Oligonucleotide Labeling and Detection by SERRS

A number of methods for detecting specific DNA sequences have been used to provide data for diagnosis of diseases and examination of gene expression. The most favoured is fluorescence detection although the addition of fluorescent labels can be disadvantageous due to the complex and expensive labelling chemistry. In this work, a novel method of oligonucleotide labelling was devised and surface enhanced resonance Raman scattering (SERRS) used as a detection technique. A number of SERRS active dyes containing benzotriazole groups were prepared and attached to DNA using Diels Alder chemistry. Benzotriazole maleimide dye and fluorescein were used in the design of a novel class of biosensor named SERRS Beacons, in which both fluorescence and SERRS are utilized for detection of minute amounts of DNA in solution. Low detection limits, simplicity of both the labelling chemistry and SERRS surface preparation, makes SERRS an excellent technique for oligonucleotide detection with the possibility of use in the rapidly growing DNA microarray and proteomic area.