Startup Aplife Biotech is tapping into the rapidly growing market for biosensors that can expand the capacity of hand-held devices to screen for thousands of pathologies from a single drop of blood. Using technology developed in Argentina to print DNA structures on microchips, the company’s goal is to screen as many as 20 million probes with the potential to convert molecular interactions into electrical signals, opening a path for med-tech developers and manufacturers to explore new solutions for personalized health care.