Seyed Abdollatif Hashemifard

The goal of this work is to develop an innovative technique for extracting ultra-trace level of metal ions from water samples based on membrane-based solid-phase microextraction (SPME) utilizing a dual layer hollow fiber (DLHF) consisting of self-polymerized tyrosine layer as an outer layer on polyacrylonitrile/Graphene Oxide (PAN/GO) as an inner layer (PAN/GO-Tyr DLHF) that has been further stabilized with ethanol. The incorporated tyrosine layer onto the surface of the PAN/GO could improve selectivity of extraction and provide additional mass transfer pathway. The PAN/GO-Tyr DLHF adsorbent structure were characterized by FTIR, XRD, AFM, FESEM and DLS analysis. Under optimized experimental conditions, the adsorbent demonstrated good linearity and correlation coefficients over the concentration ranges of Pb^(2+) (r2=0.989), Cu^(2+)(r2=0.974), Sn^(2+)(r2=0.999) and As^(3+) (r2=0.989) ppb and detection limit 4.5, 5, 20 and 20 ppb for As3+, Cu2+, Sn2+ and Pb2+, respectively. This technique identified ultra-trace level of ions at levels below the World Health Organization's permissible limits. The findings demonstrate the selectivity and sensitivity of the suggested approach, with high enrichment factors. Adsorption kinetics of analytes onto PAN/GO-Tyr DLHF adsorbent material was considered. The absorption kinetics fitted better with pseudo-second order (r2=0.998) and approved multiple layers adsorption mechanism and chemisorption process.