Quantum-dot/aptamer-based ultrasensitive multi-analyte electrochemical biosensor.
The coupling of aptamers with the coding and amplification features of inorganic nanocrystals is shown for the first time to offer a highly sensitive and selective simultaneous bioelectronic detection of several protein targets. This is accomplished in a single-step displacement assay in connection to a self-assembled monolayer of several thiolated aptamers conjugated to proteins carrying different inorganic nanocrystals. Electrochemical stripping detection of the nondisplaced nanocrystal tracers results in a remarkably low (attomole) detection limit, that is, significantly lower than those of existing aptamer biosensors. The new device offers great promise for measuring a large panel of disease markers present at ultralow levels during early stages of the disease progress.
Department of Chemical and Material Engineering, Biodesign Institute, Arizona State University, Tempe, AZ 85287-5801, USA.
Jacob A
JA
Hansen
Joseph
J
Wang
Abdel-Nasser
AN
Kawde
Yun
Y
Xiang
Kurt V
KV
Gothelf
Greg
G
Collins
D052158:Aptamers, Peptide / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D007854:Lead / Q000737:chemistry; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry; D011506:Proteins / Q000032:analysis*; D045663:Quantum Dots; D012680:Sensitivity and Specificity; D013440:Sulfides / Q000737:chemistry
D052158:Aptamers, Peptide; D019187:Cadmium Compounds; D011506:Proteins; D013440:Sulfides; C034939:cadmium sulfide; C018391:lead sulfide; D007854:Lead