M. Bodnar, A-L Kjoniksen, J.F. Hartmann, L. Daróczi, B. Nystrom and J. Borbely
Recently, reduction of water consumption by industry has been an important challenge. Enhanced ultrafiltration with polymers is a feasible method to remove metal ions from diluted wastewater streams. Biomacromolecules, biodegradable polymers as biomaterials have an important role in a wide range of industrial fields such as water treatment.3,4 For separation of toxic heavy metal ions, including lead ions, several natural polymers have been investigated. The most valuable properties of these biopolymers are their biocompatibility, biodegradability, and flocculating activity for metal ions. The present investigation describes the preparation and characterization of novel biodegradable nanoparticles based on complexation of poly-gamma-glutamic acid (PGA) with bivalent lead ion. The prepared nano-systems were stable in aqueous media . In neutral and alkali media, the carboxylic groups of PGA are deprotonated, and the repulsive electrostatic forces between the negatively charged parts affect the physicochemical properties of these particles. In acidic media, γ-PGA is an uncharged macromolecule, and this may lead to smaller sizes of the γ-PGA/Pb2+ particles unless the concentrations of the components in the mixture are sufficiently high to form intermolecular complexes.