Flow injection green method for the quantitative analysis of ketoconazole in pharmaceutical preparations

A flow injection method for the quantitative analysis of ketoconazole in tablets, based on the reaction with iron (III) ions, is presented. Ketoconazole forms a red complex with iron ions in an acid medium, with maximum absorbance at 495 nm. The detection limit was estimated to be 1×10--4 mol L-1; the quantitation limit is about 3×10--4 mol L-1 and approximately 30 determinations can be performed in an hour. The results were compared with those obtained with a reference HPLC method. Statistical comparisons were done using the Student's t procedure and the F test. Complete agreement was found at the 0.95 significance level between the proposed flow injection and the HPLC procedures. The two methods present similar precision, i.e., for HPLC the mean relative standard deviation was ca. 1.2% and for FIA ca. 1.6%.

A formação humana na perspectiva histórico-ontológica

The theme of human formation is at the centre of the philosophy of education, whose aim is precisely the process of human promotion brought about by education. Starting from the critical vigilance proper to philosophy, the text sketches a phenomenology of the present time, verifying that the ideas prevailing in education at present are centred on the critique of reason and on the notions of truth and objectivity. This neo-pragmatism, which in the attempt to oppose metaphysics becomes deeply metaphysical, reducing everything to language, is contested by the authors with Marx's thoughts as a historicising philosophy that concerns not abstract subjects, but real individuals, historical subjects that are constituted as a synthesis of social relations. To that end, the authors resort to the historical ontological reflection on human formation contained in Marx's Economic and Philosophical Manuscripts of 1844. The article concludes by defending the proposition that access to the classics is a necessary condition for human formation.