Layered double hydroxide nanoparticles for a smartphone digital image colorimetry-based determination of fluoride ions in water, milk and dental products.

A novel smartphone digital image colorimetry-based approach was developed for fluoride ion determination, using layered double hydroxide (LDH) nanoparticles (MgAl(OH)) as sorbents for analyte preconcentration and as a source of a central metal ion for a colored complex formation. A cotton rotating disk provided effective retention of the LDH nanoparticles during solid-phase microextraction and elution, excluding time-consuming centrifugation process. In the proposed procedure, the nanoparticles acted as aluminum ion source for alizarin complexone-Al-F complex formation.

Alkyl polyglucoside-based supramolecular solvent formation in liquid-phase microextraction.

The phenomenon of alkyl polyglucoside-based supramolecular solvent formation in the presence of alkyl carboxylic acid acted as coacervation agent was described for the first time. Various alkyl polyglucosides and carboxylic acids were studied as the amphiphiles and coacervation agents, respectively. A possible mechanism of the new supramolecular solvent formation was presented.