Illness is an indispensable part of life. Humans have forever attempted to relieve one another of the onerousness that accompanies sickness. And predictably enough, history has witnessed huge leaps in the f1eld of medicine which today branches out to innumerable sub-f1elds. Although technological advancements have occurred, the fundamental purpose of medical research remains unaltered – developing drugs that actively f1ght against the symptoms or cause of illness.
Administration of a drug, drug delivery, can have various routes – oral intake, or by inhalation among others. But most of these routes pose the challenge of drug-degradation in the path before reaching the desired target. To counter this, many drugs are directly injected into the body at the exact location. These drugs, injectables, form a major component of the changing face of medicine. It is notable that as in the case of many other f1elds, polymers play a major role in this area too. Polymeric materials are preferred because of the immense control one has over the physical and chemical properties by varying molecular synthesis processes.
Ongoing research at the Polymer Engineering Group at the Department of Chemical Engineering, liT Madras focusses on the study and development of reinforced natural and synthetic materials (f1bre gels) for such use.
The technique of using injectables has been around for quite some time now, with a major success story being that of viscosupplementation, a proposed medication for arthritis. Pain caused due to osteoarthritis can be countered using anti-inflammatory drugs. But these provide only a temporary solution and some patients have adverse reactions to such medication. Direct injection of a preparation hyaluronic acid (the substance whose low concentrations in the knee-joints causes the condition) lubricates the joints and relieves the patient of pain. Though the long-term effectiveness of the above procedure is still an active area of research, it seems like the best choice to patients whose bodies do not react positively to non-medical measures or analgesics.
Similar medication/cures have been proposed for many other ailments and the list is only growing longer by the day. Many researchers have tried mimicking the natural fluids present within the human body by synthesizing composites. These composites consist of a homogenous “matrix” component which is reinforced by an f1brous component, generally thicker and stronger. There is a necessity to introduce synthetic polymer-based gels because these provide significant advantages over natural polymers. Firstly, natural polymers are difficult to store or process. And second, mechanical properties of natural polymers cannot be considered even to be of close competition to those of synthetic gels. This is because mechanical properties of the latter can be altered based on requirement and convenience due to reinforcement. Says Jagadeesh Kodavaty, a Ph.D. student and member of the Polymer Engineering Group, “[Hence] the goal is to synthesize a polymer to assist in the drug-delivery system which is both stable and has desirable mechanical properties.”
“The current work here involves the study of reinforced natural and synthetic f1bre gels for clinical applications and to characterise these materials using techniques from rheology,” he adds. Rheology is a branch of physics that deals with the flow and change of shape of matter, especially liquids. It is adopted when the material under study (f1bre gels in this case) exhibits elastic, viscous and plastic behaviour.
“More specifically, I am working on mimicking the vitreous fluid (found in the eye) using hyaluronic acid reinforced with collagen type II f1bres, with the addition of a synthetic polymer poly-vinyl alcohol and characterizing this complex system using rheology. As there is data available for the natural vitreous fluid obtained from the eye (generally animals) in the literature, I will compare my results with the same,” says Jagadeesh.
If successful, it’s only a matter of time before Jagadeesh’s efforts open up new avenues for the medical f1eld to explore. He continues to explain that as in the case of osteoarthritis, a reliable mimicked specimen and further improvisations to it could lead to a variety of medications for glaucoma, retinal repairs and many other ailments of the human eye.