International journal of pharmaceutics
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This paper describes design and evaluation of parenteral lecithin-based nanoemulsions intended for brain delivery of risperidone, a poorly water-soluble psychopharmacological drug. The nanoemulsions were prepared through cold/hot high pressure homogenization and characterized regarding droplet size, polydispersity, surface charge, morphology, drug-vehicle interactions, and physical stability. ⋯ Pharmacokinetic study demonstrated erratic brain profiles of risperidone following intraperitoneal administration in selected nanoemulsions, most probably due to their different droplet surface properties (different composition of the stabilizing layer). Namely, polysorbate 80-costabilized nanoemulsion showed increased (1.4-7.4-fold higher) risperidone brain availability compared to other nanoemulsions and drug solution, suggesting this nanoemulsion as a promising carrier worth exploring further for brain targeting.
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WHO estimates that 10% of drugs are falsified. Economic and health factors arising from the use of counterfeit drugs lead to the development of new methods for distinguishing genuine medicines from falsified ones. The purpose of this study was to develop a new, fast, and inexpensive method to distinguish between original and fake drugs. 10 counterfeit Viagra(®) tablets were compared to 4 original pills (Pfizer). ⋯ Differences in the dynamics of temperature changes as a function of time are particularly pronounced in the range of t+2 to t+7 min. The comparison of the time constants τ enables to distinguish between genuine and counterfeit drugs. The proposed new method which uses dynamic thermal analysis is an effective, cheap and fast technique to distinguish genuine drugs from counterfeit ones.
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The feasibility of a novel reverse-phase wet granulation process has been established previously and several potential advantages over the conventional process have been highlighted (Wade et al., 2014a,b,b). Due to fundamental differences in the growth mechanism and granule consolidation behaviour between the two processes the reverse-phase approach generally formed granules with a greater mass mean diameter and a lower intragranular porosity than those formed by the conventional granulation process under the same liquid saturation and impeller tip speed conditions. The lower intragranular porosity was hypothesised to result in an increase in the granule strength and subsequent decrease in tablet tensile strength. ⋯ No correlation was found between mean granule fracture strength and the tablet tensile strength (p>0.05) for either granulation approach. These data support the rejection of the original hypothesis which stated that an increase in granule strength may result in a decrease in the tablet tensile strength. The similar tablet tensile strength observed between the conventional and reverse-phase granulation processes indicated that while mechanistic differences exist in the formation of the granules, which resulted in significant granule-scale fracture strength differences, the granule compaction properties at pharmaceutically relevant tableting pressures were unaffected.
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The aim of our study was to investigate the influence of pH and temperature on the stability of ziconotide in analgesic admixtures containing morphine and ropivacaine. ⋯ Our admixtures showed different stability depending on the drug concentrations, pH and temperature. The great majority of mixtures in real life in our institution have stability highly compatible with our practice and with the delay between two pump refilling.
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Reutilization of single-use vials containing medical drugs is still under discussion. This practice has been adopted as a standard to avoid drug wastage, particularly in developing countries and in the aftermath of disasters. Some studies have assessed sterility of medications stored in single-use vials after utilization as multiple doses; however, most of these were limited to one single drug, included a low number of samples and did not consider an intermediate transfer step from the vial to a disposable syringe. The purpose of this study was to assess microbial contamination of samples withdrawn over three days from disposable syringes prepared from single-use vials. ⋯ This study demonstrated that contents initially stored in single-use vials and subsequently transferred into disposable syringes in an operating room using sterile technique, maintain sterility after 4 withdrawals per day for a total of 3 days.