Polymeric gels for drug delivery

Published on May 30, 2022   14 min

Other Talks in the Series: Drug Delivery

Hello, I am Dora Safar from the School of Medicine at the Royal College of Surgeons in Ireland. I am attached to the Soft Matter Research Group at the Royal College of Surgeons in Ireland. This is led by Dr. Roshan Deen. The main focus of the research group is to develop new types of hydrogels for biomedical applications. My research interest is in developing new types of hydrogels for drug delivery and tissue engineering applications. In this lecture, I will be presenting a review of polymeric gels for drug delivery. I will be presenting a variety of polymeric gels that are used for controlled drug delivery and I will highlight some of the main examples.
The outline of this lecture will be the following. We will start with hydrogels and properties, then we will move on to the classification of hydrogels. Then I will talk about the swelling of hydrogels and the types of water that are present in swollen gels. After this, we will look at some major drug delivery systems. This will be followed by the medical applications of a few hydrogels.
By definition, hydrogels are crosslinked polymeric materials that can absorb large amounts of water or any physiological fluids. For any controlled drug delivery application, this swelling is the fundamental property. For a material to be considered a hydrogel, it should contain at least 10% of water by weight or by volume. When the water content is more than 95%, the hydrogel is called a superabsorbent hydrogel. The most common example of a superabsorbent is baby diapers. A thin layer of a hydrogel is used in baby diapers to absorb large amounts of liquid. The structural integrity of the swollen hydrogel is maintained by either a physical crosslinking or a chemical crosslinking. The physical crosslinking is non-permanent, whereas the chemical crosslinking is permanent. The figure shown illustrates that when you take a dry hydrogel and place it in water, the hydrogel absorbs the water and swells, becoming rubbery in nature. The blue spheres represent the water molecules within the swollen hydrogel.