Determination of methylparaben in cosmetic products using a luminescent sensor Тb (ІІІ) - 2,2'-dipyridyl

Tb(III)-2,2'dipyridyl complex is offered to be used as a luminescent sensor for methylparaben determination. The luminescent properties of the complex of Tb(III) ion with 2,2'-dipyridil and methylparaben in a solid layer of sorbent were studied: absorption spectra, luminescence, excitation, the triplet levels of the ligands. It is established that the complex is efficient transfer of excitation energy from the ligand to the lanthanide ion, resulting in intense luminescence of the latter. The optimal conditions of complex formation were selected: the optimal concentration of solutions of terbium chloride (III), dipyridyl, methylparaben. The method of direct fluorescent determination of methylparaben in the means for removing makeup on the sensitized luminescence of ion Tb(III) was developed. The detection limit of methylparaben in means for removing makeup is 2,7 10-3 mg/sm3. This method advantageously differs from existing by absence of toxic reagents, expensive equipment, by short duration of analysis, allows to carry out rapid skrining of different cosmetic products.