''n''-Butyl cyanoacrylate (n-BCA, NBCA), a

cyanoacrylate Cyanoacrylates are a family of strong fast-acting adhesives with industrial, medical, and household uses. They are derived from ethyl cyanoacrylate and related esters. The cyanoacrylate group in the monomer rapidly polymerizes in the presence ...

ester In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

, is a

butyl In organic chemistry, butyl is a four-carbon alkyl radical or substituent group with general chemical formula , derived from either of the two isomers (''n''-butane and isobutane) of butane. The isomer ''n''-butane can connect in two ways, giv ...

of 2-cyano-2-propenoic acid. It is a colorless liquid with a sharp, irritating odor. It is insoluble in water. Its chief use is as the main component of medical cyanoacrylate glues. It can be encountered under various

trade name A trade name, trading name, or business name is a pseudonym used by companies that do not operate under their registered company name. The term for this type of alternative name is fictitious business name. Registering the fictitious name with ...

s, e.g. Cutseal, MediBond, MediCryl, PeriAcryl, GluStitch, Topocryl, Gesika, VetGlu, Vetbond, LiquiVet, Indermil, LiquiBand, Histoacryl, IFABond, CutisSeal and others. The generic international nonproprietary name (INN) for NBCA is enbucrilate. In medical and veterinary applications, NBCA, isobutyl cyanoacrylate, and octyl cyanoacrylate are commonly used. They are

bacteriostatic A bacteriostatic agent or bacteriostat, abbreviated Bstatic, is a biological or chemical agent that stops bacteria from reproducing, while not necessarily killing them otherwise. Depending on their application, bacteriostatic antibiotics, disinfec ...

and their use is usually painless. Butyl esters provide stronger bond, but are rigid. Octyl esters, while providing weaker bond, are more flexible. Blends of octyl cyanoacrylate and n-butyl cyanoacrylate are available (such as GLUture) which offer both flexibility and a strong bond. n-Butyl cyanoacrylate is also used for embolization of cerebral arteriovenous malformations before their surgical treatment. NBCA in monomer form is soluble in

acetone Acetone (2-propanone or dimethyl ketone) is an organic compound with the chemical formula, formula . It is the simplest and smallest ketone (). It is a colorless, highly Volatile organic compound, volatile, and flammable liquid with a charact ...

methyl ethyl ketone Butanone, also known as methyl ethyl ketone (MEK) or ethyl methyl ketone, is an organic compound with the formula CH3C(O)CH2CH3. This colorless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large s ...

nitromethane Nitromethane, sometimes shortened to simply "nitro", is an organic compound with the chemical formula . It is the simplest organic nitro compound. It is a polar liquid commonly used as a solvent in a variety of industrial applications such as in ...

, and

methylene chloride Dichloromethane (DCM, methylene chloride, or methylene bichloride) is an organochlorine compound with the formula . This colorless, volatile liquid with a chloroform-like, sweet odor is widely used as a solvent. Although it is not miscible with ...

. It polymerizes rapidly in presence of ionic substances such as moisture, blood, or tissue fluids. NBCA has unique properties compared to other cyanoacrylates such as octyl cyanoacrylate or isoamyl cyanoacrylate. The polymerized form has excellent tensile strength and is very effective in closing surgical or wound incisions. The closure of the wound or cut is quick (about 30 to 45 seconds) and the product has inherently some valuable bacteriostatic properties. The cosmetic outcome of the closure is comparable or generally better than an equivalent suture substitute with least amount of scarring visible after three to six months. Also important is the degradation properties of polymerized NBCA within the body. This property of NBCA has made it a very useful polymer to create various nanoparticles for delivery of drugs into the body with sustained release profiles. Heating to higher temperatures causes

pyrolysis Pyrolysis is a process involving the Bond cleavage, separation of covalent bonds in organic matter by thermal decomposition within an Chemically inert, inert environment without oxygen. Etymology The word ''pyrolysis'' is coined from the Gree ...

and depolymerization of the cured glue, producing gaseous products strongly irritating to lungs and eyes.

Medical applications

The medical applications of butyl cyanoacrylate include its use as an adhesive for

laceration A wound is any disruption of or damage to living tissue, such as skin, mucous membranes, or organs. Wounds can either be the sudden result of direct trauma (mechanical, thermal, chemical), or can develop slowly over time due to underlying diseas ...

s of the skin, and in the treatment of bleeding from vascular structures. Butyl cyanoacrylate has been used to treat

arteriovenous malformation An arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. Usually congenital, this vascular anomaly is widely known because of its occurrence in the central nervous system (usually ...

s by application of the glue into the abnormality through

angiography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perfo ...

. In gastroenterology, butyl cyanoacrylate is used to treat bleeding

gastric varices Gastric varices are dilated submucosal veins in the lining of the stomach, which can be a life-threatening cause of bleeding in the upper gastrointestinal tract. They are most commonly found in patients with portal hypertension, or elevated p ...

, which are dilated

vein Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and feta ...

s that occur in the setting of liver

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, chronic liver failure or chronic hepatic failure and end-stage liver disease, is a chronic condition of the liver in which the normal functioning tissue, or parenchyma, is replaced ...

thrombosis Thrombosis () is the formation of a Thrombus, blood clot inside a blood vessel, obstructing the flow of blood through the circulatory system. When a blood vessel (a vein or an artery) is injured, the body uses platelets (thrombocytes) and fib ...

of the

splenic vein In human anatomy, the splenic vein (formerly the lienal vein) is a blood vessel that drains blood from the spleen, the stomach fundus and part of the pancreas. It is part of the hepatic portal system. Structure The splenic vein is formed from ...

. The gastric varices are accessed by

endoscopy An endoscopy is a procedure used in medicine to look inside the body. The endoscopy procedure uses an endoscope to examine the interior of a hollow organ or cavity of the body. Unlike many other medical imaging techniques, endoscopes are insert ...

, which uses a flexible fibre-optic camera to enter the stomach. They are injected with a catheter needle inserted into the varix through the endoscope. Other sites of varices, including

esophageal varices Esophageal varices are extremely Vasodilation, dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendenc ...

, duodenal varices and colonic varices. Gastric varices have also been obliterated with recurrent injection treatment with butyl cyanoacrylate.

References

{{reflist, 2 Cyanoacrylate esters Monomers Butyl esters

Medical applications

See also

References