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The protective nature of the human eye makes ophthalmic medication administration extremely difficult to control. However, thanks to new technology and spectral analysis, a new form of eye medication may provide a solution. Image source: Flickr CC user Elizabeth Ellis
Drug administration is an important part of pharmaceutical effectiveness and spectrophotometry plays a vital role in the development and monitoring of various forms of prescription drugs. Pills, capsules, powder, orodispersibles, and liquid medications all utilize spectrophotometry to aid in the analysis of the APIs (active pharmaceutical ingredients), stability, and safety of these products. This one simple and effective tool spans a wide range of pharmaceutical compounds, textures, and viscosities. Current research is utilizing this technology to lead the pharma industry towards new horizons.
One main research area and need for growth has to do with the effectiveness of ophthalmic medications. Medications for the eyes remain difficult to administer effectively. “Conventional ophthalmic solutions frequently show poor bioavailability and a weak therapeutic response because they are often eliminated before they can reach the cornea, when patients blink or their eyes tear.”1 This greatly reduces the effectiveness of these medications, making proper dosing difficult and optimal results inconsistent. Not only do the APIs in these solutions lose their effectiveness quickly after administration, but the protective nature of the human eye efficiently removes these formulations through the tear ducts and transfers this medication to other unaffected areas of the body. This can inadvertently affect the gastrointestinal track leading to adverse responses that might otherwise be avoided.
Finding a New Solution
Various kinds of ophthalmic medications are used to treat diseases of the eye, but the effectiveness wears off rapidly once surface contact is induced. Whether medication is in the form of eye drop, ointment, or capsule, studies show that drug concentration diminishes rapidly within minutes of administration. New advancements in ophthalmic solutions have led to the development of formulations that convert to a gel-type substance once contact is made with the surface of the eye. As these solutions change in viscosity, continual monitoring must be used to confirm that drug effectiveness and uniformity prevails throughout these changes.
UV spectrophotometry is a simple way to continuously monitor these changes and is already used for a variety of applications in the pharmaceutical industry. To ensure that gelatinous ophthalmic solutions maintain drug content uniformity, it is necessary to quantify the concentration of active ingredients throughout the suspension.2 UV spectrophotometers use absorption rates to quantify these concentrations and provide continual data and feedback on uniformity and changes that are otherwise unobservable through visual inspection. Determination of these ingredients can then be given as numerical data for consistency and repeatability testing.
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UV spectrophotometers use light absorption measurements to quantify the concentration and uniformity of ophthalmic solutions. Image Source: Flickr CC user peasap