Introduction
Composition of ...
Natural sutures
Synthetic sutures
Coatings
Main Chemicals, Compounds, Components
Catgut is the main component in the natural type of dissolvable sutures. It comes from the dried, twisted intestines of animals, mainly from sheep intestines. The part of the intestines that is used is the collagen which is an abundant protein in the body that is found in places like our bones,tendons, muscles and skin. It is important because it holds our bodies together as well as gives us structure. In the making of the catgut sutures the collagen is cut and cleaned. Once the catgut is purified they twist the strips together to insure a tough single strand. Lastly they sterilize the catgut strand with a sterilizing solution that is a combination of distilled water, isopropyl alcohol and ethylene oxide.
Polyglycolic acid (PGA) or polyglycolide is one of many types of plastic that make up synthetic sutures. This plastic differed from the other because, up until 1962 it did not have many uses, that was until it was used to make one of the first synthetic sutures. It’s chemical formula is (C2H2O2 )n. It is a biodegradable polymer that has a high melting point but does not have a boiling point. There are many different ways polyglycolic acid can be obtained and depending on which method you use to make polyglycolic acid the products molecular weight could vary.
Chemistry's Role
Chemistry plays a major role in the breakdown of dissolvable sutures. Natural and manmade sutures will appear as a foreign substance to the body and that is why the body attacks the sutures, therefore dissolving them. Depending on which type of sutures are being used, natural or man made the chemistry behind it differs. If natural sutures like catgut are being used in the body then it will be dissolved or absorbed by enzymatic degradation. Enzymatic degradation is a process where proteolytic enzymes that are usually found in the digestive tract dissolve the natural suture.These enzymes can also be referred to as peptidase, proteinase, or protease. The enzyme is separated into two different groups endopeptidase, and exopeptidase. The endopeptidase will break down the inside of the protein while the exopeptidase breaks down the outer ends of the protein. They work together to break the protein down into an amino acid.
Synthetic sutures such as polyglycolic acid are broken down in the body by a process called hydrolysis. Hydrolysis means “to split by water”, it got its name because of how water and enzymatic catalyst work together to break down the sutures. In the process of hydrolysis the body breaks polymers down to monomers. Basically the opposite of dehydration, where monomers turn into polymers and form water. The polymer is broken into two parts, then there is the factor of whether or not the polymers can be ionized or broken down into ions. If the polymer can be ionized then one part will gain an oxygen as well as a negative charge, while the other part will gain two hydrogen(H+) atoms and a positive charge. On the other hand if the polymer cannot be broken down into ions then one part gains a hydrogen(H+) atom and the other will gain a hydroxide(OH-) ion.
Background Research
Sutures have been used for thousands of years, it has been discovered that even ancient Egyptians used them for medical purposes. Dissolvable sutures are used for inside the body, whereas non dissolvable sutures are used on the outside of the body and are eventually removed. Sutures have different thicknesses,elasticity and decomposition rates, which help the sutures adjust to different kinds of lacerations. Sutures range in sizes from 11-0 to 7 and are usually attached to a curved needle.There are braided sutures, and chromic sutures which are single stranded. When in the body the dissolvable sutures must be taken care of, they will itch but itching them may ruin them, and by staying away from dirt, mud or anything that could get in the wound and infect it. Signs to look for when checking if the wound with sutures is infected would include bleeding, swelling,or pus coming from the wound itself. Other signs would be a bad odor or a red appearance coming from around the wound, and an increase of pain from the area. It is important to check in with your doctor if any of these symptoms occur.
Resources
http://science.howstuffworks.com/innovation/everyday-innovations/question611.htm
https://en.wikipedia.org/wiki/Surgical_suture#Materials
http://www.surgisolution.com/blog/difference-between-absorbable-and-non-absorbable-surgical-sutures/
http://www.madehow.com/Volume-7/Suture.html
http://www.upstate.edu/surgery/pdf/education/clerkship/suture_types.pdf
http://www.just-health.net/Dissolvable-Stitches.html
http://www.medicalnewstoday.com/articles/262881.php
https://en.wikipedia.org/wiki/PLGA
https://en.wikipedia.org/wiki/Polydioxanone
https://en.wikipedia.org/wiki/Lactic_acid
https://en.wikipedia.org/wiki/Glycolic_acid
https://en.wikipedia.org/wiki/Polyglycolide
https://en.wikipedia.org/wiki/Catgut_suture
http://pubchem.ncbi.nlm.nih.gov/compound/71391
http://pubchem.ncbi.nlm.nih.gov/compound/65431#section=Top
http://pubchem.ncbi.nlm.nih.gov/compound/18233
http://pubchem.ncbi.nlm.nih.gov/compound/Poloxamer_188
http://www.britannica.com/science/proteolytic-enzyme
https://en.wikipedia.org/wiki/Cellulose
About the Author
April Zimmerman is a junior at Billings Senior High. She is a member of the Billings Senior High tennis team as well as the orchestra. She also has a part time job at a local veterinary clinic. In her free time she enjoys hanging out with friends, watching tv, and spending time with her dog.