The most common approach for achieving sustained drug release is by the use of hydrophilic polymeric excipients directly compressed with active ingredients into tablets. Hydrophilic polymers swell in the presence of water to form hydrogel structures from which drugs are released by slow diffusion. The purpose of this study was to prepare a floating drug delivery system of levofloxacin, a fluoro...

The aim of the work reported herein was to implement process analytical technology (PAT) tools during hot melt extrusion (HME) in order to obtain a better understanding of the relationship between HME processing parameters and the extruded formulations. For the first time two in-line NIR probes (transmission and reflectance) have been coupled with HME to monitor the extrusion of the water insol...

Porous scaffolds for cancellous bone graft substitutes were prepared from new experimental biodegradable aliphatic polyurethane elastomers with varying hydrophilicity. The ratios of the hydrophilic-to-hydrophobic content in the polymers were 30-70, 50-50, and 70-30%, respectively. The hydrophilic component consisted of poly(ethylene oxide) diol and the hydrophobic component of poly(epsilon-capr...

We report the fabrication of shortened electrospun polymer fibers with a well-defined concentrated polymer brush. We first prepared electrospun nanofibers from a random copolymer of styrene and 4-vinylbenzyl 2-bromopropionate, with number-average molecular weight Mn=105 200 and weight-average molecular weight Mw=296 700 (Mw/Mn=2.82). The fibers had a diameter of 593±74 nm and contained initiati...

The effect of three different types of polymer chain structures on the polymer release from hydrophilic matrix tablets was investigated by comparing a synthetic semi-crystalline linear polymer (PEO), a branched amorphous polysaccharide (dextran) and an amorphous substituted cellulose derivative (HPMC). The polymer release rates for tablets containing mixtures of high and low molecular weight gr...

The hydrophilicity ageing of polypropylene (PP) and polyethylene terephthalate (PET) films treated by nonthermal plasma usually takes over 150 days. In the present work, the accelerated ageing induced by hydrogen atoms and ultraviolet (UV) radiation with a wavelength of = 253.7 nm was studied. It was experimentally found that the hydrogen atoms restored the modified polymers to their original h...

Monte Carlo simulations have been carried out for an off-lattice model of an amphiphilic polymer at a hydrophobic/hydrophilic interface. The model system consists of a polynorbornene backbone with poly(ethylene oxide) (PEO) grafts modelled atomistically at an idealized interface between hydrophobic and hydrophilic regions, which are represented by external potentials. Results are presented for ...

α-Functionalized acrylamides have not been considered as an effective monomer design due to their poor polymerizability, although the analogues, α-functionalized acrylates, are attractive monomers of which polymers exhibit characteristic properties. In this article, we report the first example of radical polymerization of α-functionalized N,N-disubstituted acrylamide affording thermo-responsive...

Synthetic polymers of a specific shape and size play major role in drug delivery systems. Dendrimers are unique synthetic macromolecules of nanometer dimensions with a highly branched structure and globular shape with potential applications in gene and drug delivery. We examine the interaction of several dendrimers of different compositions mPEG-PAMAM (G3), mPEG-PAMAM (G4) and PAMAM (G4) with h...

Certain natural organisms use micro-patterned surface chemistry, or icenucleating species, to control water condensation and ice nucleation for survival under extreme conditions. As an analogy to these biological approaches, it is shown that functionalized, hydrophilic polymers and particles deposited on the tips of superhydrophobic posts induce precise topographical control over water condensa...