Edible oil-based switchable-hydrophilicity solvent liquid-liquid microextraction prior to smartphone digital image colorimetry for the determination of total curcuminoids in food samples.

Edible oil-based switchable-hydrophilicity solvent liquid-liquid microextraction was coupled with smartphone digital image colorimetry for the determination of total curcuminoids. Images of the colored extracts were captured in a laboratory-made colorimetric box, which were then split into their red-green-blue channels. Optimum extraction conditions were achieved using 550 μL of almond oil as the extraction solvent and 0.

Switchable-hydrophilicity solvent liquid-liquid microextraction combined with smartphone digital image colorimetry for the determination of palladium in catalytic converters.

Switchable-hydrophilicity solvent liquid-liquid microextraction was coupled with smartphone digital image colorimetry for the determination of palladium as its metal chelate with N,N-diethyl-N'-benzoylthiourea. Images of the colored extract were captured in a homemade colorimetric box, which were split into their red-green-blue channels. The blue channel was used to determine the concentration of palladium.