A study of macroderm a and macroderm L monolayers and their two-dimensional compatibility

 Spread monolayers of two new skin permeation enhancers, MacroDerm A and MacroDerm L were investigated at the water/air interface as a function of temperature and of subphase composition. Both components did not seem to be markedly affected by changes in ionic strength and by the presence of metal ions in the subphase. The two-dimensional binary system MacroDerm A –MacroDerm L was also studied at the water/air interface at 298 K on pure water subphase. The behavior of surface areas, surface compressional moduli and collapse pressure as a function of molar ratios of components shows that MacroDerm A and MacroDerm L are miscible. Received: 17 December 1996 Accepted: 5 March 1997     

Bioactive polymeric materials for targeted administration of active agents: synthesis and evaluation

Bioerodible polymers displaying both stealth and targeting properties for the preparation of nanosystems for targeted and controlled delivery of fibrinolytic drugs to the thrombus were prepared by straightforward synthetic routes and characterized. Poly[(maleic anhydride)-alt-(butylvinyl ether)]s were synthesized in the presence of dodecyl mercaptan as chain transfer agent allowing for the preparation of copolymers with tunable molecular weight. 2-Methoxyethanol hemiesters containing antiopsonizing molecules of poly(ethylene glycol) were prepared and further biofunctionalized with a Fab fragment by a two-step reaction. In vitro biocompatibility investigation of the prepared materials supported their suitability for biomedical applications.     

Conformational study of isotactic poly[(S)-5-methyl-1-heptene] and poly[(S)-2-methylbutyl vinyl ether] by IR spectroscopy

Infrared (IR) investigation of structurally analogous optically active polymers such as poly[(S)-5-methyl-1-heptene (1)] and poly[(S)-2-methylbutyl vinyl ether (2)] was carried out in the solid state, in the molten state, and in solution. Vibrational data are in accordance with the existence of helical conformations in solution and in the molten state for both polymers, confirming the previous suggestions based on optical rotation measurements. In particular, an accurate examination of the spectral region between 850 and 700 cm^?1, where characteristic absorptions of the sec-butyl group occur, enables us to assign the medium intensity band at 827 cm^?1 (present in both polymers in the solid state) to the GTTG^?T conformation of the side chains.     

Synthesis and characterization of functional polyesters tailored for biomedical applications

This work aimed at the development of bioactive polymeric materials to be used for targeted drug delivery and tissue engineering applications. The proposed strategy was based on the design of macromolecular systems whose functionality can be easily modified. Polyesters containing side‐chain end capped by primary hydroxyl groups were synthesized by polyaddition of oxetanes and carboxylic anhydrides catalyzed by quaternary onium salts. The polyaddition of bis(oxetane) with different dicarboxylic acids was also investigated. In all cases, oxetane monomers contained one hydroxyl group either free or protected by a benzyl group. The polymer yield and molecular weight were relatively high when aromatic anhydrides were used. In all other cases, low conversions or no polymerization at all were obtained. In a parallel research line, several alkanols were successfully employed to synthesize different α,β′,β‐trisubstituted‐β‐lactones. These monomers were prepared in five steps starting from diethyl oxalpropionate according to established synthetic routes. Final yields depended on both preparation method and side‐chain structure. By using quaternary ammonium salts as catalysts, the synthesized functional lactones underwent anionic ring opening polymerization leading to the corresponding homopolymers and copolymers in fairly good yields. The prepared polymeric materials were extensively characterized by spectroscopic techniques, size exclusion chromatography, and thermal analysis. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2459–2476, 2008     

Development of Electrospun Three‐arm Star Poly(ε‐caprolactone) Meshes for Tissue Engineering Applications

We have developed three‐dimensional electrospun microfibrous meshes of a novel star branched three‐arm poly(ε‐caprolactone) (*PCL) as potential scaffolds for tissue engineering applications. The processing conditions required to obtain uniform fibers were optimized by studying their influence on fiber morphology and size. Polymer molecular weight and solution feed rate influenced both the mesh microstructure and the tensile properties of the developed mats. Electrospun samples were also tested for their mechanical properties in wet conditions, showing higher yield strength and strain in comparison to that observed in dry conditions. Cell culture experiments employing MC3T3‐E1 osteoblast like cells showed good cell viability adhesion and collagen production on the *PCL scaffolds.

     

Azobenzene containing polymers: what is yet viable with aged liquid crystals

A Commentary on the paper “Photochromic liquid crystalline polymers. Main chain and side chain polymers containing azobenzene mesogens„, by A. S. Angeloni, D. Caretti, C. Carlini, E. Chiellini, G. Galli, A. Altomare, R. Solaro and M. Laus. First published in Liquid Crystals, 4, 513-527 (1989).     

Dead Sea Minerals loaded polymeric nanoparticles

Therapeutic properties of Dead Sea Water (DSW) in the treatment of skin diseases such as atopic dermatitis, psoriasis and photo aging UV damaged skin have been well established. DSW is in fact rich in minerals such as calcium, magnesium, sodium, potassium, zinc and strontium which are known to exploit anti-inflammatory effects and to promote skin barrier recovery. In order to develop a Dead Sea Minerals (DSM) based drug delivery system for topical therapy of skin diseases, polymeric nanoparticles based on Poly (maleic anhydride-alt-butyl vinyl ether) 5% grafted with monomethoxy poly(ethyleneglycol) 2000 MW (PEG) and 95% grafted with 2-methoxyethanol (VAM41-PEG) loaded with DSM were prepared by means of a combined miniemulsion/solvent evaporation process. The resulting nanoparticles were characterized in terms of dimension, morphology, biocompatibility, salt content and release. Cytocompatible spherical nanoparticles possessing an average diameter of about 300 nm, a time controlled drug release profile and a high formulation yield were obtained.     

Blends of Poly(Buty1ene Terephthalate) with Thermotropic Liquid Crystalline Polyesters. Morphology and Thermal Behavior

Blends of poly(butylene terephthalate) with liquid crystalline poly (decamethylene 4, 4′-terephthaloyldioxydibenzoate) were studied in all the composition range by optical and electron microscopy and differential calorimetry. The morphology and phase transitions of the blends are markedly influenced by the composition and thermal history. The results suggest the occurrence of miscibility phenomena between the two components in the amorphous phase.