Rapid and ultrasensitive detection of disease-specific biomarkers from liquid biopsy enables transformative approaches in clinical diagnostics. MicroRNAs have emerged as a highly promising class of short (~22 nt) non-coding RNA which hold great promise as clinical biomarkers due to their gene regulatory functions and dysregulated patterns in many diseases including cancer. Due to their low circulating concentrations and high sequence homology, however, microRNA detection often necessitates complex amplification-based strategies as well as bulky equipment and trained personnel. To this end, this talk introduces two platforms for rapid and amplification-free electrochemical detection of microRNA based on bespoke peptide nucleic acid (PNA) probe-functionalized 2D nanomaterials. PNAs are synthetic oligonucleotides that offer greater thermodynamic stability, specificity, and resistance to degradation compared to their natural counterparts. Considering their robustness, time efficiency, outstanding analytical performance, and amplification-free nature, the advanced platforms demonstrate immense potential to revolutionize point-of-care diagnostics while being key drivers of precision medicine.