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Bacterial colonization of implanted biomaterials remains one of the most challenging complications in orthopedics and trauma surgery, with extremely high social and economic costs. Antibacterial coating of implants has been advocated by many experts as a possible solution to reduce the burden of implant-related infection and several different solutions have been proposed in the last decades. However, while most of the investigated technologies have shown their efficacy in vitro and/or in vivo, only few were able to reach the market, due to clinical, industrial, economic and regulatory issues. Hyaluronic acid composites have been previously shown to possess antifouling capabilities and have been used in various clinical settings to reduce bacterial adhesion and mitigate biofilm-related infections. Recently, a fast-resorbable, hyaluronic-based hydrogel coating was developed to protect implanted biomaterials in orthopedics, trauma and maxillofacial surgery. Preclinical and clinical testing did show the safety and efficacy of the device that can be intraoperatively loaded with one or more antibiotics and directly applied by the surgeon to the implant surface, at the time of surgery. Here, we review the current evidence concerning this very first antibacterial coating of implants and outline the economic impact of the possible large-scale application of this technology.

With the high occurrence of cardiovascular disease and increasing numbers of patients requiring vascular access, there is a significant need for small-diameter (

In recent years there has been a growing interest for the development of tubular scaffolds employed to assist the replacement of small blood vessels. Materials designed for this purpose need to be biodegradable, have good mechanical properties and improve cell adhesion, proliferation and differentiation. To obtain biomaterials with these properties, electrospinning seems to be one of the most useful technique. Several biodegradable synthetic polymers or constituents of the extracellular matrix (ECM) have been electrospun showing optimal mechanical properties and biodegradability. However, such polymers are lacking in versatile chemical structure affordable to immobilize growth factors or chemokines. The glycosaminoglycan heparin is able to bind several growth factors like vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) and, when grafted onto the scaffold surface it is able to attract cells thus improving their proliferation and differentiation. Aim of this research was the production and the preliminary in vitro biological characterization of a new biodegradable material, obtained by electrospun a polyaminoacid-graft-polyester copolymer. The electrospun biomaterial has been successfully grafted with heparin exploiting the better chemical reactivity of the polyaminoacid portions of the graft copolymer. Then its morphology has been investigated by scanning electron microscopy (SEM) and the potential biodegradability of the material has been studied until 60 days. Preliminary biological data in vitro, on human endothelial cells, show a good compatibility of the scaffold obtained by electrospinning, with regard to cell adhesion and proliferation. Experiments are in progress to evaluate the effects of heparin on cell differentiation.

HYDROPHOBIC POLYMER COATED SUPERPARAMAGNETI NANOPARTICLES FOR ANTICANCER DRUG DELIVERY LICCIARDI M.1, SCIALABBA C.1, AMATO G.1, CAVALLARO G.1, GIAMMONA G.1,2 1Dipartimento di Scienze e Tecnologie Molecolari e Biomolecolari (STEMBIO), University of Palermo, via Archirafi 32, 90123, Palermo, Italy. 2IBF-CNR, via Ugo La Malfa, 153, 90143 Palermo, Italy. Superparamagnetic Fe3O4 nanoparticles have been recently used in drug delivery applications [1-4]. In this study, a novel approach to prepare magnetic polymeric nanoparticles containing superparamagnetic domains and hydrophobic polymeric shell using microemulsion-solvent evaporation method is reported. PHEA-IB-poly(ButMA) copolymer was used as coating copolymer to obtain magnetic nanoparticles by O/W emulsion of polymer solution in the presence of 10 nm Fe3O4 superparamagnetic nanoparticles and the anticancer drug flutamide. Obtained magnetic nanoparticles were characterized by DLS, TEM and magnetometry. The results obtained from TEM (Figure 1) and DLS analysis showed that the particles are spherical with average size of about 250 nm. The magnetic measurement studies revealed the superparamagnetic behavior of the nanoparticles and the presence of superparamagnetic domains inside nanoparticles. Cytotoxicity profile of the nanoparticles on LNCaP cells showed that the flutamide loaded nanoparticles, compared to free flutamide, caused a significant reduction of LNCaP cells proliferation induced by DHT. In vivo biodistribution of drug loaded into nanoparticles in rats subjected to an external magnetic field showed important quantitative differences in comparison with that obtained in the control group. FLU was concentrated most conspicuously in kidney, and less in all the other organs (Figure 2). This modified biodistribution profile demonstrated that these nanoparticles are able to control drug biodistribution by means of an external magnetic field that may attract the nanoparticles in a specific site of the body or organ. Obtained data shows that coated Fe3O4 superparamagnetic nanoparticles are potentially useful for in vivo applications in treatment of tumors. References [1] Adv. Drug Delivery Rev. 16, 321–334, 1995. [2] Radiology 36, 153–163, 1996. [3] J. Microencapsulation,. 13, 245–255, 1996. [4] Life Sci., 44,. 175–186, 1989.