A Focus on Microfluidics and Nanotechnology Approaches for the Ultra Sensitive Detection of MicroRNA

MicroRNAs are small RNAs that are deregulated under disease conditions. This allows them to be used as biomarkers for disease diagnosis. Recently, such microRNAs are serving as non- invasive blood based biomarkers due to ease of detection, and high stability at room temperature in biofluids. In view of these advancements in biomarker research, efficient miRNA detection at the femtomolar level is important. MiRNA detection techniques to date include Northern blotting, real time PCR and microarray technology. While these are efficient techniques, they cannot detect very low miRNA levels, and have questionable specificity. This review describes nanotechnology, microfluidics and liquid phase miRNA detection techniques that are highly sensitive and specific. With some sophistication, some of these techniques can be used as point of care devices to rapidly detect low level miRNA in patient clinical samples to aid disease diagnosis and prognosis.