A schematic of the instrument is shown in Fig. 1. A 488-nm laser (Innova 200, Coherent Inc., Santa Clara, California) is focused by two cylindrical lenses onto a BD FACSCalibur flow cell with attached light collection lens (Becton Dickinson, San Jose, California). Side-scattered light is transmitted through a dichroic beam splitter (FF505-SD, Semrock, Rochester, New York) onto a Hamamastu (Bridgewater, New Jersey) R636-10 PMT. Fluorescence is reflected by the same dichroic, passed through a dove prism, dispersed by a spectrometer (f1.8i Holospec using a HVG-590 grating, Kaiser Optical Systems Inc., Ann Arbor, Michigan), and detected with a pixel electron multiplying charge coupled device (EMCCD) (Newton model DU970N-UVB, Andor Technology PLC., South Windsor, Connecticut). Forward-scattered light is quantified with an amplified detector (PDA100A, Thor Labs, Newton, New Jersey) equipped with a beam stop to block direct laser light.