Measuring bacterial contaminants in ultrapure water. A rapid analytical method

The availability of ultrapure water is one of the basic requirements of semiconductor manufacturing. The methods currently used to detect microbial contaminants in UP water can significantly underestimate the actual levels of contamination. This article describes the use of a specialized molecular biology technique known as the polymerase chain reaction that provides rapid and sensitive detection of microbial contaminants. By employing this technique on UP-water samples collected over an 11-month period, we demonstrated that microbial contamination was episodic in nature and that 44.1% of the samples tested showed a positive indication of bacterial contamination of at least 1 CFU/L. The attractive features of this technique are its sensitivity, cost-effectiveness, and speed of detection.