Sensitive and selective detection of alcohols via fluorescence modulation

<p>Reported herein is the selective detection of aliphatic alcohols using cyclodextrin-promoted, proximity-induced fluorescence modulation of a high-quantum yield fluorophore. This fluorescence modulation occurred when the analyte was held in close proximity to the fluorophore via non-covalent cyclodextrin–analyte–fluorophore interactions, and led to unique modulation responses for each analyte, fluorophore and cyclodextrin investigated. These changes in fluorescence were used for the generation of an array using linear discriminant analysis that successfully generated unique pattern identifiers for 99% of the investigated analytes, and could detect alcohols at micromolar concentrations. These results represent a fundamentally new detection approach for these challenging analytes, and have significant potential in the development of novel detection schemes.</p

Environmentally friendly procedure for the aqueous oxidation of benzyl alcohols to aldehydes with dibromodimethylhydantoin (DBDMH) and cyclodextrin: Scope and mechanistic insights

<p>Reported herein is an environmentally friendly procedure for the oxidation of benzyl alcohols to aldehydes using an inexpensive, commercially available reagent, 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), and a variety of cyclodextrin additives under fully aqueous solvent conditions. This reaction proceeds with moderate to good yields for a broad scope of benzyl alcohol substrates, with the cyclodextrin acting to enhance the desired reactivity and limit undesired aromatic bromination side products. The reported experiments provide substantial mechanistic insight that will drive further reaction optimization and have broad-reaching applications.</p

Cyclodextrin-Enhanced Extraction and Energy Transfer of Carcinogens in Complex Oil Environments

Reported herein is the use of γ-cyclodextrin for two tandem functions: (a) the extraction of carcinogenic polycyclic aromatic hydrocarbons (PAHs) from oil samples into aqueous solution and (b) the promotion of highly efficient energy transfer from the newly extracted PAHs to a high-quantum-yield fluorophore. The extraction proceeded in moderate to good efficiencies, and the resulting cyclodextrin-promoted energy transfer led to a new, brightly fluorescent signal in aqueous solution. The resulting dual-function system (extraction followed by energy transfer) has significant relevance in the environmental detection and cleanup of oil-spill-related carcinogens

Detection of Organochlorine Pesticides in Contaminated Marine Environments via Cyclodextrin-Promoted Fluorescence Modulation

The development of practical and robust detection methods for pesticides is an important research objective owing to the known toxicity, carcinogenicity, and environmental persistence of these compounds. Pesticides have been found in bodies of water that are located near areas where pesticides are commonly used and easily spread to beaches, lakes, and rivers; affect the species living in those waterways; and harm humans who come into contact with or eat fish from such water. Reported herein is the rapid, sensitive, and selective detection of four organochlorine pesticides in a variety of water sources across the state of Rhode Island using cyclodextrin-promoted fluorescence detection. This method relies on the ability of cyclodextrin to promote analyte-specific fluorescence modulation of a high quantum yield fluorophore when a pesticide is in close proximity, combined with subsequent array-based statistical analyses of the measurable changes in the emission signals. This system operates with high sensitivity (low micromolar detection limits), selectivity (100% differentiation between structurally similar analytes), and general applicability (for different water samples with varying salinity and pH as well as for different water temperatures)

Efficient fluorescence detection of aromatic toxicants and toxicant metabolites in human breast milk

<p>Once chemical contaminants are released into the environment, there are a number of concerns that arise regarding the environmental persistence of the contaminants, their known and suspected toxicities, and their potential disruption to the ecosystem. One class of contaminants that is of continuing concern is polycyclic aromatic hydrocarbons (PAHs), persistent organic pollutants that are significant components of oil spills. PAHs have been found in the breast milk of nursing mothers living in oil spill-affected regions, and can harm the nursing children. We report herein the sensitive and selective detection of 10 PAHs and PAH metabolites in human breast milk using fluorescence energy transfer from the PAH to a high quantum yield fluorophore, and array-based statistical analyses of the resulting fluorescence responses. This detection system was able to separate and identify the PAHs with 100% success in human breast milk and at concentrations as low as 0.17 μM. These results have significant implications in public health and in the monitoring and mitigation of environmental disasters.</p