The physicochemical properties, especially pH value of dental medicines, have significant influence on the health of oral cavity tissues. The pH of formulations should correspond to the value of saliva pH (5.5–8.0). For carbomer-based gels, the required pH value is obtained by neutralizing them with alkaline components, which leads to their structuring (thickening). This affects the physical properties of the gel, its residence time at the application site and the rate of release of active pharmaceutical ingredient. Therefore, the main purpose of this study is to evaluate the rheological, textural, and biopharmaceutical properties of Carbomer Polacril^® 40P-based dental gel depending on the pH value. Evaluation of the rheological properties of gel preparations were performed by measuring the structural viscosity of the samples as a function of pH and temperature. The textural properties of the gel were evaluated by performing tests regarding back extrusion and spreadability. Carbomer Polacril^® 40P-based gels haven’t shown noticeable thixotropic behavior, and were characterized by plastic flow in the whole studied pH range. The structural viscosity at the selected average pH value hasn’t differed at storage (25 °C) and application (37 °C) temperature. Texture studies of dental gels have shown a strong correlation with rheoparameters. Their rheological behavior and textural properties haven’t changed significantly between the pH range of 5.5–6.6. The relatively narrow range of working pH values does not affect the change in the viscosity of the preparation significantly and, consequently, does not affect the release of APIs from the developed Carbomer Polacril^® 40P-based dental gel.

This study aimed at evaluating the impact of environmental factors on the accumulation of various components in Hedera helix L. folium collected from different European countries. The obtained results of studied samples showed that the antioxidant capacities were in the range of 0.027 to 0.688 mg/g. Contents of active components varied: phenolic acids – from 0.033 up to 2.92 gallic acid equivalents mg/g, flavonoids – from 0.031 to 0.281 mg/g and hederacoside C − 13.54–109.458 mg g⁻¹ DW. Samples from the northern countries had higher amounts of all phytochemicals in comparison to the southern ones. Among all studied parameters, the duration of sunshine, soil and climate had the most significant influence on the accumulation of components in ivy raw materials while altitude and precipitations showed none impact. Hedera helix can be considered as an excellent source of triterpene saponins, flavonoids and phenolic acids, and growing it at the right conditions may significantly enhance the quality of its raw material for medicinal purposes. Graphical Abstract

Developed methods for routine analysis of medicines should be considered in terms of analytical efficiency, economic cost, as well as their environmental impact. Different chromatographic methods for the routine quantitative analysis of hederacoside C in ivy leaf extract and its original dosage forms (capsules and syrup) are developed. The performance of HPLC and UPLC methods should be done using ACE C18 (150 mm × 4.6 mm, 5.0 μm) and ACQUITY UPLC BEH C18 (50 mm × 2.1 mm, 1.7 μm) columns, respectively, and both of them require a mixture of water and acetonitrile in the ratio 71/29 as a mobile phase. The HPTLC procedure is carried out using the stationary phase pre-coated silica gel 60 F₂₅₄ glass sheets and a mixture of anhydrous formic acid/acetone/methanol/ethyl acetate (4:20:20:30 v/v). The most suitable conditions of preparation for each sample are established, for instance, the solid-phase extraction (SPE) for the analysis of syrup is applied. Analytical methods are compered by analytical accuracy, calculation of expenses, and assessment of their influence on ecology. All methods are recognized as accurate, precise, and reliable. However, the assessment of the environmental impact shows that HPTLC is the less green method. On the another hand, it is found to be the cheapest, the costs of performing HPTLC are 2.3 and 1.6 times lower than for HPLC and UPLC, respectively.

AIM: Tetracycline hydrochloride is one of the most popular antibiotics, which are used in the manufac­turing of finished pharmaceutical products and compounded medicines. The aim of our work is develop­ment and validation of the assay method for tetracycline hydrochloride determination in the combined compounded ointment. MATERIALS AND METHODS: The assay is proposed to be carried out by spectrophotometric method. RESULTS AND CONCLUSIONS: A spectrophotometric method for tetracycline hydrochloride determi­nation in compounded ointment was developed. For this method the following validation characteristics were studied: stability, selectivity, repeatability, precision, accuracy, reproducibility. We found that all met­rological characteristics are not higher than the validation criteria. Stability of test solutions was observed for 60 minutes, which allows using this method for tetracycline hydrochloride quantitative determination in studied ointment.

One of the main steps in the pharmaceutical development of drugs is the choice of quality control methods. The correctness of the method must be confirmed by validation. In addition, manufacturers take into account various economic and environmental factors. It is especially important to determine the above aspects for domestic and promising drugs, such as the morpholinium thiazotate. The aim. During the development of methods for the routine analysis of medicinal products, attention should be paid to efficiency of analysis, budget, as well as their impact to the environment. Because of this reason, not only new methods for routine analysis should be developed. It is important this methods must be environmentally-friendly and cost-efficient. Materials and methods. The determination of the morpholinium thiazotate was carried out by HPLC using the SunFire C18 (150 mm × 4,6 mm, 5,0 μm) and gas chromatography with a flame ionization detector using the Rxi-5 ms (30 m long, 0.25 mm outer diameter and 0.25 μm liquid stationary phase thickness). Results. Various chromatographic methods for the routine quantitative analysis of morpholinium thiazotate were developed. The most suitable conditions for sample preparation were established. Proposed methods were compared to find the most ecological and economic. Conclusions. Proposed methods were accurate and reliable. However, an environmental impact assessment showed that GC-FID is a more environmentally friendly and economical method of analysis. Using 12 Principles of green analytical chemistry, the overall “analytical GREEnness (AGREE)” scale for the proposed analytical approach was computed 0.72, showing the good greener nature of the proposed analytical approach

Objectives: The aim of this study was the development a new, fully validated high performance liquid chromatography (HPLC) method for the quantitative analysis of secoiridoid glycosides by an active marker swertiamarin in the herb Centaurium erythroeo Rafn. The article describes a new approach to the standardization of C. erythraea and more specifically the development of a new validated HPLC method for the quantitative determination of secoiridoid glycosides by swertiamarin. Materials and Methods: The quantitative determination of swertiamarin was performed in isocratic mode on a Symmetry C18 column using water and acetonitrile as solvents for the mobile phase. Results: Validation characteristics of the developed method showed that it was linear in the whole range of concentrations from 0.01 mg/mL to 0.05 mg/mL swertiamarin. All validation characteristics met the established acceptance criteria. Conclusion: This method can be used in the standardization of raw materials, as well as in the analysis of medicinal products and dietary supplements that include C. erythraea. The established chromatographic method was successfully applied for the analysis of raw materials of C. erythraea with the quantitative content determination of swertiamarin in the analyzed samples.