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Cromatografia líquida bidimensional aplicada a senosídeos e na determinação simultânea de diclofenaco sódico, paracetamol e cafeína
(Universidade Federal de São Carlos, 2012-10-25) Favarin, Fábio Henrique Pinheiro; Carneiro, Renato Lajarim; https://lattes.cnpq.br/8065852319463976; https://lattes.cnpq.br/5043755089274025
In this study are proposed analytical methods involving the two-dimensional liquid chromatography for drug analysis. The twodimensional liquid chromatography (LC × LC) provides an increase in peak separation ability as compared with the technique dimensional. With its more powerful separation occurs reducing co-elutions, allowing better quantification. The orthogonal separation based on different separation mechanisms may improve the selectivity and facilitate analysis of compounds in complex samples. One of the principles characterizing 2D-LC technique is to use orthogonal methods to each other, thus peaks are eluted in the sequence A, B, C in the first column are eluted into another sequence in the second column that is orthogonal to the first . Selectivity is the ability of the chromatographic system of discriminating different analytes and is determined as the ratio of the retention factor of two analytes, or the ratio of the retention times. In the method 2D-LC, fractions should be collected after passing through a first column and reinjected into another column, thus, a chromatographic run 10 minutes at a flow rate of 1 ml / min, collecting fractions of 1 mL, 10 represents new injections. These fractions reinjected into a second column chromatograms new generation 10, which when joined together give rise to a chromatographic surface. Two-dimensional chromatograms are important to evaluate overlapping chromatographic peaks not able to be viewed on a conventional chromatographic analysis. The samples used for both tests were quantified by calculation of content and it was found that methods are needed, reproductive and fractions collected when compared with quantified method had good initial recovery. Methods have been developed for determination of senosides (series of anthraquinone derivatives with laxative effect), and dimeric occurring glycosides abundant in plants of the genus Senna and methods for determining the content of diclofenac sodium, paracetamol and caffeine. The samples were subjected to stress conditions to evaluate the appearance of new substances, characterized as impurities and / or degradation products. Comparing the results between one-dimensional and two-dimensional technique, note the significant increase in the selectivity of the peaks, and the resolution between them. In a dimensional analysis often requires a very long running time for complete separation of the peaks. Developing two-dimensional methods can significantly reduce the running time on a first column, causing the overlapping peaks are separated in a second stationary phase, gaining in selectivity.
Avaliação da cicatrização da pele de rato wistar após múltiplas sessões de terapia fotodinâmica
(Universidade Federal de São Carlos, 2012-10-25) Angarita, Dora Patricia Ramirez; Kurachi, Cristina; https://lattes.cnpq.br/0194007981724312; https://lattes.cnpq.br/7317761382511787
Nonmelanoma skin cancer is the most frequent disease in the world population and it is becoming a public health problem. Due to this fact, new technologies are being tested for the treatment of this disease. Photodynamic Therapy (PDT) is a noninvasive technique with an excellent cosmetic outcome, well tolerated by patients and with good healing results when used for the initial stages of cancer lesions. PDT uses molecular oxygen, light at appropriate wavelengths and the drug photosensitizers to generation of reactive oxygen species such as singlet oxygen responsible for the photoinactivation of target cells. The characteristics of scar tissue after multiple sessions of PDT is not completely understood. It is not known whether multiple sessions of PDT may cause irreversible changes in the treated tissue. Thus, the present study has as its main objective the evaluation of the characteristics of the skin scarred after multiple sessions of PDT. For this study, we used 25 Wistar type male mice. These 25 mice were grouped into 5 subgroups of 5 each: G0, control group, non-subjected to any treatment; G1, exposed to one PDT session and after, there was made a lesion with CO2 laser over the scarred tissue; G2, the group is submitted twice for the same procedure, G3, subjected to 3 times the procedure performed for G1 group; G4, exposed to 4 times the procedure. Once the mice s skin was healed, we performed macroscopic and microscopic evaluations of the histological pieces. Furthermore, we made a microscopic evaluation of collagen fibers and the generation of the second-harmonic through multiphotons microscopy. Macroscopically, it was observed a good healing for the different groups. The aesthetic result showed a decrease after the third and fourth sessions. In the microscopic study, it was observed an conservation of the quantity of sebaceous glands per square millimeter (mm2). The morphology of collagen fibers when evaluated using two-photon excited fluorescence in the confocal microscope, showed thinner fibers with a parallel arrangement and lower density in the G3 e G4 compared to the control group. It was not observed decrease in the generation of second harmonic in histopathology slides. These results suggest that healing in skin after four (4) sessions of PDT/lesion presents alterations in aesthetic and histological of the morphology of collagen fibers that may be related to submitted of the skin in eight (8) consecutive occasions with an incomplete healing between them.