DC Bead is a FDA cleared embolisation device for the treatment of hypervascular tumours and arteriovenous malformations. This product is currently evaluated in a number of centres in Europe as an embolic device for transarterial chemoembolisation (TACE). The beads consist of poly(vinyl alcohol) microspheres modified with sulfonic acid groups and are available at different size ranges varying from 100 to 900 microm in diameter.
View Article and Find Full Text PDFJ Mater Sci Mater Med
December 2006
This study describes the comparative performance of four commercially available microspherical embolisation products: Embosphere, Embogold, Contour SE and Bead Block. A series of in vitro evaluations were designed to assess the mechanical and biological characteristics of these biomaterials. Size distribution analysis revealed sieving techniques used to fractionate the embolics produced similar size distributions.
View Article and Find Full Text PDFPurpose: The purpose of this investigation is to present the in vitro characterization and detailed drug-loading procedure for DC Bead, a microsphere product that can be loaded with chemotherapeutic agents for embolization.
Materials And Methods: DC Bead is an embolic microsphere product that is capable of being loaded with anthracycline drugs such as doxorubicin just before administration in a transarterial chemoembolization (TACE) procedure. Beads can be loaded from solutions prepared from doxorubicin powder or the doxorubicin HCl formulation.
Growth of antibody-secreting hybridomas requires special conditions such as serum-free defined media containing growth factors and vitamins. However, the surface on which these cells can proliferate has been shown to play an important role. Phosphorylcholine (PC)-based polymers are zwitterionic compounds with nonbiofouling properties.
View Article and Find Full Text PDFPhosphorylcholine-based polymers have been used commercially to improve the biocompatibility of coronary stents. In this study, one particular polymer is assessed for its suitability as a drug delivery vehicle. Membranes of the material are characterized in terms of water content and molecular weight cut-off, and the presence of hydrophilic and hydrophobic domains investigated by use of the hydrophobic probe pyrene.
View Article and Find Full Text PDFThe preparation and characterisation of a new phosphorylcholine (PC)-coated silicone hydrogel contact lens for use in extended wear is described. The Michael-type addition of amines to acrylates forms the basis of the synthesis of a novel silicone-based macromer with hydrophilic functionality. It is demonstrated that this macromer can be combined with other silicone-based monomers, hydrophilic monomers and crosslinker to produce a contact lenses formulation.
View Article and Find Full Text PDFCopolymers of 2-methacryloyloxyethylphosphorylcholine (MPC) and lauryl methacrylate (LMA) of molar ratios MPC: LMAX where x = 1, 2 or 4, have been synthesised by two different free-radical polymerisation techniques. The solubility characteristics of the resulting materials were investigated in a variety of water: alcohol solvent mixtures and found to be influenced not only by the molar ratio of MPC: LMA, but also the method of synthesis. A window of solubility was observed for certain copolymers and the alcohol used in the solvent mixture was also found to have a profound influence on the solubility profile of the polymers.
View Article and Find Full Text PDFNonlinearity in the diastereoselectivity of epoxidation of allylic alcohols with mixtures of titanium isopropoxide, tertbutyl hydroperoxide, and diethyl tartrate was observed. Racemic and enantiomerically pure alcohols E-2-methyl-4-hexen-3-ol and E-1-methoxy-5-(O-tertbutyldimethylsilyloxy)-2-penten-4-ol were prepared. Epoxidation reactions were carried out with Ti(OPri)4 and ButOOH accompanied by diethyl tartrate of varying enantiomeric purity.
View Article and Find Full Text PDFNew chiral Schiff base complexes have been obtained by condensation of 2,2'-diamino-1,1'-binaphthalene or 1,2-diaminocyclohexane and various salicylaldehydes and by subsequent metalation with manganese, iron, cobalt, nickel, copper, or zinc. The complete (1)H and (13)C NMR characterization of the ligands is reported, as are the X-ray crystal structures of (1R,2R)-(-)-N,N'-bis[3-(N,N-dimethylamino)salicylidene]-trans-1,2-cyclohexanediimine and [(1R,2R)-(-)-N,N'-bis(salicylidene)-trans-1,2-cyclohexanediiminato]copper(II). The new chiral manganese complexes have been evaluated in the oxygenation of prochiral olefins and sulfides using sodium hypochlorite, hydrogen peroxide, or N-methylmorpholine N-oxide/m-chloroperbenzoic acid as oxidant.
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