Journal Article

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.

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.

Ocular tolerance to cyanoacrylate tissue adhesives was evaluated in rabbits. In the experimental studies, tissue adhesives were implanted intralamellarly, subconjunctivally, and in the anterior chamber. The eyes were examined clinically and histologically at different time intervals. In the cornea and conjunctiva, the adhesive reacted as any inert material. The reaction was considerably less than that to silk or catgut. In the anterior chamber, the reaction was moderate in most cases.

Purpose: To analyze the antibacterial effects in vitro of ethyl- cyanoacrylate (EC) tissue adhesive in different application volumes. Methods: Volumes of 4, 6, 8, 10, 12, 14, 25, and 35 μl of EC were applied onto the sur- face of monolayer cultures of Staphylococcus aureus (ATCC25924), Streptococcus pneumoniae (ATCC49619), Escherichia coli (ATCC25922), Pseudomonas aeruginosa (ATCC27853), and Klebsiella pneumoniae (ATCC13883). The diameter of each EC drop was measured, and the area of the circle of EC (formed after its appli- cation onto the monolayer culture) was calculated.

The aim of the study was to compare suture, clip and clip combined with topical N-butyl cyanoacrylate in an experimental model of gastric perforation. Sixty Wistar-Albino rats were divided into three groups. Midline laparotomy was performed and a 4 mm puncture was done on the anterior surface of the stomach. Closure was performed by sutures in the first group, clip in the second group, and clip with topical cyanoacrylate in the third group. Ten rats underwent a re-laparotomy on the 3rd and 7th days, respectively.

Cyanoacrylates (CAs) were not widely adopted for medical use until recently because of lingering concerns regarding the initial tissue toxicities of the short-chain CAs. The medium-chain CAs, primarily butyl-cyanoacrylate, have been widely used in Europe and Canada for several decades and have gone a long way in dispelling any lingering concerns about tissue toxicity. The newer, longer chain CA,octyl-2-cyanoacrylate (2-OCA), now has been approved for multiple uses in the United States and has achieved widespread acceptance by the medical and lay communities.