Ultrasensitive electrical biosensing of proteins and DNA: carbon-nanotube derived amplification of the recognition and transduction events.
A new strategy for dramatically amplifying enzyme-linked electrical detection of proteins and DNA using carbon nanotubes (CNTs) for carrying numerous enzyme tracers and accumulating the enzymatically liberated product on CNT-modified transducer is described. Such a CNT-derived double-step amplification pathway (of both the recognition and transduction events) allows the detection of DNA and proteins down to 1.3 and 160 zmol, respectively, in 25-50 muL samples and indicates great promise for PCR-free DNA analysis. The new protocol is illustrated for monitoring sandwich hybridization and antibody-antigen interactions in connection with alkaline-phosphatase tracers. The DNA-linking of CNTs and particles holds promise also for assembling hybrid nanostructures relevant to molecular electronic devices.
Wang
Joseph
J
Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico 88003, USA.
Liu
Guodong
G
Jan
M Rasul
MR
D000469:Alkaline Phosphatase / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis*; D008280:Magnetics; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011199:Potentiometry / Q000379:methods; D011506:Proteins / Q000032:analysis*; D012680:Sensitivity and Specificity
D037742:Nanotubes, Carbon; D011506:Proteins; D004247:DNA; D000469:Alkaline Phosphatase