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Study of electron transfer in ionic liquids is of interest for what it may reveal about the effects of solvent dynamics on electron transfer as well as for helping to inform current efforts to employ ionic liquids as electrolytes in energy-related applications. The present report describes time-resolved fluorescence quenching measurements of electron transfer between electronically excited 7-aminocoumarin dyes and a redox-active pyridinium ionic liquid, 1-butylpyridinium bis(trifluoromethylsulfonyl)imide ([Py4][Tf2N]). Comparable measurements of fluorescence quenching in conventional dipolar solvents were made over 20 years ago, primarily in aromatic amine liquids. Like these prior experiments, use of commercially available coumarin dyes allowed the driving force for electron transfer (-ΔGET) to be varied over a 0.7 V range, leading to electron transfer rates that increase with driving force over the range 1010-1012 s-1. These rates are similar to rates previously measured in aromatic amine solvents, despite the much greater polarity of the ionic liquid, which increases the driving force by more than 0.5 eV. Fluorescence decays of most of the fluorophores in [Py4][Tf2N] were found to be highly non-exponential functions of time, including both subpicosecond components and components in the 102-103 ps range. Such broadly distributed emission dynamics were not observed in prior studies. Emission decays in [Py4][Tf2N] resemble the broadly distributed solvation response characteristic of ionic liquids, suggesting that solvent motions may control the rate of electron transfer, at least in the more slowly reacting dyes. This similarity could be interpreted either in terms of solvent motions being responsible for varying the energy gap or the electronic coupling between the reactant and product states.Herein, we report a dual dye competitive screening method for the identification of five boronic acid functionalized synthetic lectins (SLs) that are selective for prostate-associated targets with the goal of detecting and staging prostate cancer. This method uses differently labeled normal (RWEP-1) and diseased (PC3) cell membrane extracts in a competitive binding assay to identify SLs that bind either the cancerous or normal extracts but not both. Subsequent studies examined the efficacy of these new SL hits in an array format to discriminate six prostate cell lines. The SL array was able to (a) classify the prostate cell lines with 83% accuracy, (b) discriminate the same cell lines based on their metastatic potential (noncancerous/healthy, cancerous/lowly metastatic, and cancerous/metastatic) with 96% classification accuracy, and (c) exhibit enhanced selectivity for prostate-derived versus colon-derived cell lines. see more Further analysis delineated the contribution from each SL in these studies, providing a focused SL array having potential utility as a cancer diagnostic.Mostly, surface-enhanced Raman scattering (SERS) sensors used the Raman characteristic bands concentrated in the Raman “fingerprint” region (500-1800 cm-1), which may result in spectral overlapping interference. The study of the response in the Raman-silent region (10-500 and 1800-2800 cm-1) can help overcome this problem. Hydrogen sulfide (H2S) gas causes a great threat to human’s health, but its low concentration in the airborne species is a challenge for sensitive and selective detection. Herein, a novel low-wavenumber (10-500 cm-1) SERS sensor for H2S gas detection has been developed based on gold nano-bipyramids (Au NBPs) encapsulated by zeolitic imidazolate framework-8 (ZIF-8) (Au NBPs@ZIF-8). The sensor takes advantage of the high adsorption capacity of ZIF-8 toward H2S gas and the H2S-triggered SERS spectral changes in the low-wavenumber Raman-silent region. A clear SERS peak of Au-Br at ∼175 cm-1 generated from Au NBPs@ZIF-8 showed a decrease in the presence of H2S because of the competition of adsorption sites between Au-S and Au-Br bonds. Furthermore, Au NBPs@ZIF-8 can enrich and monitor the level of H2S gas with high efficiency and low interference. The developed sensor has a detection range of 0.2 nM to 20 mM with a limit of detection (LOD) of 0.17 nM. The developed sensor had been applied to detect the H2S gas released from the spoiled fish meat with high selectivity.Dendrimers, notable for their well-defined radial structures with numerous terminal functionalities, hold great promise for biomedical applications such as drug delivery, diagnostics, and therapeutics. However, their translation into clinical use has been greatly impeded by their challenging stepwise synthesis and difficult purification.To circumvent these obstacles, we have pioneered a self-assembly approach to constructing noncovalent supramolecular dendrimers using small amphiphilic dendrimer building units which can be easily synthesized and purified. By virtue of their amphipathic nature, the small amphiphilic dendrimers are able to self-assemble and generate large supramolecular dendrimers via noncovalent weak interactions such as van der Waals forces, H bonds, and electrostatic interactions. The so-created noncovalent dendrimers can mimic covalent dendrimers not only in terms of the radial structural feature emanating from a central core but also in their capacity to deliver drugs and imaging agents folecular PAMAM dendrimers for biomedical applications. Specifically, we start with the introduction of dendrimers and their synthesis, focusing on the innovative self-assembly synthesis of supramolecular dendrimers. We then detail the representative examples of the noncovalent supramolecular PAMAM dendrimers established in our group for the delivery of anticancer drugs, nucleic acid therapeutics, and imaging agents, either within the dendrimer interior or at the dendrimer terminals on the surface. Some of the supramolecular dendrimer nanosystems exhibit outstanding performance, excelling the corresponding clinical anticancer therapeutics and imaging agents. This self-assembly approach to creating supramolecular dendrimers is completely novel in concept yet easy to implement in practice, offering a fresh perspective for exploiting the advantageous features of dendrimers in biomedical applications.