The detection of cancer mutations in circulating tumor (ct)DNA/RNA in patient liquid biopsies has increasingly been shown to exhibit unique benefits for early detection or minimal residual disease monitoring. Yet, current clinically validated assays for ctDNA/RNA are still fundamentally challenged by insufficient detection sensitivity and specificity because of trace biomarker levels in high non-target background of highly similar native and variant NA sequences. To address these issues, this research focuses on innovatively using magnetic nanoparticles to enhance electrochemical biosensing of ctDNA/RNA at the electrode-biomolecule-electrolyte interfaces.1 The central research concept is the use of double-stranded NA sequences as biological scaffolds on magnetic particles to activate a dual DNA-intercalating/freely diffusing redox reporter system in direct proximity to the electrode surface. This “magneto-bioelectrocatalytic cycling” technique enables magnetic concentration of biotargets on the electrode surface to facilitate effective electron transfer, leading to electrochemical signal intensification. Magneto-bioelectrocatalytic cycling has been demonstrated for different ctDNA/RNA biomarkers and clinically focused applications, including biosensing of single nucleotide variants in ctDNA for targeted melanoma treatment,2 fusion genes in ctRNA for prostate cancer diagnosis and risk classification,3 and diverse RNA species quantification for prostate cancer recurrence monitoring.4 The outcomes of this research have shown the versatility of magneto-bioelectrocatalytic cycling for use in different molecular assay designs to tackle the critical biosensing challenges of ctDNA/RNA biomarkers in clinical liquid biopsy samples.