FIRST EDITION

Analysis of drugs requires standing search for reliable analytical techniques, essential to assure their identification and concentration in several matrices. In this context, the edition of scientific works has the objective of contributing with the researchers of the analytical area collaborating with the diffusion and knowledge related to this subject.The editorial team is celebrating the first volume of the journal Drug Analytical Research, a result of the effort of professors and collaborators who have taken up the challenge of expanding the analytical research involving therapeutic substances.The scope of the journal is focused on the analytical determination of drugs in different matrices, impurities, propositions of new analytical methods, as well as the systematic review of issues of separation and quantitative determination.At this moment, we would like to invite to access the website of the journal through the address (http://seer.ufrgs.br/index/php/dar) and appreciate the articles and reviews included in this first edition.Finally, we thank all those who supported this project, especially to Dra. Amanda Thomas Barden, who helped effectively in all stages of publication of this journal. Porto Alegre, August 28th, 2017Martin SteppeLead Editor                                                                                                                                                                                                                             

Development of a dissolution test for lamotrigine in tablet form using an ultraviolet method

A finalidade deste estudo foi desenvolver e validar um método de dissolução para o fármaco lamotrigina na forma farmacêutica comprimido. Este método também foi utilizado para comparar o perfil de dissolução entre o Neural® e o produto de referência Lamictal®. O procedimento analítico foi realizado utilizando-se espectrofotometria de absorção no ultravioleta (267 nm) como forma de quantificação do fármaco. Após a determinação da solubilidade e das condições sink, os parâmetros selecionados foram: pás (50 rpm), 900 mL de ácido clorídrico 0.01 M e o tempo de 30 minutos (único ponto). Este método foi validado através da especificidade, linearidade, exatidão, precisão e robustez. A estabilidade da lamotrigina também foi avaliada no meio de dissolução.A dissolution test for tablets containing 100 mg of lamotrigine was developed and validated. The dissolution test was applied to compare the dissolution profile of Neural® with the reference product Lamictal®. The analysis procedure was carried out using a simple ultraviolet method at 267 nm. After the determination of solubility and sink conditions, the parameters selected were paddles at 50 rpm, 900 mL of 0.01 M hydrochloric acid, and 30 minutes duration (single point). This method was validated for specificity, linearity, accuracy, precision and robustness. Lamotrigine stability was also evaluated in dissolution medium

Dissolution Test for Mianserin Hydrochloride in Tablets

A dissolution test for mianserin hydrochloride in coated tablets containing 30 mg was developed and validated using a fast ultraviolet spectrophotometric method. The appropriate conditions were determinate after testing sink conditions, agitation spped and dissolution medium. The sink conditions tested showed that mianserin hydrochloride was soluble in 0.01 and 0.1 M hydrochloric acid (HCl), acetate buffer pH 4.1 and 5.0 and phosphate buffer pH 6.8. Then, dissolution tests were performed to investigate the drug release in each medium. Optimal conditions to carry out the dissolution test were 900 mL 0.1 M HCl and USP apparatus 2 (paddle) at 50 rpm stirring speed. The quantification method was also adapted and validated. The UV method showed specificity, linearity, precision and accuracy. The in vitro dissolution test can be used to evaluate the drug release profile and the data was used as an aid to establish a possible correlation with in vivo data

Evaluation of Physical-Chemical and Microbiological Stability of Fluconazole Oral Suspensions for Hospital Use

Fluconazole is an important drug in the treatment of cutaneous and systemic mycoses. The Hospital de Clínicas de Porto Alegre performs a derivation of fluconazole capsules to obtain an oral liquid formulation that is easily administered and whose dose can be adjusted. In order to replace the derivation for a formulation produced from an active pharmaceutical ingredient, this study sought to develop a liquid oral formulation, evaluate its physical chemical and microbiological stability and demonstrate suitability of the analytical method for the formulation assay. Seven different formulations of pharmaceutical suspension form were produced and evaluated for pH, viscosity, sedimentation volume and assay. The analytical method by High Performance Liquid Chromatography was demonstrated. Two most promising formulations were manipulated in the Farmácia Semi-Industrial do Hospital de Clínicas de Porto Alegre and stored in amber PET bottles under three different conditions: room temperature, under refrigeration (2 to 8 ºC) and in an oven (40 ° C). Samples were collected after 0, 7 and 14 days to evaluate physical-chemical stability, assay, pH and macroscopic aspects. Samples were collected after 0 and 21 days to evaluate microbiological stability. It was possible to demonstrate stability for one of the formulations for a 14-day period. Throughout the study, the chosen formulation presented adequate quantification of fluconazole, constant pH, no organoleptic changes and no microbial growth. The results suggest the incorporation of a new formulation for fluconazole to the Farmacia Semi-Industrial portfolio)

Gemifloxacin mesylate: UV spectrophotometric method for quantitative determination using experimental design for robustness

This study describes the validation of UV spectrophotometric method for quantitative determination of gemifloxacin mesylate (GFM) in tablets using methanol as solvent. The method was specific, linear, precise, exact and robust at 272 and 343 nm. The results confirmed that the method in both wavelengths is valid and useful to the routine quality control of GFM in coated tablets. The validate method was compared to liquid chromatography (HPLC), microbiological assay and visible (VIS) spectrophotometry, which were previously developed and validated to the same drug. There was not significative difference between the methods for GFM quantitation

SECOND-ORDER DERIVATIVE UV SPECTROPHOTOMETRIC AND RP-HPLC METHODS FOR THE ANALYSIS OF VILDAGLIPTIN AND APPLICATION FOR DISSOLUTION STUDY

This study describes two analytical methods, by second-order derivative UV spectrophotometric by HPLC, for determination of vildagliptin, a drug used for treatment of type 2 Diabetes Mellitus that belongs to a therapeutic class called inhibitors of dipeptidyl peptidase 4. The methods were validated in accordance with ICH and USP requirements. Analyses by UV derivative method were performed at 220 nm, which was the zero crossing point of excipient solutions. HPLC was optimized and the analysis was carried out using a Zorbax Eclipse Plus RP-C8 column (150 mm × 4.6 mm, 5 μm), detection at 207 nm, and potassium phosphate buffer solution pH 7.0 : acetonitrile (85:15, v/v) as mobile phase. In dissolution test, the conditions used were 0.01 mol L-1 hydrochloric acid in 900 mL of dissolution medium, USP apparatus 2 (paddle) and 50 rpm stirring speed. Both methods were successfully applied for analysis of dissolution samples from marketed vildagliptin tablets