Reduced graphene oxide-coated magnetic-nanoparticles as sorbent for the determination of phthalates in environmental samples by micro-dispersive solid-phase extraction followed by ultra-high-performance liquid chromatography tandem mass spectrometry.

In this work, the suitability of FeO nanoparticles coated with reduced-graphene oxide as sorbent was evaluated for the extraction of a group of fourteen phthalic acid esters (i.e. benzylbutyl phthalate (BBP), bis-2-n-butoxyethyl phthalate (DBEP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), dicyclohexyl phthalate (DCHP), bis-2-ethoxyethyl phthalate (DEEP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), bis-isopentyl phthalate (DIPP), bis-(2-methoxyethyl) phthalate (DMEP), dimethyl phthalate (DMP), di-n-octyl phthalate (DNOP), bis-n-pentyl phthalate (DNPP), dipropyl phthalate (DPP)) from environmental samples.

Determination of phthalates in beverages using multiwalled carbon nanotubes dispersive solid-phase extraction before HPLC-MS.

A microdispersive solid-phase extraction method has been developed using multiwalled carbon nanotubes of 110-170 nm diameter and 5-9 μm length for the extraction of a group of nine phthalic acid esters (i.e., bis(2-methoxyethyl) phthalate, bis-2-ethoxyethyl phthalate, dipropyl phthalate, butylbenzyl phthalate, bis-2-n-butoxyethyl phthalate, bis-isopentyl phthalate, bis-n-pentyl phthalate, dicyclohexyl phthalate, and di-n-octyl phthalate) from tap water as well as from different beverages commercialized in plastic bottles (mineral water, lemon- and apple-flavored mineral water, and an isotonic drink).

Evaluation of two molecularly imprinted polymers for the solid-phase extraction of natural, synthetic and mycoestrogens from environmental water samples before liquid chromatography with mass spectrometry.

In this work, we have compared the selectivity of two commercial molecularly imprinted polymers (AFFINIMIP®SPE Estrogens and AFFINIMIP®SPE Zearalenone) for the extraction of 12 estrogenic compounds of interest (i.e. 17α-estradiol, 17β-estradiol, estrone, hexestrol, 17α-ethynylestradiol, diethylstibestrol, dienestrol, zearalenone, α-zearalanol, β-zearalanol, α-zearalenol and β-zearalenol) from different water samples.

Synthesis and pharmacological activity of diterpenylnaphthoquinone derivatives.

New diterpenylquinones, combining a diterpene diacid and a naphthoquinone, were prepared from junicedric acid and lapachol. The new derivatives were assessed as gastroprotective agents by the HCl-EtOH-induced gastric lesions model in mice as well as for basal cytotoxicity on the following human cell lines: Normal lung fibroblasts (MRC-5), gastric epithelial adenocarcinoma (AGS), and hepatocellular carcinoma (Hep G2). Several of the new compounds were significantly active as antiulcer agents and showed selective cytotoxicity against AGS cells.