A group of biotech employees in Madison who used to work for EMD Chemicals, formerly Novagen, a company that made test kits used for scientific research, were snapped up by Semba Biosciences. Semba develops scientific equipment that helps purify substances used for purposes such as drug development and research, and for the food industry. The prototype for Sembaâ??s Octave system was developed by Anil Oroskar, a UW-Madison chemical engineering graduate who founded Semba.