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Cl- sensitive biosensor used electrolyte-solution-gate diamond FETs.

Kwang-Soup Song·Toshikatsu Sakai·Hirofumi Kanazawa·Yuta Araki·Hitoshi Umezawa·Minoru Tachiki·Hiroshi Kawarada
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Abstract

We have investigated the electrolyte-solution-gate field effect transisitors (SGFETs) used hydrogen terminated (H-terminated) or partially oxygen terminated (O-terminated) polycrystalline diamond surface in the Cl- and Br- ionic solutions. The H-terminated channel SGFETs are insensitive to pH values in electrolyte solutions. The threshold voltages of the diamond SGFETs shift according to the density of Cl- and Br- ions about 30 mV/decade. One of the attractive biomedical applications for the Cl- sensitive SGFETs is the detection of chloride density in blood or in sweat especially in the case of cystic fibrosis. The sensitivities of Cl- and Br- ions have been lost on the partially O-terminated diamond surface. These phenomena can be explained by the polarity of surface change on the H-terminated and the O-terminated surface.

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Biosensing TechniquesChlorineDiamondElectrochemistryElectrolytesReproducibility of ResultsSensitivity and SpecificityTransistors, ElectronicComparative StudyEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tValidation Study

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Kwang-Soup Song, Toshikatsu Sakai, Hirofumi Kanazawa, Yuta Araki, Hitoshi Umezawa, Minoru Tachiki, Hiroshi Kawarada. 2003-11-15. Cl- sensitive biosensor used electrolyte-solution-gate diamond FETs.. https://doi.org/10.1016/s0956-5663(03)00174-x

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