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Reported herein is a multidisciplinary laboratory experiment for advanced undergraduate students that includes elements of material synthesis, in the synthesis of cyclodextrin-containing metal-organic frameworks (CD-MOFs), and environmental chemistry, in the use of these MOFs for pollutant removal. This multiday laboratory experiment starts with the synthesis of cyclodextrin-containing metal-organic frameworks (CD-MOFs) using vapor diffusion crystal growth procedures, followed by the use of the CD-MOFs for a pollutant removal application. Specifically, the CD-MOFs were used for the removal of a methylene blue dye (a common mimic of aromatic pollutants) from an organic solution, with the monitoring of the success of the removal procedures using UV-vis spectroscopy. This experiment was implemented as part of a larger multiday unit, and undergraduate students were particularly engaged with and excited by the CD-MOF synthesis and methylene blue removal experimental modules. As a result, the decision was made to make these two components a stand-alone multidisciplinary laboratory experiment, the results of which are reported herein.

Reported herein is the design, implementation, and evaluation of a full-day outreach program for high school girls that focuses entirely on sugar-related activities. The program, which we ran in February 2016 and February 2017, included multiple hands-on sugar-based experiments to increase the participants' interest in and enthusiasm for science. The success of the program was quantitatively evaluated through the administration of precamp and postcamp surveys. Overall, the survey results indicated a statistically significant improvement in responses in one of the two program years, which corresponds to success in changing the participants' attitudes regarding the practical applicability of science and in increasing their interest in pursuing scientific careers.

The detection of phthalates in human biologic fluids remains an important research objective because it provides an important measure of an individual's exposure to this class of compounds, which have known deleterious health effects. Moreover, the ability to accomplish such detection in fluids that are easy to collect, such as saliva and urine, provides additional practical advantages. Reported herein is the application of cyclodextrin-promoted fluorescence energy transfer and fluorescence modulation to accomplish precisely such detection: the development of sensitive and selective florescence-based detection methods for phthalates in saliva, an easily collectable human biologic fluid. Such saliva-based detection methods occur with high levels of selectivity (100% differentiation) and sensitivity (limits of detection as low as 0.089 µM), and provide significant potential in the development of practical phthalate detection devices. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We have previously developed a highly efficient fluorescence-based toxicant-detection method that operates in complex environments to detect aromatic toxicants and toxicant metabolites with high sensitivity and selectivity. This method relies on the ability of δ-cyclodextrin to act as a supramolecular scaffold, and uses a variety of non-covalent interactions between the cyclodextrin, toxicant, and fluorophore to enable efficient detection. Reported herein is an investigation of the effect of various experimental parameters, including host concentration, temperature, pH, salt, and solvent, on the observed energy-transfer efficiencies. These results advance our understanding of δ-cyclodextrin-based association complexes and provide crucial information for the development of fluorescence-based sensors using such complexation and the resultant fluorescence-based detection. [ABSTRACT FROM AUTHOR]

Reported herein is the sensitive and selective cyclodextrin-promoted fluorescence detection of benzene, toluene, ethylbenzene, xylene, and cumene (BTEXC) fuel components in contaminated snow samples collected from several locations in the state of Rhode Island. This detection method uses cyclodextrin as a supramolecular scaffold to promote analyte-specific, proximity-induced fluorescence modulation of a high-quantum-yield fluorophore, which leads to unique fluorescence responses for each cyclodextrin-analyte-fluorophore combination investigated and enables unique pattern identifiers for each analyte using linear discriminant analysis (LDA). This detection method operates with high levels of sensitivity (sub-micromolar detection limits), selectivity (100% differentiation between structurally similar compounds, such as ortho-, meta-, and para-xylene isomers), and broad applicability (for different snow samples with varying chemical composition, pH, and electrical conductivity). The high selectivity, sensitivity, and broad applicability of this method indicate significant potential in the development of practical detection devices for aromatic toxicants in complex environments. [ABSTRACT FROM AUTHOR]