OBJECTIVE To investigate cross-linked hydrogels prepared via inverse emulsion polymerization to entrap poorly aqueous soluble drugs. Polyethylene glycol cross-linked acrylic polymers were synthesized and the loading and release of curcumin, a model hydrophobic drug, was investigated. METHODS Physicochemical characteristics of hydrogels were studied with (13)C nuclear magnetic resonance, Fouri...

Polymeric nanoparticles (NPs) have great application potential in science and technology. Their functionality strongly depends on their size. We present a theory for the size of NPs formed by precipitation of polymers into a bad solvent in the presence of a stabilizing surfactant. The analytical theory is based upon diffusion-limited coalescence kinetics of the polymers. Two relevant time scale...

ARTICLES The Ecology of Early Food Production in Mesopotamia: K. V. Flannery Prehistoric farmers and herders exploited a series of adjacent but contrasting climatic zones. Crystallization and Molecular Folding: P. H. Lindenmeyer The properties of high polymers are very sensitive to the way molecules fold during crystallization. Meteorites and the Moon: H. C. Urey ..................................

We study the dynamics of single DNA molecules driven by an electric field into a stationary obstacle. These collisions are broadly classified as "hook" and "roll-off" events. We show that obstacle-induced electric field gradients stretch impacting DNA and thus greatly influence the hooking probability. Consequently, in addition to collision geometry, determination of the hooking probability dep...

Responsive polymeric assemblies and hybrid superstructures fabricated from stimuli-sensitive polymers and inorganic nanoparticles (NPs) have been the subject of extensive investigations during the past few decades due to their distinct advantages such as an improved water solubility, stimuli-responsiveness, excellent biocompatibility, and facile introduction of functional units. In addition, th...

Attachment of drugs to high molecular weight polymers can significantly improve both tumor targeting and therapeutic efficacy due to the enhanced permeability and retention effect observed in tumor tissue. However, the commercial availability of well-defined water-soluble polymeric systems with narrow polydispersities that are biocompatible, nontoxic, and nonimmunogenic is rather limited. To ad...

We investigate the statistical mechanics of polymers with bending and torsional elasticity described by the helical wormlike model. Noticing that the energy function is factorizable, we provide a numerical method to solve the model using a transfer matrix formulation. The tangent-tangent and binormal-binormal correlation functions have been calculated and displayed rich profiles which are sensi...

This thesis documents the synthesis and characterization of an elastomeric polymer that is oxygen sensitive and can be interrogated using Magnetic Resonance Imaging (MRI) or Magnetic Resonance (MR) technology to report the oxygen tension in vivo at the site of implant. The polymer was tested for its sensitivity in response to oxygen, and the specificity of response to oxygen was verified. Oxyge...

0014-3057/$ see front matter 2008 Elsevier Ltd doi:10.1016/j.eurpolymj.2008.07.014 * Corresponding authors. Tel.: +1 865 5763820; (G. Cheng), tel.: +1 865 5744974; fax: +1 865 57415 E-mail addresses: [email protected] (G. Chen (K. Hong). The conformation of newly synthesized amphiphilic poly(methoxyoligo(ethylene oxide) norbornenyl esters) macro-homopolymers in dilute solutions of toluene-d8 and ...

in this paper, electronic, structural, and spectroscopic properties of mono-, di-, tri-, andtetrafluorothiophenes and their radical cations are studied using the density functional theory andb3lyp method with 6-311++g** basis set. also the effects of the number and position of thesubstituent on the electrochemical properties of the thiophene ring have been studied usingoptimized structures obta...