Cancer is a leading cause of mortality worldwide, and important strategies to mitigate cancer burden include improved diagnostics for early detection and subsequent treat- ment. Among potential cancer biomarkers, microRNAs (miRNAs) are ideal for a rapid, minimally-invasive, and early-stage diagnostic with high disease specificity. MiRNAs are a robust class of small non-coding segments of RNA shown to exhibit altered expression profiles in different types of cancer. In addition, they are easily accessible in various bi- ological media (saliva, plasma, urine, etc.), and exist in highly stable forms resistant to nuclease activity and harsh conditions of pH and temperature. Herein we describe the first steps toward a sensitive and specific microfluidic-based detection platform for high- throughput profiling of miRNAs. We utilise 7-mer peptide nucleic acid (PNA) probes functionalized at the 51 and 31 ends with original optical probe heads. Detection occurs through miRNA-templated fluorogenic reactions of either trimethine cyanine dye (Cy3) synthesis or coumarin unquenching (fluorescence unmasking). Briefly, upon hybridiza- tion of the synthetic probes to a complementary nucleic acid target, both probe-heads are brought in close enough proximity to react with each other, thus generating the fluorescent product (while the reaction is highly unfavourable in the absence of nucleic acid template). The characteristic fluorescent signal emitted can therefore be directly linked to the detec- tion of the targeted sequence. In case of a partial or incomplete hybridisation of one of the probe (e.g. as a consequence of a SNP), a significant decrease in reaction efficiency (i.e. a weaker fluorescence) is observed. Thus far our system has shown sub-micromolar sensitivity and is compatible for detection in crude plasma, serum, and saliva samples with minimal pre-processing. Multiplexing can be achieved through simple modification of precursor moieties affording non-overlapping, multi-coloured system for the detection of different cancer biomarkers in parallel.