In-Situ Ag-MOFs Growth on Pre-Grafted Zwitterions Imparts Outstanding Antifouling Properties to Forward Osmosis Membranes
      Mehdi Pejman,  Mostafa Dadashi Firouzjaei, Sadegh Aghapour Aktij, Parnab Das, Ehsan Zolghadr, Hesam Jafarian, Ahmad Arabi Shamsabadi, Mark Elliott*, Marco Sangermano, Mohtada Sadrzadeh, Ahmad Rahimpour*, Alberto Tiraferri*
In this study, a polyamide forward osmosis membrane was functionalized with zwitterions followed by the in-situ growth of metal-organic frameworks with silver as metal core (Ag-MOFs) to improve its antibacterial and antifouling activity. First, 3-bromopropionic acid was grafted onto the membrane surface after its activation with N, N-diethylethylenediamine. Then, the in-situ growth of Ag-MOFs was achieved by a simple membrane immersion sequentially in a silver nitrate solution and in a ligand solution (2-methylimidazole), exploiting the underlying zwitterions as binding sites for the metal. The successful membrane functionalization and the enhanced surface wettability were verified through an array of characterization techniques. When evaluated in forward osmosis tests, the modified membranes exhibited high performance and improved permeability compared to pristine membranes. Static antibacterial experiments, appraised with confocal microscopy and colony-forming unit plate count, resulted in a 77% increase in the bacterial inhibition rate due to the activity of the Ag-MOFs. Microscopy micrographs of the E. coli bacteria suggested the deterioration of the biological cells. The antifouling properties of the functionalized membranes translated into a significantly lower flux decline in forward osmosis filtrations. These modified surfaces displayed negligible depletion of silver ion over 30 days, confirming the strong immobilization of Ag-MOFs on their surface.
                             Type                         Experimental
                             Publication           ACS Applied Material Interfaces
                             Date                          July 2020
                             Links                        URL
bacteria, E.coli, membranes, water_treatment, metal-organic frameworks, chemical
mostafadadashifirouzjaei, water, mark_elliott, environmental treatment, alberto_tiraferri, ahmad_rahimpour

author = {Pejman, Mehdi and Dadashi Firouzjaei, Mostafa and Aghapour Aktij, Sadegh and Das, Parnab and Zolghadr, Ehsan and Jafarian, Hesam and Arabi Shamsabadi, Ahmad and Elliott, Mark A. and Sadrzadeh, Mohtada and Sangermano, Marco and Rahimpour, Ahmad and Tiraferri, Alberto},
title = {In-Situ Ag-MOFs Growth on Pre-Grafted Zwitterions Imparts Outstanding Antifouling Properties to Forward Osmosis Membranes},
journal = {ACS Applied Materials \& Interfaces},
volume = {0},
number = {ja},
pages = {null},
year = {0},
doi = {10.1021/acsami.0c12141},
    note ={PMID: 32677425},

URL = {
eprint = {