An alternative clean-up column for the determination of polychlorinated biphenyls in solid matrices

Abstract

The need for continuous monitoring of polychlorinated biphenyls (PCBs) has necessitated the development of analytical techniques that are sensitive and selective with minimal reagent requirement. In light of this, we developed a column for clean-up of soil and sediment extracts, which is less demanding in terms of the amount of solvent and sorbent. The dual-layer column consists of acidified silica gel and molecularly imprinted polymers (MIPs). MIPs were synthesized via aqueous suspension polymerization using PCB 15 as the dummy template, 4-vinylpyridine as the functional monomer and ethylene glycol dimethacrylate as the cross-linker and the obtained particles characterized via SEM, BET, and batch rebinding assays. Pre-concentration of the spiked real-world water sample using MISPE gave recoveries between 85.2 and 104.4% (RSD < 8.69). On the other hand, the specific dual-layer column designed for clean-up of extracts from complex matrices provided recoveries of 91.6-102.5% (RSD < 4%) for spiked soil, which was comparable to clean-up using acidified silica (70.4-90.5%; RSD < 3.72%) and sulfoxide modified silica (89.7-103.0%; RSD < 13.0%). However, the polymers were reusable maintaining recoveries of 79.8-111.8% after 30 cycles of regeneration and re-use, thereby availing a cost-effective clean-up procedure for continuous monitoring of PCBs. Method detection limits were 0.01-0.08 ng g(-1) and 0.002-0.01 ng mL(-1) for solid matrices and water, respectively.

Molecularly imprinted polymers—A closer look at the control polymer used in determining the imprinting effect: A mini review

“…Synthesis of MIPs has been achieved following several synthetic strategies that range from the traditional bulk polymerization 21 to other new strategies that include precipitation polymerization, 22 suspension polymerization, 23 emulsion polymerization, 24 surface polymerization 25 . Except bulk polymerization, which results into polymer monoliths that require grinding to obtain smaller particles, all other strategies provide polymeric beads that are ready for different analytical applications.…”

Towards miniaturized electrochemical sensors for monitoring of polychlorinated biphenyls

“…Once in the environment, PCBs are transported over long distances owing to their long range transport property where they bind strongly to soil and sediment that act as secondary sources of PCBs through volatilizations 7 . Polychlorinated biphenyls have been reported in various environmental media ranging from indoor air 8 , 9 , water and sediment 10 , 11 and soil 12 . Of great concern is that these chemicals enter into the food chain where human beings are exposed mainly through the diet and breathing contaminated air, having been detected in human tissue including blood 13 , adipose tissue 14 , liver and kidney 15 .…”