Multivariate Optimization of an SPME Technique for GC-MS Analysis of Urinary BTX.

Volatile organic compounds (VOCs), such as benzene, toluene and xylenes (BTX), are recognized as environmental contaminants due to their acute and chronic toxic effects, and toluene is a substance contained in products used in inhalants. In this way, methods able to determine these substances in non-invasive matrices offer great applicability for assessing acute exposure. In this study, a functionalized polymer, chloropropyltrimethoxysilane/polydimethylsiloxane, was evaluated as a potential material to be used in solid-phase microextraction for the quantification of BTX in urine by gas chromatography coupled to mass spectrometry (GC-MS).

Preclinical evaluation of methotrexate-loaded polyelectrolyte complexes and thermosensitive hydrogels as treatment for rheumatoid arthritis.

This work proposes new methotrexate (MTX) loaded drug delivery systems (DDS) to treat rheumatoid arthritis via the intra-articular route: a poloxamer based thermosensitive hydrogel (MTX-HG), oligochitosan and hypromellose phthalate-based polyelectrolyte complexes (MTX-PEC) and their association (MTX-PEC-HG). MTX-PEC showed 470 ± 166 nm particle size, 0.298 ± 0.