cu(ii) modified magnetic chitosan nanocomposite for spe-trace detection of alizarin yellow gg

Abstract: the rapidly growing world population and rapid industrialization has caused the dyes to be widely used in some main domains such as textile related industries. many of the dyes are generally harmful and toxic to living creatures and mammals. one of the groups of the dyes are the azo based salicylic dyes. alizarin yellow gg (aygg) is one of the dyes with carcinogenic effects which causes serious problems to aquatic vegetal life and the environment. the effects are raised mainly due to its structural stability affording weak thermal and biological degradation [1]. magnetic solid phase extraction (mspe) has been developed based on the use of magnetic nanoparticles (mnps). mnps usually introduce a high surface area to volume ratio preparing the great extraction capacity and efficiency. furthermore, mnps are suitably dispersed and have superparamagnetic properties for easy magnetic collection and re-dispersion in the solutions [2]. a cross-linked magnetic chitosan nanocomposite was prepared and its structure and morphology were characterized by different spectroscopic and microscopic techniques, respectively. the preliminary experiments showed that the adsorbent was efficient for the adsorption of aygg when cu(ii) was present in the suspension. different parameters related to the adsorption and elution steps were considered during the optimization. the studies showed that a solution containing ammonia and sodium hydroxide was efficient on the both elution of aygg (from the adsorbent) and colorimetric-detection of aygg at 452 nm. the method introduced the linearity of absorbence against the aygg concentration in the ranges of 2-50 (r2 = 0.9979), 50-200 (r2 = 0.9933) and 200-2000 (r2 = 0.9965) nmol l-1 for aygg. also, a limit of detection equal to 0.7 nmol l-1 was found for aygg. further experiments showed that the accuracy, reproducibility, repeatability and selectivity of the method were excellent. different soil and water samples were successfully analyzed according to the appropriate standard addition methods.