Anna Zgadzaj

Evaluation of photodegradation, phototoxicity and photogenotoxicity of ofloxacin in ointments with sunscreens and in solutions.

Fluoroquinolones are widely used anti-bacterial agents that are known to exhibit moderate to severe phototoxicity. Furthermore some of them reveal photogenotoxicity under UV irradiation. Incidence of side effects due to light exposure may be augmented, if the medicament is used topically. The main goal of this work was to compare the extent of photodegradation of ofloxacin in ointments with various excipients: hydrated or non-hydrated base and the addition of sunscreens: bisoctrizole (Tinosorb M) and bemotrizinol (Tinosorb S). The next goal of present work was the analysis of phototoxicity and photogenotoxicity of ofloxacin photodegradation products in tested ointments and in solutions with the umu-test, the test of mitotic gene conversion with Saccharomyces cerevisiae D7 and the micronucleus assay with V79 Chinese hamster cell line. At the same time an attempt was made to determinate the photodegradation products of ofloxacin in different unguents variants. We observed a significant photoprotective effect in ointment with Tinosorb M. We did not evaluated relevant differences regarding the genotoxicity and toxicity of unguents. However, the pre-irradiated ofloxacin solutions in comparison to samples stored in the dark were significantly more genotoxic to bacteria, slightly increased the number of micronuclei in V79 cell line and were toxic to the yeast strain.

A Novel Delivery System for the Controlled Release of Antimicrobial Peptides: Citropin 1.1 and Temporin A

Antimicrobial peptides (AMPs) are prospective therapeutic options for treating multiple-strain infections. However, clinical and commercial development of AMPs has some limitations due to their limited stability, low bioavailability, and potential hemotoxicity. The purpose of this study was to develop new polymeric carriers as highly controlled release devices for amphibian peptides citropin 1.1 (CIT) and temporin A (TEMP). The release rate of the active pharmaceutical ingredients (APIs) was strongly dependent on the API characteristics and the matrix microstructure. In the current work, we investigated the effect of the polymer microstructure on in vitro release kinetics of AMPs. Non-contact laser profilometry, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC) were used to determine the structural changes during matrix degradation. Moreover, geno- and cytotoxicity of the synthesized new carriers were evaluated. The in vitro release study of AMPs from the obtained non-toxic matrices shows that peptides were released with near-zero-order kinetics. The peptide “burst release” effect was not observed. New devices have reached the therapeutic concentration of AMPs within 24 h and maintained it for 28 days. Hence, our results suggest that these polymeric devices could be potentially used as therapeutic options for the treatment of local infections.

Development of photoprotective, antiphototoxic, and antiphotogenotoxic formulations of ocular drugs with fluoroquinolones

The development of innovative solutions in photosafety of photolabile pharmaceutical products may help to reduce the adverse effects of these products, caused by light exposure. Providing new data in this area of study is particularly important in case of drugs applied topically on sensitive organs such as eyes. The main goal of this research is to investigate whether two potential excipients, namely: p-coumaric acid and benzophenone-4, affect the photodegradation, phototoxicity and photogenotoxicity of water solutions of four fluoroquinolones: ciprofloxacin, lomefloxacin, fleroxacin and clinafloxacin. We conducted a set of bioassays combined with the application of high-performance liquid chromatography and mass spectrometry techniques. The significant reduction of phototoxic and photogenotoxic abilities was evaluated in mixtures with ciprofloxacin and p-coumaric acid by using the umu test with Salmonella typhimurium TA1535/pSK1002, the methylthiazol tetrazolium reduction assay, and the micronucleus assay with the V79 cell line. In the bacterial assay the opposite effect was observed for the formulation with lomefloxacin and p-coumaric acid. This may be explained by the significant differences in the profile of the lomefloxacin photodegradation products. Further, the photoprotective and antiphotomutagenic abilities of ciprofloxacin mixed with benzophenone-4 were assessed. Promising results obtained in compositions with ciprofloxacin may be a basis for further research. Nevertheless, the increase in the DNA damage potential in mixtures with p-coumaric acid and two other antibiotics shows the importance of the safety evaluation of such innovative combinations.

An alternative approach to controlled release of oxprenolol from the implantable delivery system based on biodegradable copolymer and genistein

ABSTRACT This paper describes the development of covalent star-shaped poly(L-lactide/ϵ-caprolactone) random copolymer-oxprenolol (OXP) conjugates as a potential approach to controlling drug release from implantable delivery systems. We prepared synthesized materials containing 14–17 mol% OXP, which were conjugated via an ester bond. The conjugates, which were composed of biodegradable copolyester chains, natural genistein as a central core and drug, were characterized by hydrogen nuclear magnetic resonance (1H-NMR), Fourier transform infrared spectroscopy (FTIR) and viscosity methods. We evaluated the cyto- and genotoxicity of the synthesized copolymeric matrices, followed by the conjugates, with bacterial luminescence, protozoan and Salmonella typhimurium TA1535 assays. Furthermore, we performed in vitro mammalian assays of the obtained products with V79 cells. We found that the in vitro release of OXP from the obtained star-shaped conjugates was dependent on the structure of the synthesized biodegradable matrices.