Biosensors & Bioelectronics
Detection of analytes on the zepto-molar (10^-^2^1M) level has been achieved using a field-effect bio-detector. By applying a gating voltage to enzymes immobilized on the working electrode of the detector, amplification of the biocatalytic current was observed. The amplification is attributed to the modification of the tunnel barrier between the enzyme and the electrode by the gating voltage-induced electric field which exists at the solution-electrode interface. The detection was demonstrated with the glucose oxidase (GOx)-glucose and alcohol dehydrogenase (ADH)-ethanol biocatalytic systems. Glucose at zepto-molar level was detected with zepto-molar detection resolution. Equivalently, 30 glucose molecules present in the sample were detected and the detection system responded distinctively to the incremental change in the number of glucose molecules in unit of 30 molecules. The enzyme's biospecificity was also preserved in the presence of the applied field. We present possible processes that could give rise to the electrical charges required to produce the observed current level.
Choi, Yongki and Yau, Siu-Tung, "Ultrasensitive Biosensing on the Zepto-Molar Level" (2011). Electrical Engineering & Computer Science Faculty Publications. 54.
Choi, Y., , & Yau, S. (2011). Ultrasensitive biosensing on the zepto-molar level. Biosensors and Bioelectronics, 26(7), 3386-3390. doi:10.1016/j.bios.2011.01.009
NOTICE: this is the author’s version of a work that was accepted for publication in Biosensors & Bioelectronics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Biosensors & Bioelectronics, 26, 7, (03-15-2011); 10.1016/j.bios.2011.01.009