LONG KEY, Fla. — Hendrik Luesch, an assistant professor of medicinal chemistry at the University of Florida College of Pharmacy, sorts through the day’s diving samples of blue-green algae on June 11, 2010, during an expedition to the Florida Keys. Accompanied by students from his UF marine natural products lab, Luesch raced to collect new samples as environmental impacts from the migrating oil spill threatens Florida, closing their window on cancer-fighting drug discoveries.