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Reference measurement procedure to determine virus concentration


The concentration of pathogenic microorganisms is an important parameter when medical decisions need to be made. the number of microorganisms (e.g. viruses or bacteria) can be determined by counting certain genetic sequences in a sample. The digital polymerase chain reaction (dPCR) is a method that is perfectly suited to counting these genetic sequences directly and to measuring concentration in a metrologically traceable way.

Digital PCR requires a large number of reaction chambers that are all of the same size. Droplet-based dPCR uses a water-in-oil emulsion that is generated in microfluidic structures.

Such measurement procedures used to count biological objects are therefore considered as key technologies to establish traceability to the SI system of units. Potential applications range from medicine to broad areas of biology and on to environmental as well as nutritional issues.

Within the scope of the AntiMicroResist project, different measurement procedures for iden and quantifying bacterial and viral pathogens were investigated with the support of EMPIR, the European metrology program. This project aimed to investigate new materials and methods to detect, monitor and assess antimicrobial resistance. Reference measurement procedures to quantify virus concentration based on dPCR open up new possibilities for the external quality assurance of medical laboratories. These procedures have the potential to replace the methods based on consensus values that are currently used. The possibility of using dPCR for the quantitative detection of HIV-1 and CMV (cytomegalovirus) was demonstrated successfully for the first time within the scope of interlaboratory compariso