Nanoparticles with Raman spectroscopic fingerprints for DNA and RNA detection.
Multiplexed detection of oligonucleotide targets has been performed with gold nanoparticle probes labeled with oligonucleotides and Raman-active dyes. The gold nanoparticles facilitate the formation of a silver coating that acts as a surface-enhanced Raman scattering promoter for the dye-labeled particles that have been captured by target molecules and an underlying chip in microarray format. The strategy provides the high-sensitivity and high-selectivity attributes of gray-scale scanometric detection but adds multiplexing and ratioing capabilities because a very large number of probes can be designed based on the concept of using a Raman tag as a narrow-band spectroscopic fingerprint. Six dissimilar DNA targets with six Raman-labeled nanoparticle probes were distinguished, as well as two RNA targets with single nucleotide polymorphisms. The current unoptimized detection limit of this method is 20 femtomolar.
Department of Chemistry and Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
YunWei Charles
YC
Cao
Rongchao
R
Jin
Chad A
CA
Mirkin
D004396:Coloring Agents; D004247:DNA / Q000032:analysis*; D016172:DNA Fingerprinting / Q000379:methods*; D036103:Nanotechnology; D020411:Oligonucleotide Array Sequence Analysis; D015345:Oligonucleotide Probes; D020641:Polymorphism, Single Nucleotide; D012313:RNA / Q000032:analysis*; D012542:Scattering, Radiation; D012834:Silver; D013059:Spectrum Analysis, Raman
D004396:Coloring Agents; D015345:Oligonucleotide Probes; D012834:Silver; D012313:RNA; D004247:DNA