상세정보
학술지
Toxin Detection by Si Photosensitive Biosensors with a New Measurement Scheme
- 발행일
- 201111
- 출처
- Biosensors and Bioelectronics, v.29 no.1, pp.219-223
- ISSN
- 0956-5663
- 출판사
- Elsevier
- 협약과제
- 10MC2400, 프로그램 가능한 바이오 CMOS 전계형 소자, 성건용
- 초록
- We propose a new type of photosensitive biosensor with a CMOS compatible Si photodiode integrated circuit, for the high-sensitive detection of small mycotoxin molecules requiring competitive assay approach. In this work, a photodiode is connected to the gate of a field effect transistor (FET) so that the open circuit voltage (V OC) of the illuminated photodiode is transferred into the drain/source current (I DS) of the FET. The sensing scheme employs competitive binding of toxin molecules (within the sample solution) and toxin-BSA conjugates (immobilized on the photodiode surface) with Au-nanoparticle-labeled antibodies, followed by silver enhancement to generate opaque structures on the photodiode surface. By utilizing the non-linear dependence of the V OC on the light intensity, we can maintain a sufficiently high signal resolution at low toxin concentrations (with most of the incident light blocked) for the competitive assay. By monitoring the I DS of the FET whose gate is driven by the V OC, quantitative detection of Aflatoxin B1 has been achieved in the range of 0-15ppb. © 2011 Elsevier B.V.
- KSP 제안 키워드
- Aflatoxin B1, CMOS-compatible, Competitive assay, Field-effect transistors(FETs), High sensitive, High signal, Integrated circuit, Non-linear dependence, Open circuit voltage(VOC), Photosensitive biosensor, Sensing scheme