MicroRNAs (miRNAs) play essential roles in post-transcriptional gene expression and are also found freely circulating in bodily fluids such as blood. Dysregulated miRNA signatures have been associated with many diseases including cancer, and miRNA profiling from liquid biopsies offers a promising strategy for cancer diagnosis, prognosis and monitoring. Here, we develop size-encoded molecular probes that can be used for simultaneous electro-optical nanopore sensing of miRNAs, allowing for ultrasensitive, sequence-specific and multiplexed detection directly in unprocessed human serum, in sample volumes as small as 0.1 μl. We show that this approach allows for femtomolar sensitivity and single-base mismatch selectivity. We demonstrate the ability to simultaneously monitor miRNAs (miR-141-3p and miR-375-3p) from prostate cancer patients with active disease and in remission. This technology can pave the way for next generation of minimally invasive diagnostic and companion diagnostic tests for cancer.

Current methods for diagnosing drug-resistant tuberculosis are time consuming, resulting in delays in patients receiving treatment and in transmission onwards. They also require a high level of laboratory infrastructure, which is often only available at centralized facilities, resulting in further delays to diagnosis and additional barriers to deployment in resource-limited settings.

No abstract

No abstract