Study of vortex-assisted MSPD and LC-MS/MS using alternative solid supports for pharmaceutical extraction from marketed fish.

A procedure based on vortex-assisted matrix solid-phase dispersion (MSPD) for the extraction of 15 pharmaceuticals from fish samples with determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was validated. Florisil, C18, diatomaceous earth, chitin, and chitosan were evaluated as solid supports. Best results were obtained with 0.5 g of diatomaceous earth, 0.5 g of sodium sulfate, and 5 mL of methanol. Analytical recoveries ranged from 58 to 128 % with relative standard deviation (RSD) lower than 15 %. Limit of quantification (LOQ) values for the 15 compounds ranged from 5 to 1000 ng g(-1). The method under investigation has shown to be a simple and fast extraction tool with minimum instrumentation and low amount of reagent, resulting in method low cost. Besides, alternative materials, such as chitin and chitosan, which were applied to the dispersion step for the first time, were found to be interesting alternatives.

Synthesis and antimycobacterial activity of isoniazid derivatives from renewable fatty acids.

This work describes the synthesis of a series of fatty acid hydrazide derivatives of isoniazid (INH). The compounds were tested against Mycobacterium tuberculosis H37Rv (ATCC 27294) as well as INH-resistant (ATCC 35822 and 1896 HF) and rifampicin-resistant (ATCC 35338) M. tuberculosis strains. The fatty acid derivatives of INH showed high antimycobacterial potency against the studied strains, which is desirable for a pharmaceutical compound, suggesting that the increased lipophilicity of isoniazid plays an important role in its antimycobacterial activity.

Sample as solid support in MSPD: A new possibility for determination of pharmaceuticals, personal care and degradation products in sewage sludge.

A method based on matrix-solid phase dispersion (MSPD), focused on the principles of green analytical chemistry, aimed at the use of alternative solid supports and less toxic solvents, was developed for the simultaneous determination of 19 pharmaceuticals, 4 personal care products (PPCPs) and 4 degradation products in sewage sludge samples. Higher recoveries were achieved when 2 g sample was macerated for 5 min in a glass mortar, transferred to a centrifuge tube, and 1 min vortex agitation with 5 mL methanol. The performance of the method was evaluated through linearity, recovery, precision (intra-day), method detection and quantification limits (MDL and MQL) and matrix effect. The calibration curves prepared in methanol and in the matrix extract showed a correlation coefficient ranging from 0.98 to 0.99. MQL values ranged from 1.25 to 1250 ng g-1. Recoveries between 50 and 120% were reached with RSDs lower than 20% for most compounds. The method presented low and medium matrix effects for most analytes. This method was successfully applied to real samples and of the 27 compounds determined, amitriptyline, carbamazepine, diclofenac, haloperidol, ketoconazole, miconazole, albendazole, mebendazole, thiabendazole, triclosan and triclocarban were detected in concentrations between 2.5 and 5400 ng g-1.