Apparatus for accelerated temperature cycling

Abstract

An automatic control unit, activating electrically operated solenoid valves, is used to regulate the flow of “hot” and “cold” water from two thermostated baths to the jacket of a reaction vessel so that the temperature of a liquid sample within the vessel follows a highly reproducible programmed cycle. A comparison is made of the temperature hysteresis between 23–33° during a 16 min cycle, when the flow rates to the vessel are changed and when the valves are operated manually. The adjustment of temperature hysteresis to effect the accelerated storage testing of liquid preparations is described.