Topical drug delivery in skin diseases provides a non-invasive, direct application of treatments to the affected area and avoids systemic toxicity. Quercetin is a natural polyphenol with documented activity to alleviate the symptoms of many skin diseases. The objective of this study was to prepare and assess the physicochemical properties of hydrogels made of sodium alginate (SA) and cellulose derivatives (methyl cellulose (MC) and carboxymethyl cellulose (CMC)), containing different concentrations of quercetin (0.4 and 0.7%). The physicochemical evaluation of the obtained hydrogels included organoleptic evaluation, texture analysis, spreadability, rheological properties, pH, and stability. Among the prepared formulations, MC-based gels had the highest viscosity, adhesiveness, cohesiveness, and stickiness. The results of this study indicate that MC-based hydrogels were superior to CMC- or SA-based gels in their ability to effectively deliver quercetin to the porcine skin ex vivo. The amount of quercetin retained in the skin after application of MC-based preparations containing higher concentrations of quercetin was 2.04-fold higher for CMC-based hydrogels and 2.6-fold higher for SA-based hydrogels.

Open Access Agricultural Journals published by Institute of Agricultural Economics and Information

Together with vitamin C, zinc, selenium, manganese, and magnesium play a vital role in the preservation of organs scheduled for transplantation. In the present study, it is shown that addition of 1 mg/l of these elements influences the stability of 0.3 mM ascorbic acid solutions. The solution’s stability was estimated using an accelerated stability test. The concentration of vitamin C was measured using a validated spectrophotometric method, which uses the reduction of 2,6-dichlorophenoloindophenol by ascorbic acid. Elevated temperatures, the factor accelerating substances’ decomposition reaction rate, were used in the tests. The research was conducted at two temperatures at intervals of 10 °C: 80 ± 0.1 and 90 ± 0.1 °C. It was stated that the studied substances’ decomposition occurred in accordance with the equation for first-order reactions. The function of the logarithmic concentration (log%C) over time was revealed to be rectilinear. This dependence was used to determine the kinetics of decomposition reaction rate parameters. The stabilization of vitamin C solutions was measured as the time in which 10 % of the substance decomposed at 20 and 0 °C. Addition of Se(IV) or Mg(II) ions significantly increase the stability of ascorbic acid solution (∼34 and ∼16 %, respectively), but Zn(II) causes a significant decrease in stability by ∼23 %. Addition of Mn(II) has no significant influence on vitamin C stability.

The aim of the study was to evaluate the effect of iodine yeast (I-yeast) supplementation on the performance, egg traits, and iodine content of eggs of laying hens. The experiment was conducted as a completely randomized design. A total of 60 laying hens (Hy-Line Brown), 25 wk of age, was divided into 3 groups (4 replicates), and a feeding experiment was conducted for 12 wk. The concentrations and forms of iodine added to the basal diet were as follows: control group, 1 mg of iodine/kg of feed, Ca(IO3)(2)center dot H2O; experimental groups E1 and E2, 1 and 2 mg of iodine per kilogram of feed, I-yeast, respectively. The iodine yeast did not significantly affect BW gain. Lower level of hen day egg production for groups E1 and E2 was not confirmed statistically; however, it was probably the consequence of low replication. Feed intake was the lowest in the E1 group and feed conversion rate was the highest in the E2 group. Furthermore, the egg and albumen weight was the highest in the group supplemented with 2 mg/kg of iodine from I-yeast (P < 0.05). The concentration of iodine in the egg yolk from groups E1 and E2 was respectively about 80 and 90% higher, compared with the control group. Eggshells from the group fed with 2 mg/kg of I-yeast contained almost 3 times more iodine than eggshells from the control group. The results suggest that iodine yeast supplementation in the diet of laying hens is an effective method for increasing iodine concentration in eggs and thus could contribute to elimination of iodine deficiency disorders in humans consuming iodine-enriched eggs.

Insulin loaded to the polymer network of hydrogels may affect the speed and the quality of wound healing in diabetic patients. The aim of our research was to develop a formulation of insulin that could be applied to the skin. We chose hydrogels commonly used for pharmaceutical compounding, which can provide a form of therapy available to every patient. We prepared different gel formulations using Carbopol^® Ultrez^TM 10, Carbopol^® Ultrez^TM 30, methyl cellulose, and glycerin ointment. The hormone concentration was 1 mg/g of the hydrogel. We assessed the influence of model hydrogels on the pharmaceutical availability of insulin in vitro, and we examined the rheological and the texture parameters of the prepared formulations. Based on spectroscopic methods, we evaluated the influence of model hydrogels on secondary and tertiary structures of insulin. The analysis of rheograms showed that hydrogels are typical of shear-thinning non-Newtonian thixotropic fluids. Insulin release from the formulations occurs in a prolonged manner, providing a longer duration of action of the hormone. The stability of insulin in hydrogels was confirmed. The presence of model hydrogel carriers affects the secondary and the tertiary structures of insulin. The obtained results indicate that hydrogels are promising carriers in the treatment of diabetic foot ulcers. The most effective treatment can be achieved with a methyl cellulose-based insulin preparation.

The transdermal route of administration of drug substances allows clinicians to obtain a therapeutic effect bypassing the gastrointestinal tract, where the active substance could be inactivated. The hormonal substance used in the study-corticotropin (ACTH)-shows systemic effects. Therefore, the study of the effect of the type of ointment base and drug concentration on the release rate and also permeation rate in in vivo simulated conditions may be a valuable source of information for clinical trials to effectively optimize corticotropin treatment. This goal was achieved by preparation ointment formulation selecting the appropriate ointment base and determining the effect of ACTH concentration on the release and permeation studies of the ACTH. Semi-solid preparations containing ACTH were prepared using Unguator CITO e/s. The release study of ACTH was tested using a modified USP apparatus 2 with Enhancer cells. The permeation study was conducted with vertical Franz cells. Rheograms of hydrogels were made with the use of a universal rotational rheometer. The dependence of the amount of released and permeated hormone on the ointment concentration was found. Based on the test of ACTH release from semi-solid formulations and evaluation of rheological parameters, it was found that glycerol ointment is the most favourable base for ACTH. The ACTH release and permeation process depends on both viscosity and ACTH concentration. The higher the hormone concentration, the higher the amount of released ACTH but it reduces the amount of ACTH penetrating through porcine skin.