Fortunato Anna, Mba Miriam
Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy.
Gels. 2022 Oct 19;8(10):672. doi: 10.3390/gels8100672.
The removal of dyes and pharmaceuticals from water has become a major issue in recent years due to the shortage of freshwater resources. The adsorption of these pollutants through nontoxic, easy-to-make, and environmentally friendly adsorbents has become a popular topic. In this work, a tetrapeptide-pyrene conjugate was rationally designed to form hydrogels under controlled acidic conditions. The hydrogels were thoroughly characterized, and their performance in the adsorption of various dyes and pharmaceuticals from water was investigated. The supramolecular hydrogel efficiently adsorbed methylene blue (MB) and diclofenac (DCF) from water. The effect of concentration in the adsorption efficiency was studied, and results indicated that while the adsorption of MB is governed by the availability of adsorption sites, in the case of DCF, concentration is the driving force of the process. In the case of MB, the nature of the dye-hydrogel interactions and the mechanism of the adsorption process were investigated through UV-Vis absorption spectroscopy. The studies proved how this dye is first adsorbed as a monomer, probably through electrostatic interactions; successively, at increasing concentrations as the electrostatic adsorption sites are depleted, dimerization on the hydrogel surface occurs.
近年来，由于淡水资源短缺，从水中去除染料和药物已成为一个主要问题。通过无毒、易于制备且环保的吸附剂吸附这些污染物已成为一个热门话题。在这项工作中，合理设计了一种四肽-芘共轭物，使其在可控的酸性条件下形成水凝胶。对水凝胶进行了全面表征，并研究了它们从水中吸附各种染料和药物的性能。这种超分子水凝胶能有效地从水中吸附亚甲基蓝（MB）和双氯芬酸（DCF）。研究了浓度对吸附效率的影响，结果表明，虽然MB的吸附受吸附位点可用性的控制，但对于DCF而言，浓度是该过程的驱动力。对于MB，通过紫外-可见吸收光谱研究了染料与水凝胶相互作用的性质以及吸附过程的机制。研究证明，这种染料首先以单体形式吸附，可能是通过静电相互作用；随后，随着浓度增加，由于静电吸附位点耗尽，水凝胶表面会发生二聚化。
