Stability is an important parameter to evaluate the quality, safety and efficacy of drug substances and pharmaceutical products. The stability studies aim to determine the ability of a formulation to maintain its specifications, in order to establish shelf life and recommended storage conditions. Despite the extensive relevance, until the 1980’s the stability assessment methods complied with technical and scientific principles without the intervention of regulatory acts by health authorities. The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) establishment in the 1990’s boosted the regulation on this issue, not only in the attended countries, but worldwide. In the Brazilian context, the first regulatory norm for stability studies was published in 2002 and it implied the requirement of the submission of a stability report for the sanitary registration of medicines. The development of the Brazilian legislation resulted, among other factors, from the progress of the analytical methods that have become increasingly efficient, sensitive and selective, which allows the achievements of results with greater accuracy and speed; and the use of modern techniques of solid form characterization, which provide important information about the stability of active ingredients and pharmaceutical products.

Thermal analysis can be used to determine shelf-life and kinetic parameters in pharmaceutical systems. This work investigates the kinetic of lumefantrine thermal decomposition, an antimalarial, using non-isothermal and isothermal experimental data. The non-isothermal conditions are analyzed applying Vyazovkin method, while isothermal conditions employ models fitting procedure and artificial neural network. Lumefantrine was characterized by powder X-ray diffraction and Fourier transform infrared spectroscopy. The initial stage of lumefantrine thermal decomposition, about 5% of conversion, corresponds to the loss of chlorine and hydroxyl, being correctly predicted by the neural network as a complex event. At room temperature, the D3 model is appropriate to describe the process, once the half-life time is 19 months, in agreement with manufacturer. Isoconversional model determined the activation energy along the whole process while isothermal methodology determined the global value considering the entire process. The results provide important information for the pharmaceutical industry to assay levels of acceptable lumefantrine contents.

Gadodiamide (Gd-DTPA-BMA) is a gadolinium (Gd) chelate composed of two carboxylate groups of diethylenetriaminepentaacetic acid (DTPA) and two amide groups (BMA). Gd complexes are the most widely used contrast agents in nuclear magnetic resonance. Furthermore, our research group has demonstrated the potential of liposomes containing Gd-DTPA-BMA for cancer therapy. The aim of this study was to develop and validate a chemometric-assisted method by hydrophilic interaction liquid chromatography (HILIC) for determination of Gd-DTPA-BMA in liposomes. The chromatographic conditions obtained were: Sequant® ZIC®-HILIC Merck (150 × 4.6 mm, 3.5 µm, 100 Å) column, mobile phase composed of 5 mmol L-1 ACN/NH4FA, pH 4.5 (60:40 v/v) at 0.6 mL min-1, injection volume of 20 µL, temperature of 30 ºC, and detection at 210 nm. The linear range was of 40 to 120 nmol mL-1. The use of chemometrics allowed obtaining optimal chromatographic parameters, in terms of signal-to-noise ratio, resolution, and asymmetry.

ABSTRACT Prednisone is an anti-inflammatory steroid drug widely used in clinical practice. However, no high-performance liquid chromatographic (HPLC) method has been described in the literature for the determination of prednisone in capsules until now. Thus, an HPLC method was developed using a C18 (250x4.0, 5 µm) column, with methanol:water (70:30) as mobile phase at a flow rate of 1 mL/min and detection at 240 nm. The developed method was validated following current Brazilian legislation. Additionally, linearity was assessed by evaluating the assumptions of normality, homoscedasticity, and independency of residuals, and the fit to the linear model. The method showed linearity (r2>0.99) over the range of 14.0-26.0 µg/mL, selectivity, precision (RSD<2.0%), robustness, and accuracy (average recovery of 100.05%). The chromatographic procedure was applied for assay and uniformity content determination of three different batches of prednisone capsules, showing to be suitable for their quality control.

Polímeros Molecularmente Impressos (MIPs) são polímeros sintéticos que apresentam alta seletividade a uma molécula de interesse. O objetivo deste trabalho foi a síntese e caracterização de MIPs para aplicação na extração em fase sólida (SPE), visando a determinação de fenilalanina. Os MIPs foram sintetizados a partir do MAA, fenilalanina, EGDMA, AIBN, em clorofórmio. Também foi sintetizado o polímero não-impresso (NIP), para controle da seletividade dos MIPs. A dessorção da fenilalanina foi realizada em extrator Soxhlet. Os MIPs e NIP foram caracterizados pelas técnicas de análise: FTIR, UV-Vis, MEV, DSC e TG. O MIP apresentou maior capacidade adsortiva à fenilalanina do que o NIP, com uma taxa média de adsorção de 55% comparada a 11% para o NIP. Por MEV o MIP apresentou superfície mais porosa, importante característica para aplicação em SPE. Os estudos realizados mostraram que o MIP sintetizado apresentou grande potencial para aplicação em técnica de SPE.

Abstract Molecularly imprinted polymers (MIPs) are synthetic polymers that have high selectivity to a molecule of interest. The objective of this work was the synthesis and characterization of MIPs for use in solid phase extraction (SPE), in order to determine Phenylalanine. The MIPs were synthesized from the MAA, Phenylalanine, EGDMA AIBN, in chloroform. Non imprinted polymer (NIP) was synthesized to control the selectivity of MIPs. The desorption of Phenylalanine was carried out in Soxhlet extractor. The MIPs and NIP were characterized by the following analytical techniques: FTIR, UV-Vis, SEM, DSC and TG. MIP showed higher adsorption capacity to Phenylalanine than the NIP with an average rate of adsorption of 55% compared to 11% for NIP. SEM MIP showed more porous surface, an important feature for use in SPE. The synthesized MIP in the present study showed great potential for use in SPE technique.

Bisphosphonates are drugs that have been widely used in different bone diseases, and have recently been used successfully against many parasites. Various synthetic routes to prepare different types of bisphosphonates have been described, with distinct potency and pharmacological activity. A number of analytical techniques are currently being used to analyze these drugs; among these, the high performance liquid chromatography (HPLC), with different systems of detection, is worth highlighting. However, the development of more sensitive methods is still necessary, once they are essential for bioavailability and bioequivalence studies. This paper reports the major synthesis routes, chemical analysis methodologies and pharmacological applications of bisphosphonates.

A lamivudina é um fármaco indicado para o tratamento de infecção por HIV, tipos 1 e 2. Tem sido extensivamente utilizada no Brasil, em programa público do Ministério da Saúde. Visando à verificação da qualidade dos medicamentos contendo este fármaco foi estabelecida e validada metodologia para determinação do teor da lamivudina. Foi também realizado estudo de equivalência farmacêutica frente ao medicamento referência. Parâmetros físicos e físico-químicos de comprimidos de liberação imediata de diferentes lotes de quatro laboratórios (G, A, B e C) foram avaliados. O método proposto para o doseamento, por cromatografia líquida de alta eficiência, mostrou precisão, exatidão, linearidade e especificidade. Os lotes dos laboratórios G, A e B apresentaram resultados adequados em todos os testes aos quais foram submetidos. O produto G (referência) mostrou similaridade entre seus lotes com dissolução rápida. Os produtos A e B mostraram diferenças entre seus lotes, mas ao final do tempo determinado alcançaram cedência semelhante ao do produto G, sendo considerados equivalentes farmacêuticos ao medicamento referência. Os lotes do produto C não foram similares entre si e apresentaram baixa dissolução, não possuindo qualidade adequada para o consumo humano.

Lamivudine is a drug used in the treatment of types 1 and 2 HIV infections. It has been widely used in Brazil, in public programs of the Health Ministry. This work reports lamivudine assay methodologies, which have been developed and validated. Pharmaceutical equivalency studies were also performed for lamivudine tablets. Physical and physicochemical parameters of immediate release reference and test tablets of four different laboratories (G, A, B and C) were evaluated. The proposed analytical method, high performance liquid chromatography, presented satisfactory precision, accuracy, linearity and specificity. Batches from laboratories G, A and B showed appropriate results in all tests to which they were submitted. Tablet batches from laboratory G (reference) showed similar dissolution profile and fast dissolution rate. The products A and B showed differences between their batches, in regards to the dissolution rates at the initial profile. However at the end of the profile they reached similar release to the reference, product G. Therefore they can be considered pharmaceutical equivalents to the reference product. Batches of product from laboratory C showed much more differences with reduced dissolution presenting no appropriate quality for human consumption.