title: Improved DNA detection by utilizing electrically neutral DNA probe in field-effect transistor measurements as evidenced by surface plasmon resonance imaging.
abstract: Intensive efforts have been focused on the development of ultrasensitive DNA biosensors capable of quantitative gene expression analysis. Various neutralized nucleic acids have been demonstrated as alternative and attractive probe for the design of a DNA chip. However, the mechanism of the improvements has not been clearly revealed. In this investigation, we used a newly developed neutral ethylated DNA (E-DNA), a DNA analog with the "RO-P-O" backbone (wherein R could be methyl, ethyl, aryl, or alkyl group) obtained from synthetic procedures, and a silicon nanowire (SiNW) field-effect transistor (FET) to evaluate the difference in DNA detection performance while using E-DNA and DNA as probes. It is demonstrated that using the E-DNA probe in the FET measurement could have a significantly enhanced effect upon the detection sensitivity. Surface plasmon resonance imaging (SPRi) was used to evidence the mechanism of the improved detection sensitivity. SPRi analysis showed the amounts of probe immobilization on the sensor surface and the hybridization efficiency were both enhanced with the use of E-DNA. Consequently, neutral ethylated DNA probe hold a great promise for DNA sensing, especially in the electrical-based sensor.
authors.affiliation: Department of Chemical and Materials Engineering, National Central University, Jhong-Li 320, Taiwan. wychen@ncu.edu.tw
authors.forename: Wen-Yih
authors.initials: WY
authors.lastname: Chen
authors.forename: Hon-Chen
authors.initials: HC
authors.lastname: Chen
authors.forename: Yuh-Shyong
authors.initials: YS
authors.lastname: Yang
authors.forename: Chun-Jen
authors.initials: CJ
authors.lastname: Huang
authors.forename: Hardy Wai-Hong
authors.initials: HW
authors.lastname: Chan
authors.forename: Wen-Pin
authors.initials: WP
authors.lastname: Hu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000032:analysis / Q000235:genetics*; D015342:DNA Probes / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D015336:Molecular Probe Techniques / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055672:Static Electricity; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014173:Transistors, Electronic
chemical_list: D015342:DNA Probes; D004247:DNA