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Unlabelled: The current trend of replacing conventional pharmaceutical forms is justified because most substances administered in this form give fluctuations of therapeutic concentrations and often outside the therapeutic range. In addition, these formulations offer a reduction in the dose or the number of administrations, thus increasing patient compliance., Aim: In the experiment, we developed an appropriate technology for the preparation of gelatin microspheres containing tramadol hydrochloride by emulsification/cross-linking method., Materials and Methods: The formulated microspheres were characterized by product yield, size distribution, encapsulation efficiency and in vitro release of tramadol hydrochloride. Data obtained from in vitro release studies were fitted to various mathematical models to elucidate the transport mechanisms. The kinetic models used were zero-order, first-order, Higuchi Korsmeyer-Peppas and Hopfenberg., Results: Spherical microspheres were obtained, with free-flowing properties. The entrapment efficiency of tramadol hydrochloride in microparticles was 79.91% and product yield -94.92%. As the microsphere size was increased, the entrapment efficiency increased. This was 67.56, 70.03, 79.91% for formulations MT80-250, MT8-500 and, MT250-500. High entrapment efficiency was observed for MT250-500 formulation. The gelatin microspheres had particle sizes ranging from 80 to 500 microm. The drug was released for a period of 12 hours with a maximum release of 96.02%. Of the three proposed formulations, MT250-500 presented desirable properties and optimal characteristics for the therapy of pain. Release of tramadol hydrochloridi was best fitted to Korsmeyer-Peppas equation because the Akaike Information Criterion had the lowest values for this kinetic model., Conclusions: These results suggest the opportunity to influence the therapeutic characteristics of gelatin microspheres to obtain a suitable drug delivery system for the oral administration of tramadol hydrochloride.

Unlabelled: The aim of flavonols complexation is to improve their specific activity., Material and Method: The flavonols sources were Morus alba L. and Morus nigra L., zinc being the biological active ion. Physico-chemical characterization was made by thin-layer chromatography, UV-VIS spectrophotometry, IR spectrometry and polarography., Results: The complexes results were within acceptability limits, but their obtaining is economically inefficient.

Indigene Stachys species have a high content in interesting compounds as iridoids, but also high quantities of flavonoids and phenol-carboxylic acids. These compounds present vasorelaxing effect on smooth vascular muscle interfering with metabolic degradation of nitric oxide pathways (inhibition of peroxynitrites formation) and by inhibition of phosphodiesterase. This work shows flavonoids spectrum of 3 Stachys species using HPLC methods. We identified quercetol, rutoside, miricetin and phenol-carboxylic acids (chlorogenic, caffeic and ferulic acids).