Novedosos sensores fluorescentes basados en el 2,4,6-tricloro-1,3,5-triazina para la detección de iones metálicos en solución

Abstract

The unique property of 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride) is its ability to undergo a nucleophilic aromatic substitution (SNAr) reaction under controlled temperature conditions. Using a convenient synthetic protocol, monosubstituted s-triazines were treated with an excess of nucleophiles to obtain optical sensors for di- and trisubstituted triazines in 1+1+1 mode (one nucleophile for the first substitution, followed by another nucleophile for the second, and another more for the last position). The nucleophiles used for this study were 5-amino-2,3-dihydrophthalazine-1,4-dione (luminol), n-butylamine, and 4-amino-1,5-dimethyl-2-phenylpyrazol-3-one. (4-Aminoantipyrine). The best order of incorporation for obtaining the optical sensors derived from cyanuric chloride and studying its coordinating capacity of metal ions in aqueous solution of this work was 4-aminoantipyrine for the first position followed by n-butylamine for the second position and the third position of the triazine nucleus with luminol. The sensor resulting from the synthesis of cyanuric chloride first with luminol as the first substituent and 4-aminoantipyrine as the second substituent has sensitivity when tested with solutions of heavy metals (Hg, Cd, Pb, Cr and Fe) of which all lower the fluorescence provided by luminol to the chemosensor. The detection limit for each heavy metal was given in concentration ranges in ppm (parts per million) and was 40-30 ppm for Hg+2, 70-60 ppm for Pb+2 and Cd+2, and 20-10 ppm for Cr+2.