The determination of chemical purity, melting range, and variation of enthalpy in the process of characterizing medicines is one of the principal requirements evaluated in quality control of the pharmaceutical industry. In this study, the method of purity determination using DSC was outlined, as well as the application of this technique for the evaluation of commercial samples of zidovudine (AZT) (raw material) supplied by different laboratories. To this end, samples from six different laboratories (A, B, C, D, E, and F) and the standard reference (R) from the United States Pharmacopeia (USP) were analyzed. The DSC curves were obtained in the temperature range of 25 to 200 o C under the dynamic atmosphere of N 2 (50 mL min , using an Al capsule containing approximately 2 mg of sample material. The results demonstrated that the standard reference presented a proportion of 99.83% whereas the AZT samples presented a variation ranging from 97.59 to 99.54%. In addition, the standard reference was found to present a temperature of onset of melting point of 122.80 °C. Regarding the samples of active agents provided by the different laboratories, a variation ranging from 118.70 to 122.87 °C was measured. In terms of DH m , the samples presented an average value of 31.12 kJ mol -1.Uniterms: Zidovudine/purity determination. Differential scanning calorimetry. Thermal analysis. Medicines/quality control. Medicines/qualitative analysis.A determinação da pureza química, a faixa de fusão e a variação de entalpia envolvida no processo de caracterização de fármacos é um dos principais requisitos avaliados no controle de qualidade em indústrias farmacêuticas. Neste trabalho é feita uma breve abordagem sobre o método de determinação de pureza utilizando DSC, assim como a aplicação desta técnica para avaliação de amostras comerciais de zidovudina (AZT) (matéria-prima) fornecida por diferentes laboratórios. Para tal, foram analisadas amostras de seis diferentes laboratórios (A,B,C,D,E e F) e a substância química de referência (R) da United States Pharmacopeia (USP). As curvas DSC foram obtidas na faixa de temperatura entre 25 a 200 o C, sob atmosfera dinâmica de N 2 (50 mL min -1 ), b=2 o C min -1 , utilizando cápsula de Al contendo aproximadamente 2 mg de amostra. De acordo com os resultados, pode-se observar que a substância química de referência apresentou teor igual a 99,83% e que as amostras de AZT apresentaram uma faixa de variação entre 97,59 e 99,54%. Pode-se verificar, ainda, que a substância química de referência apresentou uma temperatura onset de fusão igual a 122,80 °C. Para as amostras dos princípios ativos fornecidos pelos diferentes laboratórios, pode-se verificar uma faixa de variação entre 118,70 e 122,87 °C. No que se refere ao DH m , as amostras apresentaram valor médio de 31,12 kJ.mol -1 .Unitermos: Zidovudina/determinação da pureza. Calorimetria exploratória diferencial. Análise térmica. Medicamentos/controle de qualidade. Medicamentos/análise qualitativa.
O presente artigo visa apresentar e discutir possibilidades de sistemas de ações profissionais a partir da teoria da subjetividade em uma perspectiva cultural-histórica, de modo a avançar sobre temas e práticas historicamente ausentes na psicologia soviética. Para tanto, são discutidas ações profissionais em diferentes contextos, a saber, na psicoterapia, nas práticas escolares, na atuação em instituições de saúde e na comunidade. Essa proposta teórica implica uma concepção dialógica e não instrumental dos sistemas de ações profissionais e atribui uma forte importância à capacidade dos indivíduos e grupos de se posicionarem de forma ativa em seus diversos caminhos de vida, emergindo como sujeitos de suas próprias experiências. Nesse sentido, as práticas profissionais devem ser orientadas a favorecer o desenvolvimento humano, para além da resolução pontual de problemas específicos.
BackgroundThe present study was carried out to evaluate antioxidant, antinociceptive and anti-inflammatory activities of essential oil from R. maritima (RMO) in experimental protocols.MethodsThe essential oil from the roots and rhizomes of RMO were obtained by hydrodistillation using a Clevenger apparatus, and analyzed by gas chromatography/mass spectrometry (GC/MS). Here, we evaluated free radical scavenging activities and antioxidant potential of RMO using in vitro assays for scavenging activity against hydroxyl radicals, hydrogen peroxide, superoxide radicals, and nitric oxide. The total reactive antioxidant potential (TRAP) and total antioxidant reactivity (TAR) indexes and in vitro lipoperoxidation were also evaluated. The ability of RMO to prevent lipid peroxidation was measured by quantifying thiobarbituric acid-reactive substances (TBARS). NO radical generated at physiological pH was found to be inhibited by RMO, that showed scavenging effect upon SNP-induced NO production at all concentrations. Antinociceptive and anti-inflammatory properties were evaluated by acetic acid writhing reflex, Formalin-induced nociception and Carrageenan-induced edema test.ResultsThe majors compounds identified was remirol (43.2%), cyperene (13.8%), iso-evodionol (5.8%), cyperotundone (5.7%), caryophyllene oxide (4.9%), and rotundene (4.6%). At the TRAP assay, RMO concentration of 1 mg.mL−1 showed anti-oxidant effects and at concentration of 1 and 10 ng.mL−1 RMO showed pro-oxidant effect. RMO at 1 mg.mL−1 also showed significant anti-oxidant capacity in TAR measurement. Concentrations of RMO from 1 ng.mL−1 to 100 μg.mL−1 enhanced the AAPH-induced lipoperoxidation. RMO reduced deoxyribose oxidative damage, induced by the Fenton reaction induction system, at concentrations from 1 ng.mL−1 to 100 μg.mL−1. We observed that RMO caused a significant increase in rate of adrenaline auto-oxidation. On the other hand RMO did not present any scavenging effect in H2O2 formation in vitro. The results of this study revealed that RMO has both peripheral and central analgesic properties. The RMO, all doses, orally (p.o.) administered significantly inhibited (p < 0.05, p < 0.01 and p < 0.001) the acetic acid-induced writhings and two phases of formalin-induced nociception in mice.ConclusionThe RMO demonstrated antioxidant and analgesic profile which may be related to the composition of the oil.Electronic supplementary materialThe online version of this article (doi:10.1186/1472-6882-14-514) contains supplementary material, which is available to authorized users.
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