Pharmacotechnical and structural-mechanical characterization of hydrogels with thienoflogin

Abstract

The aim of this study was to investigate the organoleptic, pharmacotechnical, and structural-mechanical properties of Thienoflogin-containing hydrogels, as well as the effect of excipients on their rheological characteristics. Materials and Methods. The objects of the study were experimental hydrogel samples with different concentrations of Aristoflex AVC, containing either a dispersion of Thienoflogin in vaseline oil with the addition of polysorbate 80 or a dispersion of Thienoflogin in dimethyl sulfoxide. The appearance and homogeneity of the experimental samples were evaluated; colloidal stability and thermostability were assessed, and the pH of the model samples was measured. Based on measurements of structural and mechanical parameters (shear stress and dynamic viscosity), flow rheograms were constructed, and the dependence of structural viscosity on shear stress was investigated. Results. The rational combination of Thienoflogin with the gel formulation is supported by previous studies on release kinetics using the diffusion method across a semipermeable membrane. Hydrogels using excipients of different natures and properties were studied, and the optimal hydrogel composition with the best Thienoflogin release and its subsequent effective application was determined. The results of the research indicate that all experimental samples have homogeneous consistency, and their pH ranges from 5.4 to 6.1. The samples are thermostable and colloidally stable. Based on the study of the structural and mechanical properties of the experimental samples, graphs of the dependence of dynamic viscosity on shear rate were constructed. It was established that the dynamic viscosity decreases with increasing shear rate, indicating pseudoplastic behavior of the experimental samples and the disruption of the hydrogel’s internal structure under applied stress. The presence of hysteresis loops on the flow rheograms indicates sufficient thixotropy of the studied samples, allowing the gel structure to gradually recover after disruption. Experimental samples were selected that showed good consumer properties: they spread evenly on the skin surface and did not leave marks on clothing. Conclusions. The organoleptic and rheological properties of hydrogels containing Thienoflogin were studied. It was established that the developed samples exhibit non-Newtonian flow behavior and moderate thixotropic properties. It was found that the Thienoflogin hydrogel based on the gelling agent Aristoflex AVC at a concentration of 1.5 % demonstrates satisfactory quality parameters and consumer characteristics.