Biomedical

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.

The bonding strength between bone and α-2-cyanoacrylate polymers, with or without the addition of powdered hydroxyapatite, was determined. The tensile strength of a bone-cyanoacrylatebond was measured for each polymer: 4.31± 0.88 M Pa(methyl-), 5.74 ± 0.62 MPa (ethyl-), and 8.33 ± 0.41 MPa (isobutyl-). The tensile strength of the isobutyl-2-cyanoacrylatebond increased to 12.03 ± 0.72 MPa with the addition of 10% (w/v) hydroxyapatite before decreasing to 7.89 ± 0.58 Mpa on addition of 15% (w/v)hydroxyapatite.

Cyanoacrylate, a synthetic adhesive, is a fast polymerizable liquid monomer. Serendipity led to the discovery of cyanoacrylate adhesives in 1951. Today, a specific cyanoacrylate monomer, 2-octyl cyanoacrylate, is being used in a topical medical adhesive formulation. The only over-the-counter cyanoacrylate-based product cleared by the Food and Drug Administration is Colgate ORABASE Soothe.N. Seal Liquid Protectant. Upon application, this liquid monomer formulation polymerizes instantly into a thin, flexible polymer film that adheres tenaciously to mucosal tissue.

The efficacy of primaquine-loaded polyisohexylcyanoacrylate (PIHCA) nanoparticles was evaluated using J774G8 macrophage-like cells infected with Leishmania donovani: as an in vitro model of visceral leishmaniasis. The in vitro antileishmanial activity of primaquine-loaded nanoparticles showed a 21-fold increase in ED50 compared with free primaquine. Although unloaded PIHCA nanoparticles also exhibited a significant anti-leishmanial effect, the loaded nanoparticles showed a synergistic effect compared with a mixture of unloaded nanoparticles and free primaquine at equivalent concentrations.

The need for medical grade tissue adhesives both in surgery and to treat trauma has become well established. Such a device has been developed and preliminary toxicity testing completed on a compounded cyanoacrylate (Neucrylate), and its properties have been modified so it may be used as an intravascular embolic agent. Given the high incidence of iatrogenic infections in hospital, it would be desirable to have such an implantable device that inhibits dangerous bacteria.

This report analyzes the US market for Medical Adhesives and Sealants in US$ Million. The major product segments analyzed are Dental Adhesives & Sealants (Denture & Orthodontic Bonding Agents, Pit & Fissure Sealants and Luting Cements, Restorative Adhesives, Tray Adhesives, and Dental Surgical Tissue Bonding Agents), and Medical Adhesives & Sealants (Surgical/Internal Medical Adhesives & Sealants, and External Medical Adhesives & Sealants). Annual forecasts are provided for the period of 2000 through 2015.

Over the past century, synthetic adhesives have largely displaced their natural counterparts in medical applications. However, rising concerns over the environmental and toxicological effects of the solvents, monomers, and additives used in synthetic adhesives have recently led the scientific community to seek natural substitutes. Marine mussel adhesive protein is a formaldehyde-free natural adhesive that demonstrates excellent adhesion to several classes of materials, including glasses, metals, metal oxides, and polymers.

Novel methods and devices which provide enhanced mixing and application of two liquid components to form a biomaterial with minimized aerosols is achieved using air flow rates below about 1.25 liters/minute in combination with a ratio of air flow to total liquid flow of from about 150:1 up to about 1500:1. Preferably the air flow is below about 1 liter/minute and the ratio of air flow to total liquid flow is from about 200:1 to about 1200:1. The parameters are ideally suited for the spray application of components which form a surgical sealant, e.g., a fibrin sealant.