Hospitals Fund Potential Game-Changers in Health Tech

Luis F. Romo is chasing the startup dream, developing a device that disinfects operating rooms and stretchers by zapping them with ultraviolet rays. The 30-year-old Mr. Romo has a catchy name for his invention, “PurpleSun,” and a solid but untraditional backer: a hospital.

Northwell Health, of New Hyde Park, N.Y., has put about $3 million into Mr. Romo’s idea and may invest more in coming years. As hospital-acquired infections have become the scourge of modern institutions, Northwell officials are eager to put the germ-fighting...