Bovine submaxillary mucin (BSM) adsorption at solid/liquid interfaces and surface forces. Colloids Surf

ABSTRACT Bovine submaxillary mucin (BSM) was obtained from salivary glands through successive precipitations and dissolutions. It was labelled by acetylation with [ l-"Cl acetic anhydride. Direct and continuous measurement of the total (reversible and irreversible) adsorption has been taken on muscovite mica, polyethylene, oxidized polyethylene, silicone and poly-(vinyl pyrrolidone) grafted silicone films. Force measurements between mucin layers adsorbed on two mica surfaces have been made in the distance range O-600 nm. Adsorption/ desorption and force distance measurements allow us to distinguish between reversibly and irreversibly adsorbed protein molecules. The results also show that chemical modification of polymer surfaces enhances mucin adsorption

Enhancement of the Solubility and Efficacy of Poorly Water-Soluble Drugs by Hydrophobically-Modified Polysaccharide Derivatives

International audiencePurposeThis work was intended to develop and evaluate a new polymeric system based on amphiphilic carboxymethylpullulans (CMP49C8 and CMP12C8) that can spontaneously self-assemble in aqueous solutions and efficiently solubilize hydrophobic drugs.MethodsThe self-assembling properties of CMP49C8 and CMP12C8 were characterized by fluorescence spectroscopy and surface tension measurements. The solubilization of benzophenone and docetaxel was assessed from surface tension measurements, UV spectrometry and HPLC assays. The in vitro cytoxicity of CMP49C8 solutions and the docetaxel commercial vehicle (Tween 80®/Ethanol–water) were evaluated in the absence and in the presence of docetaxel.ResultsCompared to CMP12C8, CMP49C8 in aqueous solutions appeared to self-organize into monomolecular aggregates containing hydrophobic nanodomains, and to significantly increase the apparent solubility of benzophenone. Docetaxel solubility could also be improved in the presence of CMP49C8 but to a lower extent due to the surface properties of the drug. Nevertheless, in vitro, the cytotoxicity studies revealed that against cancer cells, the CMP49C8-docetaxel formulation was equipotent to the commercial docetaxel one. Furthermore, in the absence of the drug, CMP49C8 appeared less cytotoxic against macrophages than the Tween® 80/Ethanol–water.ConclusionsCMP49C8 is a good candidate for solubilizing hydrophobic drugs and could be applied to docetaxel formulations

Structural characterisation of a new heparinisable material based on ethylene/vinyl alcohol/vinyl acetate terpolymer and a poly(amido-amine)

Partially hydrolyzed ethylene/vinyl acetate copolymers (EVALVA) were modified by covalent binding of a heparin-complexing poly(amido-amine) (N2LL). The physicochemical characterisation of the starting and modified materials was carried out through thermal analysis, dynamic mechanical thermal analysis, mechanical tensile test, contact angle, potentiometric measurements, water uptake and FT-IR spectroscopic measurements. The behaviour of this material in both the dry and the wet state was stressed, evidencing the different orientation of the chemical groups, which are buried or exposed according to whether its nature is hydrophilic or hydrophobic. The material was heparinised, and the presence of heparin was revealed by energy dispersive X-ray analysis (EDAX) and FT-IR