The complex interaction of polyelectrolyte multilayers (PEMs) physisorbed onto end-grafted polymer brushes with focus on the temperature-responsive behavior of the system is addressed in this work. The investigated brush/multilayer composite consists of a poly(styrene sulfonate)/poly(diallyldimethylammonium chloride) (PSS/PDADMAC) multilayer deposited onto the poly(N-isopropylacrylamide-b-dimet...

Hydrogel nanocomposites containing silver nanoparticles of size 15–21 nm were prepared by diffusion and in-situ chemical reduction in chemically crosslinked polymers based on N-acryloyl-N′-ethyl piperazine (AcrNEP) and N-isopropylacrylamide (NIPAM). The polymer chains of the hydrogel network offered control and stabilization of silver nanoparticles without the need for additional stabilizers. T...

This paper describes how changes in the refractive index of single hydrogel nanoparticles (HNPs) detected with near-infrared surface plasmon resonance microscopy (SPRM) can be used to monitor the uptake of therapeutic compounds for potential drug delivery applications. As a first example, SPRM is used to measure the specific uptake of the bioactive peptide melittin into N-isopropylacrylamide (N...

This paper describes the preparation and characterization of a new type of composite nanoparticle, where the structure consists of a nontoxic hydrogel polymer network that encapsulates a gold shell/silica core. These composite nanoparticles are being developed as photothermally responsive drug-delivery vehicles that undergo structural changes slightly above physiological temperature. A unique p...

objective(s) in this study, a kind of ph sensitive composite membrane was prepared and drug permeation through it was investigated in terms of ph. rationale of this study originated from the fact that a ph change which may be a result of a disease state in the body can trigger drug release. materials and methods  here, a kind of ph sensitive composite membrane containing different nanoparticle ...

ABC triblock copolymers with a poly(ethylene glycol) (PEG) midblock have attractive properties for biomedical applications because of PEG's favorable properties regarding biocompatibility and hydrophilicity. However, easy strategies to synthesize polymers containing a PEG midblock are limited. In this study, the successful synthesis of a heterofunctional PEG macroinitiator containing both an az...

We have shown that the lattice fluid hydrogen bond ~LFHB! model can successfully quantify the first-order volume transition in hydrogels. The model predicts that a critical balance of hydrophilic and hydrophobic interactions is required for a gel to exhibit a discontinuous volume transition. In this work we will report the swelling behavior of a new thermoreversible copolymer hydrogel, which ha...

One-end-connected short poly(ethylene glycol) (PEG) side chains were facilely introduced into the poly(N-isopropylacrylamide) (PNIPAm) nanocomposite hydrogel (NC gel) via in situ copolymerization of NIPAm monomer and PEG macromonomer in the aqueous suspension of hectorite clay Laponite XLS. The NC gels were characterized with Fourier transform infrared and x-ray photoelectron spectroscopy for t...

Copolymers of 2-dimethyl(aminoethyl) methacrylate (PDMAEM) with N-isopropylacrylamide (NIPAM) were evaluated for their potential to enhance transgene expression of plasmid DNA (pDNA) and gene delivery by adenovirus vectors. The polymers of varying compositions and molecular weights (MW) were synthesized by free-radical polymerization. Polyelectrolyte complexes (PECs) were prepared with differen...