Dr. Li’s laboratory is interested in developing point of care (POC) diagnostics to detect bacterial pathogens, particularly epidemic Clostridium difficle strains that are resistant to clindamycin, fluoroquinolones and metronidazole. These strains are recognized as the major cause of healthcare antibiotic-associated diarrhea. Their POC technology is based on molecular recognition elements that are made of synthetic DNA molecules (e.g. DNA aptamers and DNAzymes) and selected from synthetic random-sequence DNA pools using test-tube evolution experiments. These molecules are subsequently used to develop tests as simple as the classic litmus test for clinical use.