Spear Bio is developing an ultrasensitive immunodiagnostics and proteomics platform. Based on technology its founders developed and licensed from Harvard University: the Successive Proximity Extension Amplification Reaction (SPEAR), it allows the detection of single digit counts of protein molecules in tiny sample volumes, down to a tenth of a microliter. Whether measuring low abundance biomarkers with microsampling techniques or carrying out a multitude of tests on precious samples with limited volumes, it can become a solution for both research applications and minimally invasive diagnostics.