The first contact lens was made with poly(methyl methacrylate) (PMMA ),in 1939. In the 1960s, poly 2-hydroxyethyl methacrylate (pHEMA), which takesthe form as a hydrogel in water, was introduced.1 Hydrogels arepolymers that are highly hydrophilic, allowing them to absorbs large amounts ofwater.
2 The monomers of both of these polymers contains C=C bonds,which is what allows them to polymerize, as the double bond will break. Dr. Ghatora’s primary research is todiscover a method to prevent calcification on lens implanted into patients withcataracts. A cataract is often a result of aging eye lens, and it develops acloudy film, which makes it difficult to see. The common treatment for this isto remove the cloudy lens surgically, and replace it with an artificial lensmade out of the polymer PMMA.
However, complications often arise after havingthe lens for a period of time, one of which is calcification. Calcification is thedevelopment of calcium deposits on the surface of the lens. It is exactly whythese calcium deposits form, however it is observed they are more likely tooccur in patients who are diabetic, thus it is likely that a patients personalbiochemical makeup has an effect as to whether or not calcification occurs.3Dr. Ghatora hypothesized that if the surface of the PMMA was sterilized usingfluorination (the process of treating the surface with fluorine gas), then thesurface will be more bio-compatible, and not calcify, as fluorinating a surfaceincreases its barrier properties. Dr.
Ghatora’s results were as follows: thesurface of the lens became more wettable. However, there was also a decrease inmolecular weight. Since this property has changed, it means that the lens haschanged either physically or chemically in some way. Therefore, this researchisn’t finished. Dr. Ghatora’s goal is to find a new lens that doesn’t changeduring fluorination.
Another project of Dr. Ghatora’s iscreating contact lens that release medication and ointment. Current treatmentsfor many optical conditions is eye drops, ointment, and ophthalmic suspension.
All of these are a liquid that are dropped into the eye, and are inferior for afew reasons, the biggest being that they need to be administered multiple timesduring a day, and impair vision for a few minutes after administration.Drug-laden Contact lens would fix this issue, as they have good bio-compatibility,and would administer the drug throughout the day. These contact lens would bepossible, because pHEMA is extremely hydrophilic; it can hold onto largeamounts of water.
2 If the drug was made into an aqueous solution,the pHEMA lens would be able to absorb it, and release it into the eye.