Potentiometric Determination of Prednisolone in Pharmaceutical Formulations

In this present work, a prednisolone ion selective electrode (PRED-ISE) has been developed. The electrode shows linear response towards prednisolone in the range 3.0×10−6 – 8.6×10−3 M with a detection limit of 2.5×10−6. PRED-ISE was used as an indicator electrode for the potentiometric titration of different concentrations of standard prednisolone against standardized sodium tetraphenyl borate solution and in tablets. The electrode manifests advantages of low resistance, fast response and, most importantly, good selective relativity to a variety of other cations.

Assessment of gross lesions preservation methods for the direct diagnosis of bovine tuberculosis: a constant search for improvement

Objectives The present study assessed the sensitivity and biosafety of the FTA Elute Card® (FTA) (GE Healthcare) as an alternative preservation method of gross lesions for bovine tuberculosis diagnosis, that can endure large distances and high environmental temperatures, which are found in the Brazilian territory. Results The FTA card was compared to the freezing and sodium borate solution methods to preserve 134 gross lesions samples from slaughterhouses located in three Brazilian states. The calculated value for the sensitivity of sodium borate solution (SBS) stored for 30 days was higher than those estimated for the methods of freezing and SBS stored for 60 days, when the PCR and isolation results were interpreted in parallel (0.55). The FTA cards presented the lowest diagnostic sensitivity and did not inactivate all mycobacteria. Given the rush of a slaughterhouse routine, the quantity of lesions with different pathological stages cannot be measured on each FTA card. Thus, as a preservation method of gross tuberculosis lesions, the FTA cards can present infection risks for people who have direct or indirect contact with them.

Voltammetric growth of tin oxides in borate solution of pH 8.7

<p class="PaperAbstract"><span lang="EN-US">Voltammetry has been employed to study the growth of tin oxides in buffer solution of 0.3 mol L^-1 H₃BO₃ + 0.15 mol L^-1 Na₂B₄O₇·10H₂O (pH 8.7). Voltammetric data were compared with the results of tin in a phosphate solution of pH 8.7, presented in the previous work, in order to study the influence of these anions on the growth of tin oxides. The thicknesses of grown oxides were determined using ex-situ ellipsometric technique and the volume per charge unity of the film, V_f, was calculated for different charge densities of the film. The results showed that less dense films were obtained at higher sweep rates. Tin oxide films grown in phosphate solution at 2 mV s^-1 were denser than those grown in borate solution at the same sweep rate. The kinetic parameters, determined applying the ohmic model, showed that there are no significant differences between the kinetics at the metal/film interface of tin in borate and tin in phosphate solutions. Despite these facts, the ionic specific resistivity for oxide film growth in borate solution were significantly higher than in phosphate solution. This result indicates that incorporation of anions occurs during the growth of the films.</span></p>

Anion-exchange synthesis of a nanoporous crystalline CoB2O4 nanowire array for high-performance water oxidation electrocatalysis in borate solution

A nanoporous crystalline CoB2O4 nanowire array (CoB2O4/TM) behaves as a superior water oxidation catalyst electrode, requiring an overpotential of 446 mV to deliver 10 mA cm−2 in 0.1 M K-Bi (pH = 9.2).