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Teratogenic, carcinogenic, and pervasive endocrine disrupting compounds (EDCs) in suspect water systems present an immediate threat to both the environment and potable water supplies. The US Environmental Protection Agency mandated research regarding suspect EDCs, personal care products, and pesticide pollution requires the use of suitable methods of analysis that can perform extraordinarily well in the field and show low "cost to benefit" ratios. Such methods must increasingly address the need for enhanced sensitivity and selectivity in interrogating complex mixtures. Here, several device and method optimization strategies, specific for these classes of compounds, are discussed and include, among others, the preconcentration of field samples utilizing high performance extraction disk cartridges. Matrix interferences and undetectable concentration levels are eliminated by the way of an RP extraction technique that is vital to obtaining detectable concentrations of target analytes in the ppb range. Established capillary EKC methods are modified and implemented on a short capillary for low nanoliter discrete injections, efficient separations, and detection with LIF of analyte mixtures. Efficient separations were achieved with plate counts ranging from 10(3) to 10(4). Analytes spiked into real sample matrices at ppb levels were easily separated and detected via LIF using a He/Cd laser operating at 325 nm. The presented techniques are valuable in determining both the presence and concentration of suspect contaminates in different water systems. The methods presented here could easily be extended to microfluidic platforms with little to no optimization for on-site testing. |
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