Evaluation of physicochemical properties as supporting information on quality control of raw materials and veterinary pharmaceutical formulations.

This study aimed to show that the physicochemical proprieties obtained by Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and scanning electronic microscopy (SEM) can be useful tools for evaluating the quality of active pharmaceutical ingredients (APIs) and pharmaceutical products. In addition, a simple, sensitive, and efficient method employing HPLC-DAD was developed for simultaneous determination of lidocaine (LID), ciprofloxacin (CFX) and enrofloxacin (EFX) in raw materials and in veterinary pharmaceutical formulations. Compounds were separated using a Gemini C18 (250 mm × 4.6 mm, 5 µm) Phenomenex® column, at a temperature of 25 °C, with a mobile phase containing 10 mM of phosphoric acid (pH 3.29): acetonitrile (85.7:14.3, v/v) and a flow rate of 1.5 mL/min. Physicochemical characterization by TG, FTIR, and SEM of raw materials of LID, CFX, and EFX provided information useful for the evaluation, differentiation, and qualification of raw materials. Finally, the HPLC method was proved to be useful for evaluation of raw material and finished products, besides satisfying the need for an analytical method that allows simultaneous determination of EFX, CFX, and LID, which can also be extended to other matrices and applications.

Drug-excipient compatibility assessment of solid formulations containing meloxicam.

Meloxicam (MLX) is a non-steroidal anti-inflammatory cyclooxygenase (COX) inhibitor that is used to relieve inflammation and pain. MLX has a preferential affinity for COX-2, which is associated with a lower incidence of gastrointestinal side effects. The drug belongs to Class II of the Biopharmaceutical Classification System (BCS) in which dissolution is the limiting step of its bioavailability. In view of this classification, carrying out further studies regarding the compatibility of MLX with excipients and the mechanisms and kinetics of its degradation reactions is fundamental because any changes would directly influence the quality of the product. The aim of the present work is to evaluate solid pharmaceutical formulations containing MLX found on the market to define the more suitable excipients to improve the stability of the pharmaceutical formulations. Thermal analysis techniques were used to characterize and evaluate the compatibility between the drug and the excipients present in the market formulations. In the evaluation of its solid-state kinetics, MLX raw material under inert conditions had a shelf life of approximately 6years. In the study of compatibility between the drug and excipients, MLX was found to be incompatible with magnesium stearate after DSC analysis under binary mixtures, which was confirmed by stress studies and chromatographic analyzes.

Quality evaluation of pharmaceutical formulations containing hydrochlorothiazide.

Hydrochlorothiazide is a diuretic used to treat hypertension that belongs to class IV of the Biopharmaceutics Classification System. The drug was evaluated by quality control, thermal characterization tests, and pharmaceutical formulation compatibility studies. It was concluded that the generic drug, Lab 2, was not a pharmaceutical equivalent. The compounded drugs, Lab 5 and Lab 6, produced unsatisfactory but expected results, since there is no requirement for dissolution and dissolution profile testing for the commercialization of these products. In a compatibility study, lactose and mannitol were shown to be incompatible with HCTZ, which may explain the lack of equivalence of the generic pharmaceutical product, associated with other situations.

The validation of an analytical method for sulfentrazone residue determination in soil using liquid chromatography and a comparison of chromatographic sensitivity to millet as a bioindicator species.

Commonly used herbicides, such as sulfentrazone, pose the risk of soil contamination due to their persistence, bioaccumulation and toxicity. Phytoremediation by green manure species has been tested using biomarkers, but analytical data are now required to confirm the extraction of sulfentrazone from soil. Thus, the present work was carried out to analyze sulfentrazone residues in soil based on liquid chromatography with a comparison of these values to the sensitivity of the bioindicator Pennisetum glaucum. The soil samples were obtained after cultivation of Crotalaria juncea and Canavalia ensiformis at four seeding densities and with three doses of sulfentrazone. The seedlings were collected into pots, at two different depths, after 75 days of phytoremediator sowing and then were used to determine the herbicide persistence in the soil. A bioassay with P. glaucum was carried out in the same pot. High-performance liquid chromatography (HPLC), using UV-diode array detection (HPLC/UV-DAD), was used to determine the herbicide residues. The HPLC determination was optimized and validated according to the parameters of precision, accuracy, linearity, limit of detection and quantification, robustness and specificity. The bioindicator P. glaucum was more sensitive to sulfentrazone than residue determination by HPLC. Changes in sulfentrazone concentration caused by green manure phytoremediation were accurately identified by the bioindicator. However, a true correlation between the size of the species and the analyte content was not identified.