Electrochemical molecular analysis without nucleic acid amplification.
Electrochemical biosensors have revolutionized glucose monitoring but have not yet fulfilled their promise of a low cost, direct detection replacement for genetic amplification tests such as PCR [K. Kerman, M. Kobayashi, E. Tamiya, Recent trends in electrochemical DNA biosensor technology, Meas. Sci. Technol. 15 (2004) R1-R11; A. Chaubey, B.D. Malhotra, Mediated biosensors. Biosens. Bioelectron. 17 (6-7) (2002) 441-456]. It has been anticipated that the integration of nanoscale chemical structures such as self-assembled monolayers with electrochemical biosensors would increase sensitivity by decreasing inherent system noise. We have designed a novel biosensing approach incorporating such integration and achieved rapid, ultra-low concentration sensitivities without target amplification. Raw samples are mixed with lysis buffer to allow hybridization of nucleic acid targets with anchor and signal probes before immobilizing a signaling enzyme proximate to the biosensor surface. A bias potential is subsequently applied and the secondary byproduct of a cyclic peroxidase reaction measured. Further studies have demonstrated the application of our approach in protein, clinical chemistry, and ionic assays.
Gau
Vincent
V
GeneFluidics, Inc., 2540 Corporate Place, B101, Monterey Park, CA 91754, USA. vgau@genefluidics.com
Ma
Shu-Ching
SC
Wang
Hua
H
Tsukuda
Joni
J
Kibler
John
J
Haake
David A
DA
D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis; D004563:Electrochemistry; D007118:Immunoassay; D021141:Nucleic Acid Amplification Techniques
D004247:DNA