Even when using the time-tested traditional method for colony enumeration, microbiologists often run into difficulties when working with unusual samples. Creams and cosmetic products, for example, are often hard-to-filter and cell cultures and tissue samples contain filter-clogging materials.
There are many ways for quality control personnel to filter out the materials in these samples, allowing them to efficiently run traditional filtration tests. Previously, we covered the following fixes:
- Solubilization: The addition of mild detergents can solubilize particulates while leaving bacterial cells intact, allowing for filtration through standard filters.
- Enzymatic Treatments: Certain enzyme treatments can dissolve mammalian cells and protein by-products while leaving bacterial cells intact. The sample can then be filtered using traditional methods.
- Tissue Growth: When working with harvested tissue samples, microbiologists can incubate the sample in liquid growth media. If present contaminating microbes will grow out from those tissues into the liquid growth media, from which they can then be filtered, plated and incubated.
The Benefits of Growth-based RMM
These techniques provide a way to perform standard filtration testing. Beyond the benefits of larger samples and reduced limits of detection, these processes open the opportunity to leverage a wider range of automated, growth based RMM technologies, since many automated growth-based RMMs leverage the same preparation steps as the compendial method. The benefits of combining unusual sample solutions with automated enumeration and reporting include:
- Faster Results: Equipped with charged-coupled device (CCD) imaging technology, the Growth DirectTM System can detect colony-forming units of roughly 100 cells –too small to be seen by the naked eye. Users can therefore obtain colony counts in about half the time of the compendial method, even when working with samples that require more advanced filtration techniques
- High Reliability: Once users have prepared and labeled their samples, the equipment automates the rest of the enumeration and reporting process.
- Labor Efficiency: Once samples are prepared, the automated rapid method takes over to perform incubation, enumeration and reporting, allowing microbiologists time to work on other high value activities.
- Reduced Times-to-Market: Faster testing ultimately means faster times to market for products awaiting shipment. The Growth DirectTM System can typically produce reliable results in about half the time of the traditional methods, allowing manufacturers to ship their products sooner.
Are you ready to ramp up productivity with your unusual samples? Find out more about the benefits of growth-based RMM by reading our free guide.