By Gary Partington
Isolators have been around the Pharmaceutical Industry since the early 1980s and in the Nuclear Industry (glovebox technology) since the 1950s. The intent of isolators is to create an airtight barrier or enclosure around a piece of equipment or process which provides absolute separation between the operator and product. The operator can perform tasks through half-suits or glove ports. Isolators provide a specific environment inside the isolator using HEPA filters. The environment can be positive pressure or negative, can have humidity control, oxygen control, use unidirectional airflow, and can either protect the product from the operator as with aseptic processes, or protect the operator from the product as with potent product handling. The earliest uses of aseptic isolators were for sterility testing. Sterility test isolators make up most of the aseptic isolators in use and are available in many different sizes and configurations. Sterility test isolators do not need to be installed in a classified area. No formal requirement exists for a Grade D environment, but the area should be controlled to allow only trained personnel. The room should also have temperature and humidity control.
Autoclaves (steam sterilizers) used to prepare media for sterility testing were interfaced with isolators to keep the entire sterility test process under isolator conditions. Additional uses for aseptic isolators include component transfers, charging of sterile powders, and interface isolators for filling machines, depyrogenation ovens, and lyophilizers.