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A microfluidic approach is described for generating capsules of biopolymer hydrogels at room temperature and with good control of particle size distribution and internal structure. The time of gelation and/or the concentration of the cross-linking agent in the continuous phase are controlled in order to achieve control over the internal structure of biomicrogels from capsules to gradient microgels to microgels with a uniform structure.

A method to measure charge within a molecular circuit that shows negative differential resistance by conducting probe atomic force microscopy is presented. It is observed that the voltage region over which conduction was enhanced correlated strongly with the region over which the scanning probe tip experienced capacitive attraction to the surface.

The impact of the polymer-solvent interfacial free energy on the collapse of the polystyrene chain in water, as well as the aqueous solutions is determined. The change in the free energy is shown to be directly related to the force of the collapsed polymer in a bad solvent.

An evaluation of absolute rate models for electron transfer was undertaken, but the comparison is only limited to water since it is the only solvent for which the necessary parameters are available. The experimental absolute rates were obtained from ultrafast pump-probe measurements on the metal-metal charge-transfer (MMCT) band of electron transfer reactions. On the other hand, the theoretical calculations were obtained by combining MMCT resonance Raman data with an MMCT band shape analysis.

The article describes the force-induced mechanics of individual polystyrene (PS130000) in strongly poor, moderately poor, and good solvent conditions.

An experimental data to characterize the diblock copolymer interactions with a silicon nitride AFM tip is described. The surface unbinding of individual polymer blocks under conditions where a specific solvent-polymer-surface structure is expected, is also described.

Noncovalent functionalization of carbon nanotubes enables on e to tailor their properties while still preserving nearly all of the nanotube's intrinsic properties. The report describes a new nonwrapping approach to noncovalent engineering of carbon nanotube surfaces that leads to a more than 20 -fold enhancement of solubility of small SWNTs and enables superior control of the relative placement of functionalities on the nanotube surface.

Researchers collected and studied the resonance Raman spectra of (CN)5FeCNRu(NH3)5 in three solvents including water, formamide and N-methylformamide as well as the excitation profile of this compound in D2O. Findings showed that solvent dependence of the resonance Raman and infrared spectra may reflect solvent electrostatic effects on the ground electronic state wave function of the solute which is localized in the iron center. Strong solute-solvent interactions may result in solvent-induced alterations in solute electronic and nuclear structure.

Nitric oxide (NO) is important in bioregulation, and RS-NOs have an important role in regulating NO reactivity and toxicity. RS-NO was characterized using circular dichroism (CD), and NO, bound to the cystein (Cys) thiol, glutathione (GSB) or bovine serum albumin (BSA), is located with respect to the asymmetric centre of the amino acid.

Investigates the noncovalent engineering of carbon nanotube surfaces by conjugated polymers. Molecular structure of single-walled carbon nanotubes; Variation of the polymer side chain; Introduction of neutral and ionic functional groups into the nanotube surface.

An analysis of the loading rate dependence of the forces required to rupture an AFM tip from a block copolymer surface has provided insight into the structure of the surface-macromolecule contact, differentiation of the block contacting the tip, a measure of the polymer-surface binding energy, and the rigidity of the contact. Polystyrene-poly-2-vinylpyridine block copolymers were studied adsorbing to silicon nitride. Polystyrene makes stiff van der Waals contact with the silicon nitride surface in aqueous solution, while the bond of poly-2-vinylpyridine to the surface is more flexible and may involve a bridging water.