Combining Functionalised Nanoparticles and SERS for the Detection of miRNA Biomarkers Related to a disease

MicroRNAs (miRNAs) are short non coding RNA with a length of 18 to 24 nucleotides found in plants, animals, and some viruses (Chang et al., 2004, Vigorito et al., 2007). They modulate protein expression by binding to complementary sequences of messenger RNA (mRNA) and are likely to be involved in most biological process by affecting gene regulation (Gauthier and Wollheim, 2006). They were discovered in the 1990s, however they were not recognised as a class of biological regulators until 2000. Since then, they have attracted a lot of attention for their potential use in the treatment and prevention of many diseases like cancer, cardiovascular diseases and type 2 diabetes. Many methods can be used for miRNA biomarkers detection but Surface Enhancement Raman Scattering (SERS) is considered to be fast, highly sensitive and an extremely effective technique for miRNA detection when used with bio-functionalised metallic nanoparticles. The development of an assay for miRNA detection using SERS is of great importance as it will open an avenue for treating many diseases through miRNA biomarkers. However, RNA is generally known for its chemical instability unlike DNA which is the most challenging problem associated with RNA. The assay designed for the miRNA detection should overcome this problem and develop a stable method for the detection of miRNA biomarkers. The overall project aim is to develop an assay for miRNA biomarkers detection using surface enhanced Raman spectroscopy (SERS). To achieve this objective, first we need to synthesis oligonucleotide-silver nanoparticle conjugates to use them as probes for RNA detection and then label them with a SERS active dye. A study of different dyes should be carried out to determine which one is most suitable for RNA detection by SERS.