Facile synthesis of a new fluorogenic metal scavenging interpolymeric diamide based on cellulose and alginic acids.

A microwave assisted synthesis of a water soluble fluorogenic interpolymeric diamide has been described involving alginic acid and polyglucuronic acid (PGA) amide of ethylenediamine (EDA), through a monoamide of PGA and EDA, in good yields (>80wt% in each step). PGA was prepared by TEMPO (2,2,6,6-tetramethyl piperidine-1-oxyl radical) mediated oxidation of cellulose of the halophytic plant Salicornia brachiata. The amides were characterized by spectral analyses. The fluorescence emission of the PGA amide was 7-fold greater than that of the interpolymeric diamide. PGA monoamide exhibited superior heavy metal ions [Pb(II) and Hg(II)] uptake properties to the diamide, the former showing optimum adsorptions of ions 398.8 and 282.8mg/g, respectively. These materials may be of utility as potential sensors harnessing their fluorogenic and metal scavenging properties.