Researchers have devised a tiny, nano-sized sensor capable of detecting protein biomarkers in a sample at single-molecule precision. Fittingly coined as ‘hook and bait,’ a tiny protein binder fuses to a small hole created in the membrane of a cell — known as a nanopore – which allows ionic solution to flow through it. When the sensor recognizes a targeted molecule, the ionic flow changes. This change in flow serves as the signal from the sensor that the biomarker has been found.