HMR evaluation confirms suitability of ChemScan RDI for rapid, routine microbiology testing

The suitability of using the ChemScan® RDI for rapid, routine microbiological testing of water in the pharmaceutical industry has been reinforced by a recent evaluation conducted by Hoechst Marion Roussel AG, and published in PDA Journal of Pharmaceutical Science & Technology¹.

The evaluation confirmed that the sensitivity of the ChemScan RDI solid phase cytometer was at least equivalent to that of the standard plate method. In addition, it showed that where higher counts were detected by the new system, these could clearly be attributed to cells which were viable but unable to form visible colonies when cultivated using standard high nutrient media incubated for 2-4 days. However, colony numbers on R2A agar, a low-nutrient medium developed specifically to improve recovery of bacteria from water, were almost as high, after ten days, as the 2-hour ChemScan counts.

The authors acknowledge that cultivation-based methods are generally prone to underestimate the true number of viable micro-organisms in water samples, and that revised microbial limits should be considered for the ChemScan RDI in view of its greater sensitivity and accuracy.

Trends for both the plate and ChemScan RDI methods were parallel.

When contamination problems were identified, the greater speed to result of the ChemScan RDI - which produces data within 90 minutes of sampling and requires no cultivation stage - enabled the efficacy of corrective action to be confirmed virtually immediately. By plate methods, this could take anything from two to five days.

In conclusion, the authors indicate that the greater speed of the ChemScan RDI will allow better contamination control because microbiological excursions can be detected much earlier and corrective actions taken more promptly. Furthermore, additional testing will allow the source of the problem to be quickly identified and the efficacy of remedial action to be checked immediately.

Issued on behalf of Chemunex by HCC.De Facto Consultants.
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Editors Note:
Chemunex, a biotechnology company listed on both EASDAQ and Euro NM, is a leader in the development and distribution of highly sensitive and rapid testing systems for the detection of microbial contamination in a variety of industrial and consumers products, including pharmaceuticals, drinking water, cosmetics, foods and beverages. The innovative technology developed by the Company over the last five years brings new standards of quality to the industrial microbiology testing business.

This technology includes the ChemScan RDI which has been recognised by a number of awards, including the Queen's Award for Technology, as well as recently securing a place in the Millennium Dome as a Millennium Product.

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