One of the most significant challenges facing analytical scientists is the accurate detection and quantification of trace levels of analyte. This can have enormous impact on a local environment, for example, early stage detection of disease, identifying disease markers, drug screening, water quality control, and chemical agents amongst others ultimately come down to the work of analytical scientists. These challenges are compounded when the analysis of real samples or even complex mixtures are required. With this in mind, a currently hotly pursued topic in nanoscale sciences is in the development of single molecule or near single molecule methods to improve quality of life by removing the “clouding” associated with ensemble averaging. Although strategies for detecting single molecules have existed for a number of years, efficient label-free methods without the need for chemical modification are lacking especially when considering smaller molecules directly in unprocessed clinical samples.
As Part of NanoPD we developed a number of nanopore-based systems for multiplexed detection directly in unmodified clinical samples. We have made substantial progress in technological developments, key achievments are as follows:
1. We have developed a strategy for detecting sepsis biomarkers, including PCT and let-7a miRNA, using nanopore sensing and AuNP/DNA molecular probes. Our results demonstrate that this strategy exhibits high sensitivity and selectivity in preclinical samples.
2. We successfully performed multiplexed detection of proteins and nucleic acids from patient samples for different variants of SARS-CoV-29 and Mpox virus. These results were achieved with minimal sample processing and ML-enabled classification using up to three barcoded probes.
3. By integrating dielectrophoretic trapping with nanopore sensing, we have enabled detection down to 5 fM concentrations, up to a 1000-fold improvement in the detection limit compared with existing methods while maintaining efficient throughput.
4. Nanopore sensing has been applied directly to patient samples to detect biomarkers for diseases such as prostate cancer and heart failure. We demonstrated proof-of-concept for the multiplexed detection of miRNAs, proteins, and small molecules, including the simultaneous detection of 40 miRNAs in human serum.
Multiplexed biomarker detection represents a transformative advancement with far-reaching implications for patients, healthcare providers, and society as a whole.