Enhancement of electrochemical detection of Pb 2+ by sensor based on track-etched membranes modified with interpolyelectrolyte complexes

This article concerns studies of flexible track-etched membrane modification by photograft polymerization of methacrylic acid and subsequent formation of interpolyelectrolyte complexes with poly(allylamine) for enhancement of properties of electrochemical sensor. Optimal conditions leading to functionalization of the surface and maintenance of the pore structure were found. Membranes were characterized by SEM, FTIR, XPS, gas permeability and colorimetric assay. Square wave anodic stripping voltammetry (SW-ASV) was used for detection of Pb2+. Limits of detection (LOD) for sensors based on non-modified PET TeMs, membranes modified by graft polymerization of methacrylic acid (PET TeMs-g-PMAA) and membranes modified with interpolyelectrolyte complexes with poly(allylamine) (PET TeMs-g-PMAA-PAlAm) are 3.03, 2.78 and 1.25 µg/L, respectively. Thus, it was shown that the formation of interpolyelectrolyte complexes on the membranes leads to a more accurate detection of lead ions.