Facile liquid colorimetric sensor using high-density deep eutectic solvent for trace detection and speciation of iron in milk.

An efficient colorimetric sensor was developed using a high-density deep eutectic solvent (HD-DES) for the trace detection and speciation of iron in various milk samples. A liquid colorimetric probe was fabricated by dissolving ferrozine (FZ) in HD-DES prepared from TBABr and PBA. The prederivatization of Fe via complexation with FZ on the HD-DES/FZ probe provided the [Fe(FZ)] complex, which led to a color change from pale yellow to purple before it was simultaneously extracted by HD-DES.

A novel liquid colorimetric probe for highly selective and sensitive detection of lead (II).

A novel liquid colorimetric sensor based on deep eutectic solvent (DES) was developed for the preconcentration and detection of Pb in fruit juice, milk and cereal samples. The colorimetric probe was simply fabricated by adding dithizone (DZ) into DES, prepared from choline chloride and phenol. Pb was formed complex with DZ in the probe, providing hydrophobic complex of [Pb-DZ] which was simultaneously extracted into DES and the color was changed from light orange to carmine red.

A Simple in Syringe Low Density Solvent-Dispersive Liquid Liquid Microextraction for Enrichment of Some Metal Ions Prior to Their Determination by High Performance Liquid Chromatography in Food Samples.

A simple and highly sensitive method is developed for the simultaneous determination of Ni, CrO, Co, and Hg by using in syringe low density solvent-dispersive liquid liquid microextraction (ISLD-DLLME), followed by high performance liquid chromatography with a UV detector. The four metal ions were derivatized with pyrrolidine dithiocarbamate (PDC) based on complexation before their enrichment by ISLD-DLLME in which 1-octanol and methanol were used as the extraction solvent and the dispersive solvent, respectively. The extraction was performed in a commercially available syringe under vortex agitation.