qPCR with quick and easy-to-interpret results will be key
As quantitative Polymerase Chain Reaction (qPCR) becomes more accepted and available to a range of industries looking to quantify their (specific) microbial populations, the ability to provide quick and easy-to-interpret results will be key. The initial development of qPCR assays has been focused on potential human pathogens for use by the medical sector. Now, many manufacturers including LuminUltra, offer assays for use in non-medical, industrial markets to test for known harmful organisms in water systems. If left undetected, those same organisms can create costly problems, including product degradation, infrastructure corrosion, and process inhibition.
Current drawbacks of traditional testing methods
The prevalent testing methods for these industries includes culture via plate counts and bug bottles. These methods have a high degree of specificity and are trusted by technicians and managers. However, there are drawbacks associated with these techniques.
Some drawbacks include;
- only measuring a portion of the total population
- subjective results
- long time-to-results (days to weeks)
There are also organisms, such as methanogens that are not readily culturable and cannot be measured by the prevalent testing methods.
qPCR is a high-tech method for useful insights on your microbial population
qPCR testing involves cycles of heating and cooling that serve to replicate a specific DNA sequence (gene) from a target organism or organisms. As the target DNA sequence is replicated, the amount of a fluorescent tag increases proportionally to the replication of the target DNA sequence. This fluorescence is directly measured in real-time by the qPCR instrument.
The raw data result obtained from a test is known as cycle threshold (Ct). It indicates at what point in the reaction the fluorescence of the target increased above the level of the baseline fluorescence. Combined with a standard curve created by using known concentrations of the target DNA sequence, it is possible to calculate the amount of gene copies present in the original sample, and from the volume of sample processed, a concentration of gene copies/mL (or gene copies per gram or surface area). With this data, operators can better understand which microbes are having the most impact – good or bad – on their system.
The sensitive, objective, rapid, and specific results provided by qPCR testing gives water system operators a powerful new tool to assess and manage risk. For more information, see LuminUltra’s GeneCount® in-field qPCR solutions.