Biofunctionalized nanofibrous membranes mimicking carnivorous plants

Abstract

A novel biofunctionalized nanofibrous membrane is developed through immobilization of protein ligands on the surface of nanofibers. The biofunctionalization not only enhances the membrane's structural properties including mechanical and thermal ones but also makes the membrane capable to separate nanoparticles and biomolecules much smaller than the pore size from water efficiently. Upon contact with water, the conformational change of the protein immobilized leads to its swelling, thereby an enlarged functional surface area and a higher steric hindrance capturing the filtrates. In case of filtration of a plasmonic nanoparticle containing suspension, decoration of the membrane with the plasmonic nanoparticles forms a smart bionanocomposite biosensor for detection of protein denaturation. IntroductionMembrane technology for water treatment is steadily gaining very high importance worldwide. This is primarily due to water pollution and dwindling fresh water supplies leading to water scarcity. Water quality has to be controlled to ensure a safer environment by implementing efficient technologies such as advanced membranes offering more output with less input, that is, efficient energy saving membranes. Electrospun nanofibrous membranes (ENMs) that have the potential to be used as advanced membrane systems will be able to remove pollutants from the environment at lower energy and hence cost.1 Energy saving by ENMs derives from their high interconnected porosity leading to a very high permeability.2 Despite an extraordinary permeability, ENMs suffer from low size selectivity. Microfiltration (MF) range pore size of ENMs makes them efficient in removing relatively coarse particles and suspended solids but not tiny substances smaller than the pore size. [3][4][5][6][7] Considering the importance of separation of nanoparticles also organics that can be detrimental to the quality of water systems, optimizing the selectivity of such membranes could be crucial. Accordingly, not only the high permeability of the membrane is preserved but also on the basis of selectivity, the application domain would be extended from MF to ultrafiltration (UF) and even nanofiltration. Long-term functionality, that is, longevity of ENMs with regard to their extraordinary surface area thereby a higher exposed surface to the water streams is dependent on their mechanical stability. Hence, to maximize the efficiency of an ENM, besides the optimization of the selectivity, its mechanical stabilization should be also stressed.Here, we show that through one-single approach, that is, protein functionalization, an ENM can acquire mechanical and thermal stability while showing more optimum selectivity. Inspired by the

An Overview of the Water Remediation Potential of Nanomaterials and Their Ecotoxicological Impacts

“…Moreover, extensive available surface area and flexibility in surface functionality optimize the adsorptive nature and selectivity of the nanofibrous membranes. The constituting nanofibers could be as neat, chemically functionalized, nanocomposite, and even biofunctionalized [46][47][48][49][50]. For instance, a PES electrospun nanofiber mat overlaid on a poly(ethylene terephthalate) (PET) non-woven was evaluated as a membrane for liquid filtration and removal of micro-and submicron sized polystyrene (PS) particles from water [51].…”

An Amphiphilic, Graphitic Buckypaper Capturing Enzyme Biomolecules from Water

“…Their purification action mainly relies on sieving of the pollutants, and thus they require a porous structure whose pore size is less than the size of the solute to be separated. Other than the membranes, in a sustainable manner and using conventional and also emerging materials, functionalized adsorbents have shown applicability in the removal of even molecules and tiny pollutants based on physical/chemical interactions or biological functions [2][3][4][5][6][7]. Accordingly, there is no need for the construction of porous materials with small pore sizes that could impose high pressure differences.…”

“…[8][9][10][11]. In our studies [2,4,12], we also developed a biofunctionalized nanofibrous adsorbent composed of Bovine Serum Albumin and poly(acrylonitrile-co-glycidyl methacrylate) (PANGMA), as the functional agent and polymer nanofiber, respectively, that could offer a significant metal nanoparticle and biomolecule removal efficiency while being highly water permeable. This adsorbent was synthesized in a simple fashion versus the other previously developed systems [8,13].…”

A Buckypaper Like Adsorbent Based on Amphiphilic Graphite Nanofilaments for Removal of Enzyme Biomolecules from Water

“…Their separation action is mainly based on sieving of the pollutants, thus they require a porous structure whose pore size is smaller than the solute size. Other than the membranes, functionalized adsorbents have shown applicability in removal of even molecules and tiny pollutants based on physical/chemical interactions or biological functions [2][3][4][5][6]. Accordingly, there is no need to construction of porous materials with very small pore sizes that could impose high feed pressures.…”

“…[7][8][9][10]. In our studies [2,4,11], we also developed a biofunctionalized nanofibrous adsorbent composed of Bovine Serum Albumin and poly(acrylonitrile-co-glycidyl methacrylate) (PANGMA), as the functional agent and polymer nanofiber, respectively, that could offer a significant metal nanoparticle and biomolecule removal efficiency while being highly water permeable. This adsorbent was synthesized in a simple manner versus its already established counter parts [7,12].…”