The Influence of UV Radiation on the Degradation of Pharmaceutical Formulations Containing Quercetin

Abstract

The aim of this study was to assess the photostability of quercetin in the presence of anionic and nonionic polymeric gels with varied compositions of an added component—glycerol. The samples were irradiated continuously at constant temperature. The stability of quercetin in solution and incorporated into the gels was evaluated by an UV-Vis spectrophotometer. FTIR spectroscopy (Fourier-transform infrared spectroscopy) was used to detect the changes in the structure of quercetin depending on the polymer used in the gel, and on the exposure time. Photostabilization is an important aspect of quality assurance in photosensitive compounds. The decomposition rate of quercetin in the ionic preparation of polyacrylic acid (PAA) with glycerol was 1.952·10−3 min−1, whereas the absence of glycerol resulted in a decay rate of 5.032·10−4 min−1. The formulation containing non-ionic methylcellulose resulted in a decomposition rate of quercetin in the range of 1.679·10−3 min−1. The decay rate of quercetin under light influence depended on the composition of the gel. It was found that the cross-linked PAA stabilized quercetin and the addition of glycerol accelerated the photodegradation.

Visualization of the photodegradation of a therapeutic drug by chemometric-assisted fluorescence spectroscopy

“…From 1 H and 13 C NMR spectral measurements, we isolated 2-chloro-N,N-dimethylcarbazole (3). Small amounts of the oxidation product of C 17 H 19 ClN 2 SO (4) and a further oxidation product of C 17 H 19 -ClN 2 SO 3 (5) were trapped, respectively. In addition, multiple coloured compounds were obtained, as conrmed by silica gel thin-layer chromatography.…”

“…[1][2][3][4] Light is one of the most serious causes of the degradation of heterocycles in the active pharmacophore of a drug. [5][6][7][8][9][10][11] This physical trigger not only reduces efficacy but also produces toxic effects brought about by the generation of photodegradation products. 12 Thus, the assessment of drug photostability is essential to ensure both proper use and patient safety.…”

Assessment of the Influence of the Selected Range of Visible Light Radiation on the Durability of the Gel with Ascorbic Acid and Its Derivative

“…For anhydrous glycerol, only the glycerol–glycerol interaction should be considered, and for glycerol–water mixtures, the glycerol–glycerol and glycerol–water interaction should be considered. It is known that in in the liquid phase, the three OH groups of the glycerol molecule can be involved in about six hydrogen bonds with of adjacent molecules, while the water molecule can establish four hydrogen bonds; however, water–water interactions were observed in the literature data even at higher glycerol concentrations because of fluctuations in density [ 30 , 31 , 32 , 33 ]. The Plackett–Burman experimental design was used to investigate the compatibility of ascorbic acid with various syrup excipients.…”

Antimicrobial and Antioxidative Activity of Newly Synthesized Peptides Absorbed into Bacterial Cellulose Carrier against Acne vulgaris

“…This combined activity may be of special importance, as C. acnes colonization leads to the formation of reactive oxygen species, including peroxide anions, which may form peroxynitrates that are responsible for the breakdown of keratinocytes [ 55 ]. This phenomenon goes in hand with the observation that endogenous, host -defense peptides [ 56 , 57 ] also have positive net charge and amphiphilicity, which are responsible for their antimicrobial activity. The performed assays confirmed a lack of cytotoxicity of P1–P6 against fibroblast lineages, which not only enhanced the applicative potential of synthetized peptides on skin surfaces, but also may be regarded as a proof of concept for the possibility of an undisturbed process of healing lesions in vivo, which is mediated by fibroblasts.…”

“…Samples of the non-irradiated peptides 1–6 were evaluated at the beginning of the experiment, and after every six hours the during 24 h of the irradiation process, presented below. The samples were irradiated with a home-built system consisting of a high-pressure mercury lamp HBO 200DC of 200 W (Osram, Munich, Germany), and cuvette-enabling safe sample processing [ 57 ]. The measurements were carried out at a constant temperature, maintained in the irradiation system.…”