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A study was conducted to demonstrate the feasibility of immobilizing a bilayer-forming surfactant onto an ion-exchange resin with retention of gel to liquid-crystalline phase transition behavior. The results confirmed the retention of a gel to liquid-crystalline phase transition of the surfactant occurring between 296 and 318 K.

The selectivity of electrochemical nitric oxide (NO) reduction by heme-didodecyldimethylammonium bromide (DDAB) and myoglobin-DDAB films as a function of potential and pH are examined. The selectivity of the pathway depends on whether a proton or NO molecule is transferred to a Fe(super II)-NO(super -) reaction intermediate and is influenced by pH, NO concentration and potential.

The interaction of the positively charged surfactant DDAB (didodecyldimethyl ammonium bromide) with preformed vesicles from POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine), and negatively charged surfactant oleate, are investigated. In both cases the matrix effect are shown by DDAB with the formation of mixed vesicles of size distribution depending on reactant concentrations.

It has been demonstrated that Michael addition of metal ketone enolate to alpha, beta-unsaturated esters successfully proceeds using tin enolate combined with Bu4NBr-catalyst. An ab initio calculation for the reaction system clarified the details of the reaction course.

Core-shell structured dual-mesoporous silica spheres (DMSS) possessing smaller pores in the shell and larger tunable pores in the core are prepared by using an amphiphilic block copolymer (polystyrene-b-poly (acrylic acid), PS-b-PAA) and cetyl trimethyl ammonium bromide (CTAB) as cotemplates. Drug storage and release testing results have shown that the diffusing rate of the stored drug is controlled by changing the shell thickness of DMSS.

The structure of a DNA-dimethyldidodecylammonium bromide (DDAB) film is described to undergo a transition in response to the water content in the surrounding environment. The structure of DNA in the film has depended on the water content and temperature of the environment, while the state of DDAB has depended essentially only on the water content.

A newly developed size control method is described for thiol-protected colloidal gold nanoparticles (Au NPs) under mild conditions in the presence of quaternary ammonium salt and proton acid at room temperature. The mild reactivity of the acids and bromide ions to organic ligands has facilitated the use of various thiols sensitive to heat, base, and reducing agents.

Ellipsometry was used to study the wetting of water by hexadecane as a function of the concentration of the cationic surfactant dodecyltrimethylammonium bromide (DTAB) in the aqueous phase and temperature. The results data support the interpretation of the L-S phase transition as the wetting of a liquid-like mixed monolayer of surfactant + alkane by a surface frozen layer of hexadecane.

A simple solution route is developed to hydrogen terminated silicon nanoparticles. Macroscopic amounts of powder can be obtained of either crystalline or amorphous nanoparticles, depending upon solvent and reaction conditions like temperature less than 300 degree Celsius.