A novel membrane contactor method was used to produce size-controlled poly(ethylene glycol)-b-polycaprolactone (PEG-PCL) copolymer micelles composed of diblock copolymers with different average molecular weights, Mn (9200 or 10,400 Da) and hydrophilic fractions, f (0.67 or 0.59). By injecting 570 L m(-2) h(-1) of the organic phase (a 1 mg mL(-1) solution of PEG-PCL in tetrahydrofuran) through a...

Micelles play an important role in both experimental and computational studies of the effect of lipid interactions on biological systems. The spherical geometry and the dynamical behavior of micelles makes generating micelle structures for use in molecular simulations challenging. An easy tool for generating simulation-ready micelle models, covering a broad range of lipids, is highly desirable....

In this study, a novel adamantanamine-paclitaxel (AD-PTX) incorporated oligochitosan- carboxymethyl-β-cyclodextrin (CSO-g-CM-β-CD) self-assembly macromolecular (CSO-g-CM-β-CD@AD-PTX) micelle was successfully prepared in water through sonication. The formed molecules were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance (NMR) spectroscopy, two-dimension...

We have performed atomistic molecular dynamics simulations of an anionic sodium dodecyl sulfate (SDS) micelle and a nonionic poly(ethylene oxide) (PEO) polymer in aqueous solution. The micelle consisted of 60 surfactant molecules, and the polymer chain lengths varied from 20 to 40 monomers. The force field parameters for PEO were adjusted by using 1,2-dimethoxymethane (DME) as a model compound ...

Melittin is a cationic hemolytic peptide composed of 26 amino acid residues. It is intrinsically fluorescent because of the presence of a single tryptophan residue which has been shown to be crucial for its hemolytic activity. We have previously shown that the sole tryptophan of melittin is located in a motionally restricted region in the membrane and the tryptophan environment is modulated in ...

The ability to control the micelle size of poly(lactic acid) and poly(ethylene glycol) (PLA–PEG) block copolymers is important for controlling their circulation in blood cell recognition, drug release and therapeutic effects. We successfully controlled the micelle size by changing the block number of copolymers (multiblock index). PLA–PEG multiblock copolymers with multiblock indexes ranging fr...

Efficient formulations used in hydrometallurgy are often based on synergistic action of two oil-soluble extractants at an optimized mole fraction. In this series papers, we describe the N,N’-dimethyl-N,N’-dioctylhexylethoxymalonamide (DMDOHEMA)/di(2-ethylexyl) phosphoric acid (HDEHP) system, and how expression effect varies with acidity, using three common representations: distribution ratios, ...

Equilibrium and nonequilibrium distributions of molecular aggregates in a solution of a nonionic surfactant are investigated at the total surfactant concentration above the second critical micelle concentration (CMC2). The investigation is not limited by the choice of a specific micellar model. Expressions for the direct and reverse fluxes of molecular aggregates over the potential humps of the...

To determine the relative importance of the confining geometry and nanoscopic length scale versus water/interface interactions, the dynamic interactions between water and interfaces are studied with ultrafast infrared spectroscopy. Aerosol OT (AOT) is a surfactant that can form two-dimensional lamellar structures with known water layer thickness as well as well-defined monodispersed spherical r...

Photophysical processes of ethidium bromide (EB) in homogeneous solutions, micelles, and reverse micelles have been investigated. In acetonitrile, the fluorescence intensity and lifetime of EB are 6.3 ( 0.3 times those in water and 1.25 ( 0.1 times those in acetone. This is attributed to the weaker hydrogen-bond acceptor property of acetonitrile, compared to water and acetone. Addition of water...