Nitrogen-Doped Carbon Hollow Spheres for Immobilization, Direct Electrochemistry, and Biosensing of Protein.
- Resource Type
- Article
- Authors
- Zhang, Zhaohang; Zhang, Rong; Li, Cancan; Yuan, Liang; Li, Peipei; Yao, Li; Liu, Songqin
- Source
- Electroanalysis. Jun2012, Vol. 24 Issue 6, p1424-1430. 7p.
- Subject
- Language
- ISSN
- 1040-0397
Nitrogen-doped carbon hollow spheres (NCHS) were designed for the immobilization and biosensing of proteins. Chitosan was first functionalized with glutaraldehyde to form cross-linked chitosan with free CHO groups (GCS). The as-prepared GCS was used for dispersion of nitrogen-doped carbon hollow spheres. Using glucose oxidase (GOD) as a model, the NCHS was tested for immobilization of redox proteins and the design of electrochemical biosensors. GOD molecules immobilized in the nanocomposites showed direct electrochemistry with a formal potential of −0.448 V and well electrochemical performance. The proposed biosensor exhibited a linear response to glucose concentrations ranging from 3.7 µM to 18.0 mM with a detection limit of 1.2 µM and a sensitivity of 11.85 µA mM−1. This biosensor was also applied to detect glucose in human serum samples, accomplishing good recovery in the range of 92-105 %. The nanocomposites provided a good matrix for protein immobilization and biosensor fabrication. [ABSTRACT FROM AUTHOR]