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PubMed · 12788556

Integrated capillary fluorescence DNA biosensor.

Marc A Breimer·Yevgeny Gelfand·Omowunmi A Sadik
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Abstract

Covalent attachment of dsDNA molecules inside a glass capillary without the need for hybridization is described. It is shown that the glass capillary has a surface density of 2.5 x 10(13) molecules/cm(2) with specific binding capacity of 62.5%. The resulting substrate was used to develop a biosensor for determining fluorescent organic analytes and metal binding with DNA. The biosensor combines highly specific immobilization chemistry with a capillary-geometry flow cell arrangement. The results show that fluorescent dyes are retained in the dsDNA-modified surface and that exposure to concentrations of nickel and lead ions resulted in a recoverable, highly reproducible diminishment of the fluorescence intensity.

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AdsorptionBiosensing TechniquesCapillary ActionDNADNA-Binding ProteinsEquipment DesignEquipment Failure AnalysisFlow Injection AnalysisFluorescence Polarization ImmunoassayFluorescent DyesLeadMicrofluidicsNickelReproducibility of ResultsSensitivity and SpecificityStaining and LabelingSystems IntegrationEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Validation Study

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Marc A Breimer, Yevgeny Gelfand, Omowunmi A Sadik. 2003-08-15. Integrated capillary fluorescence DNA biosensor.. https://doi.org/10.1016/s0956-5663(02)00248-8

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