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Most antianxiety drugs (anxiolytics) work by modulating neurotransmitters in the brain. Benzodiazepines are fast and effective anxiolytic drugs; however, their long-term use is limited by the development of tolerance and withdrawal symptoms. Ligands of the transtocator protein l18 kilodaltons (kD)] may promote the synthesis of endogenous neurosteroids, which also exert anxiolytic effects in animal models. Here, we found that the translocator protein (18 kD) ligand XBD173 enhanced [gamma]-aminobutyric acid-mediated neurotransmission and counteracted induced panic attacks in rodents in the absence of sedation and tolerance development. XBD173 also exerted antipanic activity in humans and, in contrast to benzodiazepines, did not cause sedation or withdrawal symptoms. Thus, translocator protein (18 kD) ligands are promising candidates for fast-acting anxiolytic drugs with less severe side effects than benzodiazepines.

The design of the phosphorescent oxygen nanosensor is described, where two-photon (2P) light harvesting and intramolecular energy transfer (ET) are succeeded by the intersystem crossing within the acceptor chromophore to induce its phosphorescence, which is sensitive to oxygen. Various Pt phorphyrin-coumarin based sensors are synthesized and their characteristics are analyzed to study the proposed design.

Fluorescence quenching in solutions of a pendant-functionalized conjugated polymer chemosensor (ttp-PPETE) is evaluated in the presence of a variety of transition metal cations, including Ni(super 2+), Co(super 2+), Cu(super 2+), Fe(super 2+), and Cr(super 6+) is presented. Photophysical characterization for ttp-PPETE includes absorbance, emission, and single-photon counting lifetimes in the absence and presence of varying concentrations of the analytes.

Research has been conducted on the single-stranded DNA nuclease F factor TraI. The generation of the R150A mutant of F TraI36 has been carried out in analyzing the residues conserved among the proteins and the results indicate that this mutant's relaxase activity is reduced.

A water-soluble triacetic acid cryptophane-A derivative (TAAC) is prepared and determined by isothermal calorimetry and fluorescence quenching assay in order to find out xenon association constant. Tris(triazole propionic acid)cryptophane-A derivative (TTPC) has showed the effect of solvation of the carboxylate anions on the aqueous behavior of the large, nonpolar cryptophane.

A model enhanced two-photon-absorbing (2PA) antenna-triplet core dyads is studied for identifying undesirable photinduced electron transfer (ET) processes and for evaluating their distance dependence. Guidelines are developed for designing the optimized-triplet core 2PA systems for biological applications.

Research examines the protein dynamics, exhibited by the heme pocket of horseradish peroxidase, in a photochemical reaction involving quenching of the excited triplet state of the porphyrin systemby the bound bezohydroxamic acid. Results suggest that solvent modifies the fluctuations in the heme pocket and the fluctuations themselves are a result of long amplitude breathing motions of the protein.