As any Quality Control professional will tell you, the key to any accurate laboratory practice is ensuring that your reagents are at optimal levels of purity to ensure their accuracy and consistency. However, this can be challenging, especially when biological samples such as serum, tissue homogenates, plasma, etc., are concerned. One of the most troublesome aspects facing laboratories is the ‘Matrix Effect.’
Determining the Matrix Effect
The ‘Matrix Effect’ takes place when components of biological samples such as proteins, phospholipids, carbohydrates, and so on interfere with the quantification of analytes. To find out whether or not this phenomenon is influencing your results, you will need to carry out a spike and recovery assay and evaluate the values you obtain.
If your recovery from the assay falls below 80 percent, then you will have a Matrix bias problem on your hands. Ideally, your results should fall somewhere between 80 percent and 120 percent.
While low readings may be taken as an indicator of erroneous results caused by the Matrix Effect, this is not a perfectly reliable method. This is because low readings might result from low analyte concentrations, insufficient incubation times, and so on.
Overcoming the Matrix Effect
Figuring out whether your results are being influenced by the Matrix Effect is only the first step. One way to overcome the effect is to dilute your samples. When dealing with biological samples such as plasma and serum, it’s prudent to use the same buffer you used while diluting your recombinant standards. You will need to be careful that you take this dilution into account when analyzing your data.
Should you need to dilute your samples even further to fully overcome the effect, you should ensure that you dilute your standards to the same level so that their matrix effects interference are maintained at the same level.
Final Thoughts
The Matrix Effect is a major culprit when it comes to biases in laboratory results, potentially costing inestimable losses. While diluting your samples with the appropriate diluent is an effective way of dealing with the problem, the quality of your diluent may still result in inaccuracies in your results. For the best results, insist on 100% Human matrices when handling biological samples.
At UTAK, we provide the highest quality clinical, forensic, and environmental toxicology quality control products to laboratories all over the world and will be honored to help you achieve excellence in your analytical efforts. Connect with a Control Freak to see how we can help you take control of your testing.