Spectrophotometric determination of nevirapine using tetrathiocyanatocobalt(II) ion as a reagent

A simple and rapid spectrophotometric method for the determination of nevirapine is described. The method is based on the reaction of nevirapine with tetrathiocyanatocobalt(II) ion in buffer of pH 4 to form the corresponding complex. Beer's law is obeyed in the range of 0.2 - 2.0 µg mL-1 for nevirapine. The optical parameters such as molar absorptivity, Sandell's sensitivity, detection limit and quantitation limit were found to be 1.16× 10(4) Lmol-1cm-1, 2.09 X 10-3 µg cm-2, 0.073 µg mL-1 and 0.222 µg mL-1 respectively. The optimum reaction conditions and other analytical parameters were evaluated. The statistical evaluation of the method was examined by determining intra-day and inter-day precision. The proposed method has been successfully applied for the determination of nevirapine in pharmaceutical formulations.

Synthesis, characterization and thermal behaviour of heavy trivalent lanthanide malonates

Solid-state Ln-L compounds, where Ln stands for heavy trivalent lanthanides (Tb-Lu) and L is malonate, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, TG-FTIR system, elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The dehydration of the compounds begins at 303 K and the anhydrous compounds are stable up to 548 K. The results also provided information concerning the ligand's denticity, thermal behaviour and identification of some gaseous products evolved during the thermal decomposition of these compounds.

Effect of companion ion on nitrate displacement through transport parameters analysis

Nitrate is the main form of nitrogen associated with water contamination; the high mobility of this species in soil justifies the concern regarding nitrogen management in agricultural soils. Therefore, the objective of this research was to assess the effect of companion cation on nitrate displacement, by analyzing nitrate transport parameters through Breakthrough Curves (BTCs) and their settings made by numerical model (STANMOD). The experiment was carried out in the Soil and Water Quality Laboratory of the Department of Biosystems Engineering, "Luiz de Queiroz" College of Agriculture in Piracicaba (SP), Brazil. It was performed using saturated soil columns in steady-state flow condition, in which two different sources of inorganic nitrate Ca(NO3)2 and NH4NO3 were applied at a concentration of 50 mg L-1 NO3-. Each column was filled with either a Red-Yellow Oxisol (S1) or an Alfisol (S2). Results are indicative that the companion ion had no effect on nitrate displacement. However, nitrate transport was influenced by soil texture, particle aggregation, solution speed in soil and organic matter presence. Nitrate mobility was higher in the Alfisol (S2).

Complementary exams in blunt torso trauma. Perform only radiographs and fast: is it safe?

ABSTRACTObjective:to evaluate effectiveness of using chest X-ray (CXR), pelvis X-ray (RXP) and FAST (Focused Abdominal Sonography on Trauma) to exclude significant lesions of the body in blunt trauma.Methods:a prospective study involving 74 patients whom made the three tests (CXR, RXP and FAST) during the initial evaluation between October 2013 and February 2014. The results were compared to the tomography of the same patients or clinical outcome. If the patient did not have alterations on the CT scans or during the observation time, the initial workup was considered safe. All patients were evaluated at the Hospital João XXIII, Belo Horizonte, Brazil.Results:of the 74 patients studied the average age was 33 years, RTS: 6.98, ECG: 12. From 44 (59.45%) patients with exams (radiographs and FAST) unchanged, three had significant injuries (two splenic injuries and one liver injury) diagnosed by clinical monitoring. The remaining patients - 30 (40.55%) - had at least one alteration in conventional tests. Of these group 27 (90%) had significant injuries and three (10%) minor injuries. The sensitivity of all three tests for screening considerable lesions was 90% and the specificity was 93%. The negative predictive value was 93% and the positive predictive value 89%.Conclusion:this research showed that all the three exams - chest X-ray, pelvis and FAST - are safe to lead with the blunt trauma if well used and associated with clinical examination.