Hydrogels have plenty of uses. They are utilized to provide hygiene products, produces contact lenses and used to dress wounds. There are multiple patents of hydrogels. However, very few can be found in the market. Commercial uses of hydrogels include tissue engineering and drug delivery. Nevertheless, advances are being made primarily in tissue engineering.
Over the years, hydrogels have become so popular. Their spectacular properties which include softness, high water content, biocompatibility, and flexibility have amused many health professionals. Synthetic and natural hydrophilic polymers can successfully be chemically and physically be cross-linked to come up with hydrogels.
They have a unique resemblance to living tissues. This has opened up many opportunities where it can be applied in diverse biomedical areas. Presently, hydrogels are used for hygiene products, to manufacture contact lenses, drug delivery systems, and tissue engineering scaffolds and wound dressings.
This text will provide a review of their main characters when it comes to biomedical applications. Technically, hydrogels are three dimensional, polymeric, hydrophilic networks that are capable of sucking large volumes of water or other biological fluids.
Because of their high affinity to absorb water content, soft consistency, and porosity, they effortlessly stimulate the living tissues correctly compared to other synthetic biomaterials. Medically, hydrogel uses may degrade or be chemically stable. If they degrade, they entirely disintegrate and finally dissolves.
Hydrogels are referred to as physical or reversible gels if molecular tangles or secondary forces, i.e., ionic, hydrophobic forces or H-bonding play a vital role in the formation of the network. Physical gels work entirely different. They can easily be reversed. Additionally, it’s easier to dissolve them. All that is required is to alter their environmental conditions, i.e., PH, temperature or the ionic strength of a solution.
In ‘chemical’ or’ permanent’ gels, the web of covalent bonds that joins various macromolecular chains can be attained by associating polymers in a solution or a dehydrated state. The gels will, therefore, be non-charged or charged depending on various elements, i.e., the nature of fully functional groups that are present in a structure.
Charged hydrogels exhibit their current status by swelling up while in various amounts of PH. It’s correctly known that these hydrogels can go through multiple changes specifically in shape when they are exposed to a field that is electrified.
What Are The Healing Benefits of Hydrogels?
Because hydrogels are moisturized, they provide a serene environment for the wound. This in turns initiates healing phases which include epidermis repair, granulation, and removal of the surrounding dead tissues. Additionally, they aid in the healing process. The cooling sensation provided by the hydrogel moisture offers plenty of relief as the patient never experiences much excruciating pain for at least six hours. When moisture is evenly provided on the wound bed, all manner of discomfort that may be experienced when changing the wound dressing is immensely reduced. Also, the risk of infection is also decreased.
Types Of Wounds That Can Be Treated By Using Hydrogels
There are different types of wounds that hydrogel uses can prove positive. They include;
Dehydrated or dry wounds.
Full-thickness lesions or partial lesions.
Severe scrapes or abrasions.
Minor wound burns.
Radiation skin damage.
Wounds with granulated tissue development.
Caution should be taken when using hydrogel. When the wound is exceptionally moist, or there is much exudate around the injury, hydrogel should not be applied. In most medical cases, hydrogel dressing will need a cover dressing. This is because they are challenging to secure. Also, hydrogel uses can effortlessly hydrate the injury site if they are not adequately covered.
Dressing Changes
It’s medically advisable that you change the hydrogel wound dressing at least after every four days so that you prevent the wound covering from getting too close to the wound. Changing also ensures that hydrogel doesn’t get attached to the wound site.
Primarily, you can note when it’s time to change the dressing due to the accumulation of body fluids that indicates that the injury site is receiving excessive hydration. If your hydrogel dressing is amorphous, don’t forget to rinse off any gel left over. You can use a saline solution or wound cleanser. Do this only if it’s necessary.
When getting rid of the hydrogel sheet or impregnated gauze, gently lift one of the edges up and then smoothly peel it backward. This process is critical because you are avoiding wound damage. You can soak the covering in saline solution to assist soften the bandage.
Don’t forget to implement general wound safety precautions when undressing and dressing the wound. Thoroughly wash your hands clean, put on sanitized gloves and immediately dispose of the used bandage after you take it off.
Hydrogel For Contact Lenses
A hydrogel is a biocompatible synesthetic material that is beneficial for all contact lens applications. Contact lenses are classified as soft or hard depending on their elasticity. Hard lenses are much preferred because they are long-lasting. However, they tend to be poorly accepted by wearer’s because they require a lengthier period for adaptation.
Hard contact lenses are made from hydrophobic materials that include poly-hexa-fluoroisopropyl methacrylate or poly-methacrylate. Soft contact lenses are made from hydrogels. However, soft contact lenses can be produced using different techniques. Some of these techniques include mold-casting, spin-casting, and lathe-cutting.
In-mold and in-spin casting a proportion of liquid monomer is mixed and then well placed in a concave type of optical mold so that it can give the shape of a lens. All contact lenses should be made in a manner that they can excellently get wet to prevent tear-film deposits.
The soft lens which is based on hydrogels has a greater adherence. To fit the eye properly, many lenses are being produced to enhance the fit. However, they are faced with several cons. They have non-appealing gas permeability. Also, they don’t freely allow oxygen to reach the cornea. The cornea should receive a sufficient amount of oxygen and at the correct rate.
Some soft contact lenses have been made to overcome these faults. They have been integrated with cross-linked and hydrated polymeric materials that consist of silicon and some amounts of water within their polymeric matrix.
Drug Delivery
Hydrogels have interested many in the way they can be applied to deliver drugs. They have unique physical properties that oversee drug delivery. Hydrogels are characterized by their porosity which is cross-linked to their matrix and their affinity to attract water.
Their structure which is quite porous allows drugs to be loaded and then released. The benefits offered by hydrogels for drug delivery entail the possibility for a sustained release. This in turns results in high maintenance of high local concentration of a pharmaceutical ingredient that is active for a very long period.
The intended drug can then be loaded into a hydrogel and then later slowly released. The process proceeds through some mechanisms which include; chemically controlled, swelling controlled, diffusion controlled, and environmentally –receptive release.
Tissue Engineering
Thousands of patients around the globe are suffering from the failure of various tissues and organs. The suffering is caused by accidents or due to infections and other chronic diseases. Several surgeries are conducted to replace these damaged tissues with the aim of giving the patients relief and cure.
Hydrogels have contributed to tissue engineering which has seen recent applications in health facilities successful. Mostly, hydrogels are applied as space fillings and delivery agents for all bioactive substances. They then organize cells and then present stimuli to oversee the development of a required tissue.
