Effective drug delivery by PEGylated drug conjugates.

Compositions and methods for forming hydrogels in situ through a combination of physical and chemical crosslinking processes are provided in which physical crosslinking is mediated by one or more natural or synthetic components that stabilize the a hydrogel-forming precursor solutions at a deposition site for a period of time sufficient for more resilient chemical crosslinks to form. Methods of using such hydrogels as tissue coatings to prevent postsurgical adhesion formation, as tissue augmentation or luminal occlusion aids, as matrices for carrying cells, drugs or other bioactive species, as tissue sealants or adhesives, and as medical device coatings also are provided.

In situ polymerizable hydrogels

This critical review is concerned with the recent advances in graft polymerisation techniques involving cellulose and its derivatives. It summarises some of the features of cellulose structure and cellulose reactivity. Also described are the various techniques for grafting synthetic polymers from the cellulosic substrate. In addition to the traditional grafting techniques, we highlight the recent developments in polymer synthesis that allow increased control over the grafting process and permit the production of functional celluloses that possess improved physical properties and chemical properties (189 references).

Cellulose modification by polymer grafting: a review

This invention related to a tissue-adhesive sheet comprising a homogeneous, preformed and cross-linked matrix formed from one or more polymers, and having at least one surface that, in use, is exposed, at least one of said one or more polymers being a synthetic polymer and having appendant functional groups of a first form, cross-linking of said matrix being via a proportion of said functional groups of the first form, and the remainder of said functional groups of the first form being free. The sheet is particularly useful as a tissue adhesive and sealant, and is intended for topical application to internal and external surfaces of the body for therapeutic reasons. The invention further relates to sheets comprising a scaffold material, three-dimensional articles formed from similar material to that of the sheet and to implantable medical devices coated with such material.

Tissue-adhesive materials

Chemistry of polyethylene glycol conjugates with biologically active molecules

Attachment of drugs to polyethylene glycols

Polyethylene glycol derivatives of procaine.

Polymers containing phenethylamines.

α-Trimethylsilyl acrylic acid and its methyl ester were prepared in good yield starting from 1,2-dibromoethyltrimethylsilane. These monomers were polymerized with difficulty by free radicals to viscous polymers, but gave solid copolymers with styrene. The methyl ester was also a weak monomer in anionic polymerization. This non-reactivity is due to the steric effect of the α-trimethylsilyl group adjacent to the double bond.

SYNTHESES AND POLYMERIZATION OF α-TRIMETHYLSILYL ACRYLIC MONOMERS

The grafting of the potassium alkoxide derivative of poly(ethylene oxide) on poly(methyl methacrylate) in homogeneous solution in toluene was studied. The alkoxide was prepared by reaction with potassium metal with methanolic potassium methoxide, or with potassium naphthalene. The last was the most suitable for the systematic investigation of the grafting process. Soluble graft polymers were formed, and essentially the initial poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) participated in the production of graft polymer. The composition of the graft polymers and the frequency of grafting of the side chains were determined by NMR. The solubility of the graft polymers in methanol and water increased with increasing PEO contents, while the melting ranges decreased. Fractionation of the crude graft polymers showed that the grafting reaction was random, and graft polymers containing one PEO side chain per about 10–170 MMA units were obtained.

Albert Zilkha

Papers

Attachment of drugs to polyethylene glycols

Polyethylene glycol derivatives of procaine.

Polymers containing phenethylamines.

SYNTHESES AND POLYMERIZATION OF α-TRIMETHYLSILYL ACRYLIC MONOMERS

Grafting of poly(ethylene oxide) on poly(methyl methacrylate) by transesterification