Abstract
Graphene oxide (GO)-Chitosan (CHI) nano-composite is employed for the development of DNA based electrochemical biosensor for diagnosis of typhoid. Biosensor has been prepared by covalent immobilization of Salmonella typhi specific 5′-amine labeled single stranded (ss) DNA probe on GO-CHI/ITO via glutaraldehyde. Differential pulse voltammetry (DPV) studies revealed good specificity and ability of ssDNA/GO-CHI/ITO biosensor to distinguish complementary, non-complementary and one base mismatch sequences. The ssDNA/GO-CHI/ITO biosensor showed detection range of 10 fM to 50 nM and LOD 10 fM within 60 s hybridization times for complementary sequence. Further, ssDNA/GO-CHI/ITO bioelectrode is able to detect complementary target present in serum samples with LOD of 100 fM at 25 C. The excellent performance of biosensor is attributed to large surface-to-volume ratio and good electrochemical activity of graphene oxide, and good biocompatibility of chitosan, which enhances the DNA immobilization and facilitate electron transfer between DNA and electrode surface (ITO).
| Original language | English (US) |
|---|---|
| Pages (from-to) | 675-684 |
| Number of pages | 10 |
| Journal | Sensors and Actuators, B: Chemical |
| Volume | 185 |
| DOIs | |
| State | Published - 2013 |
Keywords
- Chitosan
- DNA
- Graphene oxide
- Nano composite
- Salmonella
- Typhoid
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry