Medical CA

A medical and surgical adhesive compostion is described which provides an increased elasticity of the adhesive film and which is free of side effects, comprising 2-ehtyl cyanoacrylate, butyl acrylate and 3-methacryloxy sulfolane.

Simultaneous cellular resistance to multiple lipophilic drugs represents a major problem in cancer chemotherapy. This drug resistance may appear clinically either as a lack of tumor size reduction or as the occurrence of clinical relapse after an initial positive response to antitumor treatment. The resistance mechanism can have different origins either directly linked to specific mechanisms developed by the tumor tissue or connected to the more general problem of distribution of a drug towards its targeted tissue.

This review considers the use of poly(alkylcyanoacrylates) (PACAs) as biomedical materials. We first present the different aspects of the polymerization of alkylcyanoacrylate monomers and briefly discuss their applications as skin adhesives, surgical glues and embolitic materials. An extensive review of the developments and applications of PACAs as nanoparticles for the delivery of drugs is then given.

Latent fingerprints are developed by exposing them to vapours generated from a thin film of a storage stable cyanoacrylate monomer and a thixotropic additive in sufficient amount to render the composition substantially non-flowable. The monomer film should have a surface area at least 129 sq. cm.

An envelope package for the monomer composition has inner polyethylene surfaces. The envelope may be peeled open to expose the inner surfaces coated with a film of the composition.

Currently, new formulations of -cyanoacrylic tissue adhesives, are being studied for the repair of soft and hard tissue in order to improve properties such as: biodegradability, biocompatibility bone flexibility (in the soft tissue applications) and ease of handling. This paper presents a review of scientific literature related to new formulations of -cyanoacrylic adhesives and medical applications.

Poly(Styrene-block-IsoButylene-block-Styrene) (‘‘SIBS’’) is a biostable thermoplastic elastomer with physical properties that overlap silicone rubber and polyurethane. Initial data collected with SIBS stent-grafts and coatings on metallic stents demonstrate hemocompatibility, biocompatibility and long-term stability in contact with metal.

This highlight is about my metamorphosis from a cationic polymerization chemist to a biomaterialist (no pun intended) and some of the main events on the road. My earlier career faded away with the discovery of living cationic polymerizations, chronicled in my 1999 highlight, but it also put me on the road to designed biomaterials.

Polymeric materials and methods that realize a gel-type intraocular lens that is formed in situ within the lens capsule of the eye. The polymeric material of the intraocular lens includes reactive end groups that effectively bond with lens capsule walls, thus eliminating space between the intraocular lens and the lens capsule walls and significantly reducing the proliferation of lens epithelial cells which can cause unwanted posterior capsule opacification.

A new material for the microencapsulation of biological systems was discovered and characterized with regards to the effects of reaction conditions on product yield. By using poly(cyanoacrylate ester), membrane microcapsules were produced with sufficient strength and porosity to be effective in a process environment for the immobilization and protection of encapsulated material. After synthesizing numerous monomeric cyanoacrylate esters, the n-butyl derivative was discovered to give the best results with regards to microcapsule formation.

Alkyl cyanoacrylate instant adhesives are widely used because of their fast cure speed and versatility on a large number of substrates. Recent performance improvements, such as increased thermal resistance, resulted from the addition of latent acids and polymers, which do not copolymerize with the adhesive monomer, to the adhesive formulations. However, use of these additives can increase fixture time or reduce the final adhesive strength.