New perspectives in cell delivery systems for tissue regeneration: natural-derived injectable hydrogels.

Natural polymers, because of their biocompatibility, availability, and physico-chemical properties have been the materials of choice for the fabrication of injectable hydrogels for regenerative medicine. In particular, they are appealing materials for delivery systems and provide sustained and controlled release of drugs, proteins, gene, cells, and other active biomolecules immobilized.In this work, the use of hydrogels obtained from natural source polymers as cell delivery systems is discussed.

Poly(ethylene glycol) and hydroxy functionalized alkane phosphate self-assembled monolayers reduce bacterial adhesion and support osteoblast proliferation.

Purpose: Presently there is interest today in designing improved titanium surfaces capable of high bioactivity in order to promote strong anchorage of the bone surrounding implants while at the same time discouraging bioadhesion. Poly(ethylene glycol)-modified (PEG) alkane phosphate and OH-terminated alkane phosphates have been demonstrated to be spontaneously adsorbed onto titanium oxide surfaces and produce surfaces with different protein resistance in relation to the PEG surface density. This study aims to evaluate caries-associated Streptococcus mutans (S.

Trends in biomedical engineering: focus on Smart Bio-Materials and Drug Delivery.

The present article reviews on different research lines, namely: drug and gene delivery, surface modification/modeling, design of advanced materials (shape memory polymers and biodegradable stents), presently developed at Politecnico di Milano, Italy. For gene delivery, non-viral polycationic-branched polyethylenimine (b-PEI) polyplexes are coated with pectin, an anionic polysaccharide, to enhance the polyplex stability and decrease b-PEI cytotoxicity. Perfluorinated materials, specifically perfluoroether, and perfluoro-polyether fluids are proposed as ultrasound contrast agents and smart agents for drug delivery.

Enzymatic cross-linking of human recombinant elastin (HELP) as biomimetic approach in vascular tissue engineering.

The use of polymers naturally occurring in the extracellular matrix (ECM) is a promising strategy in regenerative medicine. If compared to natural ECM proteins, proteins obtained by recombinant DNA technology have intrinsic advantages including reproducible macromolecular composition, sequence and molecular mass, and overcoming the potential pathogens transmission related to polymers of animal origin. Among ECM-mimicking materials, the family of recombinant elastin-like polymers is proposed for drug delivery applications and for the repair of damaged elastic tissues.

Fabrication of chemically cross-linked porous gelatin matrices.

Purpose: The aim of this study was to chemically cross-link gelatin, by reacting its free amino groups with an aliphatic diisocyanate.

Methods: To produce hydrogels with controllable properties, the number of reacting amino groups was carefully determined. Porosity was introduced into the gelatin-based hydrogels through the lyophilization process.

Poly(ethylene glycol) and hydroxy functionalized alkane phosphate mixed self-assembled monolayers to control nonspecific adsorption of proteins on titanium oxide surfaces.

The spontaneous formation of alkane phosphate self-assembled monolayers (SAMs) on titanium oxide was chosen as a tool to tailor the surface physicochemical properties in terms of nonspecific adsorption of proteins. For this aim, poly(ethylene glycol)-modified (PEG) alkane phosphate was codeposited with OH-terminated alkane phosphates. X-ray photoelectron spectroscopy and ellipsometry of the resulting mixed SAMs indicate that the PEG density can be controlled by varying the mole fraction of PEG-terminated phosphates in the solutions used during the deposition process, leading to surfaces with different degrees of protein resistance.

Silk fibroin-coated three-dimensional polyurethane scaffolds for tissue engineering: interactions with normal human fibroblasts.

Silk fibroin (SF)-based or -coated biomaterials hold structural and surface properties that render them suitable for biomedical applications. In this work, we investigated the behavior of four strains of normal human adult fibroblasts (HAFs) seeded onto polyurethane foam, uncoated (PUF) or SF coated (PUF/SF). HAF adhesion within 3 h to PUF/SF was 2-fold that of adhesion to PUF.

Silk fibroin/poly(carbonate)-urethane as a substrate for cell growth: in vitro interactions with human cells.

Silk fibroin (SF)-based or -coated biomaterials are likely to be endowed with structural and surface properties that render them particularly apt for biomedical applications. In this work we investigated the behavior of four different strains of normal human adult fibroblasts that had been seeded onto membranes made up of poly(carbonate) urethane (PCU), the surfaces of which had or had not been homogeneously coated with SF. Cell adhesion within 3h to the SF-coated PCU films was 2.