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PubMed · 12381369

Base pair mismatch recognition using plasmon resonant particle labels.

Steven J Oldenburg·Christine C Genick·Keith A Clark·David A Schultz
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Abstract

We demonstrate the use of silver plasmon resonant particles (PRPs), as reporter labels, in a microarray-based DNA hybridization assay in which we screen for a known polymorphic site in the breast cancer gene BRCA1. PRPs (40-100 nm in diameter) image as diffraction-limited points of colored light in a standard microscope equipped with dark-field illumination, and can be individually identified and discriminated against background scatter. Rather than overall intensity, the number of PRPs counted in a CCD image by a software algorithm serves as the signal in these assays. In a typical PRP hybridization assay, we achieve a detection sensitivity that is approximately 60 x greater than that achieved by using fluorescent labels. We conclude that single particle counting is robust, generally applicable to a wide variety of assay platforms, and can be integrated into low-cost and quantitative detection systems for single nucleotide polymorphism analysis.

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Base Pair MismatchBase SequenceBiotinylationBreast NeoplasmsDNAFemaleGenes, BRCA1HumansMolecular Sequence DataNucleic Acid HybridizationOligonucleotide Array Sequence AnalysisPolymorphism, Single NucleotideSensitivity and SpecificitySurface Plasmon ResonanceTemplates, GeneticComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Steven J Oldenburg, Christine C Genick, Keith A Clark, David A Schultz. 2002-10-01. Base pair mismatch recognition using plasmon resonant particle labels.. https://doi.org/10.1016/s0003-2697(02)00410-4

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