Novel rapid method for visualization of extent and location of aerosol contamination during high-speed sorting of potentially biohazardous samples

Abstract

Containment of potentially biohazardous aerosols that result from high-speed sorting of human cells has been an increasingly important problem in analytical cytometry. The current method for assessing the efficiency of aerosol containment involves detection of aerosols containing sorted T4 bacteriophage on lawns of T4-susceptible Escherichia coli on plates that are placed in and around the sort area. Although this method is sensitive, it is time consuming and involves maintenance and handling of bacteria and sorting of bacteriophage that may themselves serve as sources of contamination for sorted viable human cells. Glo Germ (5-microm melamine copolymer resin beads), which are fluorescent under black light illumination, were sorted on a Beckman-Coulter Elite ESP sorter in order to visualize deposition of aerosols under normal and mock failure modes. Glo Germ was successfully used under both normal sorting conditions, as well as mock failure mode, to visualize aerosol formation. We have developed a method to examine aerosol containment using modified Glo Germ, a product used for teaching aseptic technique in hospitals, industry, restaurants, and schools. Use of this technique represents a rapid, inexpensive, qualitative analysis of the extent and location of aerosol contamination from cell sorters.