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The aim of this study was to produce hydrogels for topical use and having strengthened anti-inflammatory, analgesic and antirheumatic activity. To obtain the above effect dry standardized plant extract was added to enrich a formulation containing therapeutic agent (ketoprofen) from the group of nonsteroidal anti-inflammatory drugs. Dry standardized extract from Solidago virgaurea L. of confirmed anti-inflammatory activity was selected for this purpose. The derivatives of acrylic acid polymers (Carbopol Ultrez and Carbopol 980) were used as the formulation vehicles. These vehicles were selected owing to their high applicative properties--transparency, resistance to changes of temperature, perfect tactile and esthetic qualities, no sensitizing agents, no toxicity and lack of influence on therapeutic properties of the therapeutic agent and compatibility in the pharmaceutical phase. The produced formulations were exposed to basic physicochemical tests--pH, viscosity parameters (structural viscosity, yield stress and thixotropy), pharmaceutical availability and durability after six months of storage. The effect of component plant extracts on the process of ketoprofen diffusion to acceptor fluid through a semipermeable membrane was also compared. The obtained results indicate that dry standardized extract from Solidago virgaurea L. does not affect significantly the process of ketoprofen release from the tested preparations. After six months of storage the preparations with ketoprofen demonstrate rheological stability and high pharmaceutical availability.

The study assumption was to work out a prescription for dental anti-inflammatory hydrogel on Carbopol 971P base. Dry plant extracts (sage, horsetail) and nonsteroidal anti-inflammatory drug (sodium ibuprofen) were introduced into the prescription of a model hydrogel. The aim of the study was to estimate pharmaceutical availability of the applied therapeutic agents and to test their effect on physicochemical properties of the produced form of a drug. The physicochemical parameters of the produced preparation were tested. Viscosity tests were performed using cone-plate digital rheometer. Extensometric method was used to test extensibility. pH measurements were performed by direct immersing the electrode connected with pH-meter into the hydrogel samples of uniform mass. Pharmaceutical availability of therapeutic agents contained in hydrogel (active components of plant extracts, sodium ibuprofen) was estimated. The rate of the process of mass exchange was tested by spectrophotometric method determining the quantity of therapeutic agents diffusing into acceptor fluid at the same time intervals. Sodium ibuprofen is better released from the hydrogel containing horsetail extract (815.5 c.u.) than from the hydrogel of parallel prescription containing sage extract (640.8 c.u.). Hydrogels containing dry extract from horsetail have greater extensibility and lower structural viscosity as well as the value of yield stress than equivalent hydrogels containing sage extract. Introduction of sodium ibuprofen into the prescription of hydrogels with plant extracts modifies rheological parameters (greater extensibility, lower viscosity of the preparation). The tests of the kinetics of therapeutic agents release demonstrated that the presence of sodium ibuprofen in the prescription of hydrogels exerts an influence on the decrease of the effectiveness of the release of active substances contained in these extracts.

Active components of glycol extract from thyme manifest anti-inflammatory and astringent properties which may be also used in dentistry. The assumption of this study was to work out a prescription of dental anti-inflammatory hydrogel containing nonsteroidal anti-inflammatory drug and glycol extract from thyme. The aim of this study was to assess pharmaceutical availability and physico-chemical parameters of hydrogels produced on the base of various Carbopols (974P, 971P and AA1). Pharmaceutical availability of therapeutic agents contained in the hydrogel was tested. The rate of the process of mass exchange was tested with spectrophotometric method by determining the quantity of therapeutic agents diffusing into acceptor fluid at identical time intervals. Physicochemical parameters (including viscosity) of the produced preparation were estimated dependently on the vehicle variant components (acrylic acid polymers). Viscosity tests were performed with cone-plate digital rheometer. The kinetics of volatile components from the preparation was estimated by gravimetric method. pH measurements were performed by direct immersion of the electrode connected with the pH-meter in the samples of hydrogels of the same mass. The highest pharmaceutical availability of therapeutic agents was obtained in the tests of a hydrogel with Carbopol 971P. The area under sodium ibuprofen release curve from this hydrogel was estimated as 626.06 of conventional units. The content of active components of thyme extract in the last sample collected during the test of their release was 5.2729 mg/1 cm2 of the release area. Advantageous rheological parameters as regards application such as: low value of structural viscosity (11762 mPa x s at shear rate 2.4 1/s), low value of hysteresis loop (0.51 c.u.) and yield stress (6.51 N/m2) as well as natural pH for oral cavity (6.7) were also obtained for a hydrogel with Carbopol 971P.

Rheological parameters were tested in market hydrogel products of anti-inflammatory activity. Their prescription was worked out on Carbopol base. The rate of volatile components loss from pharmaceutical preparations was estimated with gravimetric method, while their viscosity parameters (structural viscosity, yield stress, the area of hysteresis loop) were determined with cone-plate digital rheometer. The kinetics of the therapeutic agent (ketoprofen) release through a standard Viscing membrane to external compartment was tested in hydrogels in vitro. The aim of the study was to determine the relationship between rheological parameters dependent on the prescription of the tested hydrogels and pharmaceutical availability of ketoprofen. Pharmaceutical preparations of anti-inflammatory activity made on Carbopol base are non-Newtonian liquids diluted with shear. Due to ethanol content in their prescription, after application on skin, the increase of structural viscosity and the decrease of ketoprofen pharmaceutical availability accompany the process of volatile components loss from the surface layer of the preparation. Ketoprom hydrogel, having propylene glycol in its composition, is characterized by higher values of viscosity, hysteresis pool area and yield stress than Fastum preparation. Insignificant differences between experimentally determined in vitro areas under the curves of ketoprofen release are associated with rheological parameters of the investigated hydrogels, which was anticipated on the basis of Einstein-Smoluchowski's equation. Ketoprofen penetration from the tested pharmaceutical products on Carbopol base to the external compartment is in accordance with kinetics of "0" order and is diffusion-controlled.

Belonging to the classes of: Rofams, Rokopols and Rokanols were used to form the gels soap base. The model gels extensibility was investigated by extensometric method, while their viscosity parameters were determined with cone-plate digital rheometer. Regardless of the applied gel vehicle, model prescriptions of dental anti-inflammatory gels with sodium ibuprofen have been worked out. Natural polysaccharides: xanthan gum, tragacanth, guar gum were the vehicles of the formed gels. New non-ionic surfactants the most beneficial results of rheological measurements were obtained for model gels with Rofam R-15. The calculated areas under extensibility curves of preparations with Rofam R-15 are greater than for gels with Rokopol RF55 or Rokanol OC9. Introduction of Rofam R-15 into the prescription is associated with maintenance of low value of yield stress. When this value is exceeded under the effect of slight shear, the gel does not stay long on the surface of its application. High values of theoretical coefficients of sodium ibuprofen diffusion from gels with Rofam R-15, calculated from Einstein-Smoluchowski equation, are the consequence of their low viscosity. The carried out in vitro comparative testing of the kinetics of sodium ibuprofen release from the gel with Rofam R-15 and from gel with sodium estolate of parallel prescription did not demonstrate any basic differences in the size of the areas under the release curves (14,4046 and 13,5308 c.u. for the vehicle with xanthan gum).