Cyclodexrtrins as hosts for the array-based detection of persistent organic pollutants in complex media
The ability to quickly determine the nature of small-molecule toxicants after an anthropogenic event would greatly benefit first responders and medical personnel. Current detection methods, while elegant, require several separation and purification steps before the samples can be submitted for analysis, which can be a time-consuming process. There is a crucial knowledge gap that exists as a result. Reported herein is the use of a non-toxic, commercially-available molecule, cyclodextrin, to rapidly isolate and detect the toxic components involved in a spill event that would address this knowledge gap. This cyclodextrin-based scheme would work as a compliment to established analysis procedures by establishing a rapid, high-throughput procedure that can be used to quickly scan samples to determine the nature of the compounds involved in a spill event. This would provide first responders with the information they need to develop an effective response in a timely manner, and samples would still be sent for more intense analysis using standardized procedures, such as those set by the Environmental Protection Agency (EPA) to confirm the results and quantify them. Similarly, this method can be used by medical personnel to quickly analyze samples from patients to determine if their symptoms are a result of a spill event. Cyclodextrins enable the identification of toxicants proximity-induced interactions between a toxicant and high-quantum yield fluorophore. Cyclodextrins have hydrophobic cores and hydrophilic surfaces, and both the toxicant and fluorophore use the cyclodextrin as a scaffold, forcing them in close proximity to one another. Once the toxicant and fluorophore are closely associated, gamma-cyclodextrin, the primary cyclodextrin derivative of interest in this work, facilitates proximity-induced energy transfer from the toxicant donor to the fluorophore acceptor. Energy transfer to and emission from the fluorophore occurs upon excitation of the toxicant, and the resulting emission spectra is unique to each fluorophore-toxicant combination. These unique signals can lead to the array-based detection of the toxicant as they act as photophysical “fingerprints” for the toxicant. The cyclodextrin-based scheme discussed herein offers a number of operational advantages. First, this scheme is well-suited for high-throughput screening as fluorescence measurements are fast to obtain and samples require little pretreatment before analysis (usually a simple dilution is all that is needed). Second, detection occurs successfully in multiple complex matrices, including seawater, oiled samples, and human plasma, breast milk, and urine. As such, this method can be useful to a variety of spill scenarios, and assist medical personnel. Third, cyclodextrins can effectively remove some of the most toxic components from oil spills, helping to solve many oil-spill related problems and enabling a tandem extraction-detection system. Taken together, this work has significant applications for public health, environmental remediation, and disaster response and relief.
Chemistry|Analytical chemistry|Organic chemistry
Nicole Cook Serio,
"Cyclodexrtrins as hosts for the array-based detection of persistent organic pollutants in complex media"
Dissertations and Master's Theses (Campus Access).