It can take up to two weeks for colonies to grow enough for detection by the naked eye, and even the most experienced microbiologists will inevitably make counting errors, especially when the CFU counts are high. On the other hand, the Growth Direct™ System uses a proprietary imaging technology that can detect microcolonies of as few as 100 cells. Counts can be completed more quickly without becoming subject to the inconsistencies of manual counting.
People are error-prone. Manual microbial testing opens the door to errors during sample capture, incubation, counting, and recording. In addition, whenever the technician handles the sample there is a potential for contamination. With automatic enumeration, however, the technology only needs to be configured once for the type of assay being performed. Quality control personnel can create the assay parameters for the type of test being performed, and the technology will run methods as indicated.
With manual methods, even perfectly labeled plates can be placed into the wrong incubators or associated with wrong colony counts. The Growth Direct™ System eliminates these errors with a LIMS-integrated barcode system, which allows the machine to track and process each cassette according to its contents. These labels also allow for the upload of data, reducing common errors associated with manual data entry.
Interim counts are often requested by manufacturing to identify potential issues with batches as early as possible, but they drastically increase the potential for human error. With the traditional method, microbiologists must remove plates from incubators, perform colony counts and place the plates back into their correct location. The Growth Direct™ System keeps a count for each sample that is updated on a fixed time interval as samples are imaged. When an interim count is requested by manufacturing, the technician simply needs to look at the Growth Direct™ user interface to see the current count.
Internal studies have shown that as the CFU count on a sample increases, the variance in the number colonies seen by microbiologists also increases. This can be a function of experience, age, and other factors. With automatic methods, CFU counting is performed by the Growth Direct™ System. The imaging technology ensures interim counts will never be mysteriously higher than final totals.
Want to discover more ways Growth Direct can improve your testing processes? Download the free guide, “4 Benefits of Rapid Detection and Enumeration” today.