Pyrrole bearing diazocrowns: Selective chromoionophores for lead(II) optical sensing

Diazocrowns of 18-, 21-and 23-membered rings with pyrrole residue as a part of macrocycle were for the first time used as chromoionophores in lead(II) selective optodes. Sensing properties of optodes depend on the type of macrocycle, namely its size and the type of linker: oligoether or hydrocarbon chain. The best results were ob-tained for optode bearing 18-membered crown with oligoether linker showing linear response range of 8.05 x 10(-8)-2.24 x 10(-5) M lead(II) and detection limit of 1.15 x 10(-8) M. Membrane, based on cellulose triacetate, is lead(II) selective giving color change from red to different shades of blue (pH 5.5). Results obtained for model and real samples of lead(II) showed that easily accessible and regenerable sensor material can be used for spectrophotometric and colorimetric (Digital Color Analysis) detection and determination of lead(II).

Automated summary

In this study, diazocrowns of different sizes and different linker types were used as lead(II) selective optodes for the first time. The optode with an 18-membered crown and an oligoether linker showed the best results, making it suitable for lead(II) detection.