Photostability evaluation of manidipine tablets and structural determination of its photoproducts.

Manidipine (MP) is a dihydropyridine drug, which is treated for the reduction of high blood pressure. The aim of this study is to clarify the photochemical behavior of MP in the case of ultraviolet light (UV) irradiation for MP tablets (Calslot tablets). The tablets and its altered forms (powders and suspensions) were UV-irradiated using a black light, and residual amounts of active pharmaceutical ingredients (APIs) were monitored by high-performance liquid chromatography (HPLC).

Evaluation of photostability of azelnidipine tablets and structure determination of its photoproducts.

Photo-exposure has a crucial effect on the natures of photosensitive pharmaceuticals in addition to their contents in medicines through the photodegradation. Generated photoproducts might be more bioactive and contribute to the expression of adverse side effects. This study aimed to clarify the photochemical behavior of medicines of azelnidipine, which is a member of dihydropyridine antihypertensive drugs, by the evaluation of its photostability and the determination of chemical structures of generated photoproducts.

Structure Determination of Felodipine Photoproducts in UV-Irradiated Medicines Using ESI-LC/MS/MS.

Dihydropyridine drugs are well known as photodegradable pharmaceuticals. Herein, we evaluate the photostability of felodipine (FL) medicine (Splendil (SPL) tablets) and its altered forms (powders and suspensions). FL is a type of dihydropyridine drug, but its photochemical behavior is unknown.

Identification of allergens for food-dependent exercise-induced anaphylaxis to shrimp.

Shrimp is a causative food that elicits food-dependent exercise-induced anaphylaxis (FDEIA). In this study, we sought to identify IgE-binding allergens in patients with shrimp-FDEIA. Sera were obtained from eight patients with shrimp-FDEIA and two healthy control subjects.

Photoprotective Effects of Selected Amino Acids on Naproxen Photodegradation in Aqueous Media.

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.

Protective Effect of Selected Antioxidants on Naproxen Photodegradation in Aqueous Media.

A photostabilization strategy is an important aspect of quality assurance for photosensitive compounds. This study focused on the photoprotective effects of selected antioxidants including the effect of L-ascorbic acid (AA) on naproxen (NX) photodegradation in aqueous media. NX degradation during ultraviolet light (UV) irradiation and the protective effects of selected antioxidants were monitored by high-performance liquid chromatography (HPLC).