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How to Deal with the Challenges Pertinent to Perfluorinated...
Perfluorinated compounds (PFCs) compose a family of molecules, which is formulated of varying lengths of fluorocarbons chains with a functional group, like a carboxylic or sulfonic acid, attached.
FREMONT, CA: PFC has been used for over 50 years in numerous products, like firefighting foams, surfactants, and hydrophobic and nonstick coatings. These compounds are specifically resistant to degradation and tend to accumulate in organisms and the ecosystem. Due to their potential disadvantageous effects on human health PFCs have been the subject of increased scrutiny. These compounds move into crops and livestock from contaminated water sources and soil. They are even found in food packaging. Analyzing PFC in a lab can be a complex process; they are in abundance in a lab setting because of their presence in laboratory equipment, which makes them an effortless source of analytical contamination. They can even be absorbed onto surfaces. For achieving an accurate analysis, few precautions must be considered while preparing protocol and execution.
Controlling Background Contamination from Devices
High-performance liquid chromatography (HPLC) components generally have PTFE parts and tubing, and combining this with possible trace levels of PFCs in solvents can influence the analysis of samples with low PFC concentrations. The PFCs released from HPCL components create higher background interference by building on top of the chromatographic column. There are primarily two solutions available to decrease such interference. The first is to use PFC-free solvents in place of the PTFE parts and perfluorinated tubing. The second is to install a delay column between the injector and the LC pump.
Significance of Defining the Appropriate Protocol, Equipment, and Supply
According to a few articles using high-density polypropylene or standard polypropylene for sampling and nitrile gloves is recommended, which then should be replaced frequently to avoid contamination. Items like glass should be avoided for storing PFCs as it absorbs onto glass surfaces, and even nonstick or hydrophobic coatings must not be used as it might contain PFCs.
New analytical devices are efficient in detecting PFCs, and that might help to inject directly for trace analysis. Yet, with a lot of care also contamination might occur during sample processing, even with the chances of the contamination issues to increase with lower PFC concentrations in a sample. There are added problems as well, such as many samples are dirty for direct injection, and purification techniques have to be used.