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In this work, poly(MBAAm-co-SBMA) zwitterionic polymer nanoparticles were synthesized in one-step via distillation-precipitation polymerization (DPP) and were characterized. [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) as monomer and N, N′-methylene bis(acrylamide) (MBAAm) as cross-linker are used for the synthesis of nanoparticles. As  far as our knowledge, this is the first such report on the synthesis of poly(MBAAm-co-SBMA) nanoparticles via DPP. The newly synthesized nanoparticles were further employed for the surface modification of polysulfone (PSF) hollow fiber membranes for dye removal. The modified hollow fiber membrane exhibited the improved permeability (56 L/ m2 h bar) and dye removal (>98% of Reactive Black 5 and >80.7% of Reactive orange 16) with the high permeation of salts. Therefore, the as-prepared membrane can have potential application in textile and industrial wastewater treatment.

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In this paper, novel zwitterionic graphene oxide (GO) nanohybrid was synthesized using monomers [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) and N,N′methylenebis(acrylamide) (MBAAm) (GO@poly(SBMA-co-MBAAm), and incorporated into polysulfone (PSF) hollow fiber membrane for the effectual rejection of dye from the wastewater. The synthesized nanohybrid was characterized using ft-iR, pXRD, tGA, eDX, teM and zeta potential analysis. the occurrence of nanohybrid on the membrane matrix and the elemental composition were analyzed by XPS. The as-prepared tight ultrafiltration hollow fiber membrane exhibited high rejection of reactive black 5 (RB-5, 99%) and reactive orange 16 (RO-16, 74%) at a dye concentration of 10 ppm and pure water flux (PWF) of 49.6 L/m 2 h. Fabricated nanocomposite membranes were also studied for their efficacy in the removal of both monovalent (NaCl) and divalent salts (Na 2 So 4 ). the results revealed that the membrane possesses complete permeation to NaCl with less rejection of Na 2 So 4 (<5%). In addition, the nanocomposite membrane revealed outstanding antifouling performance with the flux recovery ratio (FRR) of 73% towards bovine serum albumin (BSA). Therefore, the in-house prepared novel nanocomposite membrane is a good candidate for the effective decolorization of wastewater containing dye.In recent times, wastewater generated from the textile industries becoming detrimental environmentally demanding effluent. It is mainly composed of a large amount of organic dyes and inorganic salts, properly ~5.6 wt% of Na 2 SO 4 and ~6 wt% of NaCl 1,2 . Among the organic dyes used, reactive dyes have gained significant attention owing to the low tendency of fixing on the fibers. Accordingly, a considerable amount of inorganic salts should be used to enhance the binding capability, which led to the existence of a large number of dyes and salts in the wastewater stream 3 . The discharge of untreated wastewater effluents into the environment, not only affect human beings but also restrict the permeation of light which will affect the aquatic flora and fauna to a greater extent 4-8 . Further, the discharged dye molecules are highly vulnerable to hydrolysis or oxidation to degrade into different toxic substances. Reactive dyes are capable of causing skin diseases like contact dermatitis and respiratory diseases like asthma 9 . In the matter of sustainability, dyes and inorganic salts should be separated from the wastewater and recycled rather than dye removal or water purification by reverse osmosis (RO). Additionally, the recycled dye can be used in the dyeing process and salts can work well as draw solution in forward osmosis (FO) 10-12 .Membrane separation is one of the efficient and popular techniques for the purification of wastewater 13-17 . In the 1980s, the nanofiltration (NF) membrane was introduced and has become an attractive technology due to the improved selectivity, high permeation, low operating pressure and less maintenance cost [18][19][20][21] . NF membrane has

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A thin-film nanocomposite (TFN) membrane was developed by integrating zwitterionic polymeric nanoparticles into the active layer of the membranes. High surface area zwitterionic polymeric nanoparticles (370 m 2 /g) were developed through distillation−precipitation polymerization (DPP). Sodium 4-vinylbenzenesulfonate (SVBS) was used as the monomer and N,N′methylenebis(acrylamide) (MBAAm) utilized as the cross-linking agent. L-cysteine (L-Cys) was tethered to these matrices through thiol−ene reaction. The assynthesized zwitterionic P(MBAAm-co-SVBS)@L-Cys nanoparticles were dispersed into the organic solution of trimesoyl chloride (TMC) to be integrated into the polyamide (PA) selective layer of thin film nanofiltration membranes. The PA layer was synthesized by interfacial polymerization through the reaction of 2% (w/ v) of piperazine (PIP) in the aqueous phase and 0.15% (w/v) of the TMC solution. The fabricated TFN membranes exhibited pure water permeability (J w ) of 11.4 L/m 2 h bar and salt rejection value of 97.6% and 16.9%, for sodium sulfate and sodium chloride, respectively. The fabricated membranes demonstrated metal ion removal efficiencies of 99.48% and 95.67% for Pb 2+ and Cd 2+ ions, respectively.

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Design and construction of automated synthesizers using the tilted plate centrifugation technology is described. Wash solutions and reagents common to all synthesized species are delivered automatically through a 96-channel distributor connected to a gear pump through two four-port selector valves. Building blocks and other specific reagents are delivered automatically through banks of solenoid valves, positioned over the individual wells of the microtiterplate. These instruments have the following capabilities: Parallel solid-phase oligonucleotide synthesis in the wells of polypropylene microtiter plates, which are slightly tilted down towards the center of rotation, thus generating a pocket in each well, in which the solid support is collected during centrifugation, while the liquid is expelled from the wells. Eight microtiterplates are processed simultaneously, providing thus a synthesizer with a capacity of 768 parallel syntheses. The instruments are capable of unattended continuous operation, providing thus a capacity of over two millions 20-mer oligonucleotides in a year.