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Silver clusters were incorporated into the Y zeolite framework and used as a photocatalyst toward pirimicarb. X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), and low-temperature steady-state photoluminescence spectroscopic data indicate the formation of metallic silver as well as ionic clusters. The photodecomposition of the pirimicarb pesticide is enhanced in the presence of silver doped into zeolite Y; where the observed rate constant in the presence of the catalyst is 2.2 × 10 –2 min –1 compared to the rate constant of 7.0 × 10 –4 min –1 for the uncatalysed irradiated pirimicarb solution. GC-MS indicates that while pirimicarb alone was hydrolysed into N-N-dimethylcarbamic acid and 2-dimethylamino-5,6-dimethylpyrimidin-4-ol; the presence of AgY catalyst produced the selective oxidation product 4-dimethylcarbamoyloxy-5,6-dimethylpyrimidin-2-yl-carbimic acid.

This study investigated the synthesis and catalytic properties of silver, platinum, and mixed Ag-Pt dopants into the 5A zeolite host. The prepared materials were tested toward the photodecomposition of the pesticide naptalam.  The results indicate strong catalytic activities for the Ag-Pt-5A catalyst whereas, the Ag5A was found out to be the only doped zeolite that adsorbs the pesticide as soon as it came in contact with its surface. a-naphtylamine and phthalic acid were determined to be major photodecomposition products.

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Neutron reflectometry has been used to study the self-assembly of a membrane protein, OmpF, onto a gold-coated silicon substrate from solution. OmpF associates into trimers and has been modified so that each trimer binds to the gold substrate through cysteine residues. Quantitative analysis of the data revealed that 12% of the surface was covered by the oriented protein with 27600 water molecules surrounding each trimer.

Several synthetic approaches have been used to obtain nano-sized monoclinic WO₃ (m-WO₃) powders. All of these methods begin with a standard preparative method where H₂WO₄ is first generated by passing a Na₂WO₄ solution through a cation-exchange resin. It is shown that high surface area particles are produced by dripping the H₂WO₄ exiting from the ion-exchange column into a solution containing oxalate and acetate exchange ligands or alternatively, into a water-in-oil (w/o) based emulsion. In comparison to commercial WO₃ powders, the surface area of the m-WO₃ powders were higher by factors of 10 and 20 times when prepared in the presence of acetate/oxalate chelating agents and w/o emulsions, respectively. The much higher surface areas enable infrared spectroscopic identification of surface sites along with detection and monitoring of gaseous reactions and adsorbed species on the surface of this metal oxide. This is demonstrated with the adsorption of a nerve agent simulant, dimethyl methyl phosphonate. In general, little is known about the reactions of gaseous molecules on m-WO₃ surfaces and the fabrication of high surface area m-WO₃ particles will aid in gaining an understanding of the chemical processes occurring in WO₃ based sensors.

The photoluminescence spectra of dicyanoargenate(I) ions doped in KCl host crystals show several ultraviolet and visible emission bands. Each emission band becomes dominant at a characteristic excitation wavelength; i.e. the energy of the emission can be tuned. Both the experimental and theoretical results suggest the formation of Ag–Ag bonded excimers and exciplexes between adjacent Ag(CN)2−ions in the host lattice. The experimental evidence includes the broadness, the absence of detailed structure, and the low band energies of the luminescent bands. Ab-initio and extended Hückel calculations show that the lowest unoccupied molecular orbital (LUMO) is bonding with respect to Ag–Ag bonds while the highest occupied molecular orbital (HOMO) is antibonding. Further, the calculations indicate the existence of exciplexes with shorter Ag–Ag bond distances, higher binding energies, and larger Ag–Ag overlap populations than the corresponding ground state oligomers. The results in this study give rise to a new optical phenomenon which is called ‘exciplex tuning’. Tuning of the emission over the 285–610 nm wavelength range has been achieved in KCl/Ag(CN)2−crystals by site-selective excitation and varying the Ag(CN)2−dopant concentration.

Nitric oxide-containing drugs present a critical remedy for cardiovascular diseases. Nitroglycerin (NG, O–NO) and S-nitrosoglutathione (SNG, S–NO) are the most common nitric oxide drugs for cardiovascular diseases. Insights regarding the binding affinity of NO drugs with lysozyme and human serum albumin (HSA) proteins and their dissociation mechanism will provide inquisitive information regarding the potential of the proteins as drug carriers. For the first time, the binding interactions and affinities are investigated using molecular docking, conventional molecular dynamics, steered molecular dynamics, and umbrella sampling to explore the ability of both proteins to act as nitric oxide drug carriers. The molecular dynamics simulation results showed higher stability of lysozyme–drug complexes compared to HSA. For lysozyme, cardiovascular drugs were bound in the protein cavity mainly by the electrostatic and hydrogen bond interactions with residues ASP53, GLN58, ILE59, ARG62, TRP64, ASP102, and TRP109. For HSA, key binding residues were ARG410, TYR411, LYS414, ARG485, GLU450, ARG486, and SER489. The free energy profiles produced from umbrella sampling also suggest that lysozyme–drug complexes had better binding affinity than HSA–drug. Binding characteristics of nitric oxide-containing drugs NG and SNG to lysozyme and HSA proteins were studied using fluorescence and UV–vis absorption spectroscopy. The relative change in the fluorescence intensity as a function of drug concentrations was analyzed using Stern–Volmer calculations. This was also confirmed by the change in the UV–vis spectra. Fluorescence quenching results of both proteins with the drugs, based on the binding constant values, demonstrated significantly weak binding affinity to NG and strong binding affinity to SNG. Both computational and experimental studies provided important data for understanding protein–drug interactions and will aid in developing potential drug carrier systems in cardiovascular diseases.

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