Suitability of ionic liquids as mobile-phase additives in HPLC with fluorescence and UV detection for the determination of heterocyclic aromatic amines.

The effects of several ionic liquids (ILs) as mobile-phase additives in HPLC with fluorescence and UV-Vis detection for the determination of six heterocyclic aromatic amines were evaluated using two different C(18) stationary phases with moderate silanol activity. The studied ILs were 1-butyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate and 1-methyl-3-octylimidazolium tetrafluoroborate. The optical behaviour of heterocyclic aromatic amines in presence of ILs was studied and the silanol-suppressing potency of ILs was evaluated for the two stationary phases studied.

Ionic liquids as mobile phase additives in high-performance liquid chromatography with electrochemical detection: application to the determination of heterocyclic aromatic amines in meat-based infant foods.

The beneficial effects of several ionic liquids (ILs) as mobile phase additives in high-performance liquid chromatography with electrochemical detection for the determination of six heterocyclic aromatic amines (HAs) have been evaluated for first-time. The studied ionic liquids were 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm-BF(4)), 1-hexyl-3-methylimidazolium tetrafluoroborate (HMIm-BF(4)) and 1-methyl-3-octylimidazolium tetrafluoroborate (MOIm-BF(4)). Several chromatographic parameters have been evaluated in the presence or absence of ILs, or using ammonium acetate as the most common mobile phase additive, with three different C18 stationary phases.

Ionic liquids as desorption solvents and memory effect suppressors in heterocyclic aromatic amines determination by SPME-HPLC fluorescence.

The beneficial effects of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIm-BF(4)) ionic liquid (IL) as mobile phase additive, desorption solvent, and memory effect suppressor in solid-phase microextraction (SPME)-high-performance liquid chromatography with fluorescence detection for the determination of six heterocyclic aromatic amines have been evaluated for the first time. Several chromatographic parameters have been evaluated in the presence or absence of IL or using triethylamine as the most common mobile phase additive, with a Nova-Pak C18 stationary phase. This IL was found to be clearly superior to triethylamine for efficiency as well as peak shape enhancement and sensitivity increase.

Determination of less polar heterocyclic amines in meat extracts: fast sample preparation method using solid-phase microextraction prior to high-performance liquid chromatography-fluorescence quantification.

A procedure for the determination of less polar heterocyclic amines in meat extracts using solid phase microextraction (SPME) coupled to high-performance liquid chromatography (HPLC) with fluorescence detection is presented. Analytes were first extracted from the samples using methanol/NaOH by an ultrasound-assisted method, and then concentrated on a Carbowax-templated resin (CW-TPR) SPME fiber. The extraction conditions such as extractant mixture composition, extraction time and extractions number, were optimized and the need of an extract freezing step previous to SPME is discussed.