To develop an analytical method to simultaneous quantification of benznidazole (BNZ) and posaconazole (POS) by high-performance liquid chromatography with diode-array detection (HPLC-DAD) using design of experiments. Percentages of organic phase, buffer pH and flow rates of mobile phase were selected as independent variables by full factorial design (33), totaling 27 experiments. Significant factors were evaluated using factorial analysis of variance with 95% confidence level. Method optimization was performed using desirability profiles, considering BNZ/POS chromatographic resolution and peak areas. Further, the method was evaluated regarding its suitability and properly validated according to the international compendiums using the parameters: specificity, linearity, accuracy, precision, limit of detection and limit of quantification. The optimized method was achieved using Discovery® C8 column (250 mm × 4.6 mm; 5 μm particle size), methanol/acetate buffer (pH 3.5)(71:29) and detection at 260 nm. Retention times were 3.6 and 7.6 min for BNZ and POS, respectively, with good suitability of system and it was specific and linear (r2 >0.99) for both drugs, proving the efficiency of the method even in the presence of degradation products of POS. This new method is a great alternative to perform reliable, faster and cheaper analysis since the simultaneous quantification of the association BZN/POS is not reported yet in the literature.
1 January 2021 in Anais da Academia Brasileira de Ciências
The present study consisted in optimizing the extractive method of polyphenols and total tannins of leaves of Syzygium cumini (L) Skeels assisted by microwaves to potentiate the antimicrobial activity of the dried extract of S. cumini against sensitive and resistant strains. A Box-Behnken design that consisted of 27 experimental runs coupled with a desirability function for multiple response optimization was employed to optimize the total polyphenols content and total tannins content. Antimicrobial sensitivity tests were evaluated by obtaining the minimum inhibitory concentration, minimum fungicidal concentration and minimum bactericidal concentration in 96-well petri dishes. The optimal extraction conditions were found to be 8 min of extraction, under 300 w of microwave power, using a 1:34 g/mL solid/solvent ratio and 38% of ethanol concentration as extraction solvent. The parameter with the greatest influence in the extraction was primarily the time, followed by the potency and proportion solid/solvent. This yielded a total polyphenol content of 87.37 ± 1.85 mg TAE g-1ext and a total tannin content of 79.68 ± 1.64 mg TAE g-1 ext. All tested microorganisms were sensitive to the extract, evidencing the effectiveness of the extraction method optimization.
1 August 2019 in European Journal of Pharmaceutical Sciences
To perform the solid-state characterization and the in vitro-in vivo correlation (IVIVC) of three batches of efavirenz (EFV) active pharmaceutical ingredients.EFV is an effective anti-HIV drug. Due...