Abstract
It is important to develop a photostabilization strategy to ensure the quality of photosensitive compounds, including pharmaceuticals. This study focused on the protective effects of 20 amino acids on the photodegradation of naproxen (NX), a photosensitive pharmaceutical, to clarify the important nature of a good photostabilizer. Our previous report indicated the photodegradability of NX and the protective effects of some antioxidants on its photodegradation, therefore, this compound was used as a model compound. The degradation of NX in aqueous media during ultraviolet light (UV) irradiation and the protective effects of selected amino acids were monitored through high-performance liquid chromatography (HPLC), equipped with a reverse-phase column. Addition of cysteine, tryptophan, and tyrosine induced the significant suppression of NX photodegradation after UV irradiation for 3 h (residual amount of NX; 15.35%, 6.82%, and 15.64%, respectively). Evaluation of the antioxidative activity and UV absorption spectrum showed that cysteine suppressed NX degradation through its antioxidative ability, while tryptophan and tyrosine suppressed it through their UV filtering ability. Furthermore, three amino acids at higher concentrations (more than 100 µmol/L) showed more protective effects on NX photodegradation. For 10 mmol/L, residual amounts of NX with cysteine, tryptophan, and tyrosine were 58.51%, 69.34%, and 82.40%, respectively. These results showed the importance of both photoprotective potencies (antioxidative potency and UV filtering potency) and stability to UV irradiation for a good photostabilizer of photosensitive pharmaceuticals.
Highlights
Pharmaceuticals have been used by humans and livestock for the purpose of prevention or treatment of various diseases, all over the world
The concept of photostabilization is important for the safe use of pharmaceuticals, which tended to be degradable by photo-irradiation
The photoprotective effects of selected amino acids for NX photodegradation were evaluated to clarify their effectiveness as a photostabilizer
Summary
Pharmaceuticals have been used by humans and livestock for the purpose of prevention or treatment of various diseases, all over the world. It is well-known that ultraviolet light (UV) irradiation, which is present in sunlight, provokes the loss of beneficial effects and the gain of adverse effects for photosensitive pharmaceuticals [1,2,3]. The variety of photochemical reaction and their output as photoproducts is dependent on the variety of the chemical structure of UV-irradiated compounds and the wavelength of the UV. In the case of naproxen (NX), which is a non-steroidal anti-inflammatory drug (NSAIDs), the active compound in the tablet, its powder, and suspension was degraded by UV irradiation [5]. This report suggests that photo-degradability of pharmaceuticals is a major determinant of their quality and quantity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
