GOx molecules in the presence of ammonium sulfate, then cross-linking the precipitated GOx aggregates on covalently attached enzyme molecules on the surface of nanomaterials. EPCs-GOx not only improved enzyme loading, but also retained high enzyme stability. For example, EPC-GOx on CNTs showed a 50 times higher activity per unit weight of CNTs than the conventional approach of covalent attachment, and its initial activity was maintained with negligible loss for 200 days. EPC-GOx on CNTs was entrapped by Nafion to prepare enzyme electrodes for glucose sensors and biofuel cells. The EPC-GOx electrode showed a higher sensitivity and a lower detection limit than an electrode prepared with covalently attached GOx (CA-GOx). The CA-GOx electrode showed an 80% drop in sensitivity after thermal treatment at 50°C for 4. h, while the EPC-GOx electrode maintained its high sensitivity with negligible decrease under the same conditions. The use of EPC-GOx as the anode of a biofuel cell improved the power density, which was also stable even after thermal treatment of the enzyme anode at 50°C. The excellent stability of the EPC-GOx electrode together with its high current output create new potential for the practical applications of enzyme-based glucose sensors and biofuel cells.

Original languageEnglish (US)
Pages (from-to)1980-1986
Number of pages7
JournalBiosensors and Bioelectronics
Issue number5
StatePublished - Jan 15 2011


  • Biofuel cells
  • Biosensors
  • Carbon nanotubes
  • Electrospun polymer nanofibers
  • Enzyme precipitate coatings
  • Enzyme stabilization


Dive into the research topics of 'Highly stable enzyme precipitate coatings and their electrochemical applications'. Together they form a unique fingerprint.

Cite this