Download or read book Static and Dynamic Adsorption of beta lactoglobulin on Polymeric Membrane Surface and Development of Novel Membranes by Surface Modification written by JUN TAE. KIM and published by . This book was released on 2007 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The protein adsorption on polymeric membrane surface is the major factor to cause the membrane fouling in ultrafiltration (UF) processing to concentrate, fractionate, and separate whey proteins from liquid whey which is byproduct of cheese manufacturing process. Membrane fouling, which is defined as the decrease of the filtration performances such as permeation flux, efficiency, and selectivity is still one of the major problems encountered in many food industries employing membrane separation processing. In order to better understand fouling mechanism, to optimize the process condition to minimize fouling, and to develop the novel membranes to reduce fouling, the protein adsorption on the polymeric membrane surface was studied by static adsorption and dynamic adsorption experiments. From the static adsorption experiment, the adsorption capacity and the surface heterogeneity of [beta]-lactoglobulin were determined at various conditions of the protein solution by an adsorption isotherm. Dynamic adsorption process was studied by QCM-D, which allows monitoring of the protein adsorption process in real time by simultaneously measuring of frequency shift (delta f) and dissipation shift (delta D). To develop the novel membranes to reduce the protein adsorption and fouling, two surface modification methods were developed by hydrophilic polymers grafting using UV/Ozone treatment and thin film composite (TFC) through interfacial polymerization. The hydrophilic polymer grafted membranes might reduce the hydrophobic interactions between protein and membrane surface by improve the hydrophilicity of the polymeric membrane. UV/Ozone is one of the powerful techniques to initiate and activate the polymeric membrane surface to graft the hydrophilic polymers. Interfacial polymerization has been a well established way to prepare the thin active layer by a polycondensation reaction in two immiscible phases (organic solvent and water phase). Dense and thin polyamide layer can be formed on the polymeric membrane surface. The hydrophilic polymers such as PVA, PEG, and chitosan were modified on the polyamide thin layer to improve the hydrophilicity of the modified membranes. Some surface properties of modified PES membranes were characterized by contact angle, FT-IR, XPS, and AFM. These results proved that PES membranes were modified successfully with hydrophilic polymers and showed more hydrophilic property and lower protein adsorption.
Download or read book Polymer Membranes In Biotechnology Preparation Functionalization And Application written by Seeram Ramakrishna and published by World Scientific Publishing Company. This book was released on 2011-02-21 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a concise and comprehensive introduction of polymer membranes' preparation, functionalization and applications in biotechniques including affinity membrane chromatography, membrane-based biosensor and membrane-based bioreactor.Following an introduction to the general concept of membrane separation in Chapter 1, preparation of polymeric membranes is discussed in Chapter 2. The book then describes in Chapter 3 membrane surface activation, which is a key step in ligand immobilizations. Chapter 4 focuses on ligand immobilization techniques and the organic chemistries behind them. Chapter 5 introduces the application of affinity membrane chromatography. Finally, in Chapter 6, membranes used in biosensors and gas sensors, enzymatic membranes used as biosensor, and membrane biosensor for waste water treatment will be discussed.A novel filter medium, i.e. nonwoven nanofiber membrane, and its preparation method, i.e. electrospinning technique, are also introduced in this book./a
Download or read book Imprinted Polymeric Membranes written by Laura Donato and published by Walter de Gruyter GmbH & Co KG. This book was released on 2023-07-04 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Higly efficient separation tools are increasingly required for satisfying the necessity of the modern society. In this context, for achieving optimized separation and purification of targeted compounds, the typical features of the imprinting technology and membrane science for developing the so-called imprinted membranes have been exploited. Imprinted membranes are smart systems endowing selective recognition properties towards specific molecules and ions that exhibit better performance with respect to the traditional separation techniques. The aim of this monography is to give a contribution in promoting the knowlegde on the current research trend about this topic. Starting from the concept of the molecular recognition the book introduces the reader to the fascinating world of the imprinting technology and membrane-based processes up to discussing the development of imprinted polymers as well as imprinted membranes, which represent their special format. The different imprinting strategies as well as the theory and mechanisms of the separation are also explained. Furthermore, the application of molecularly imprinted polymeric membranes in different areas for the selective recognition of drugs, active pharmaceutical ingredients, pesticides, other toxic compounds and proteins is discussed. The attention is also devoted to their employment in enantiomeric separation, sensors technology and controlled drug delivery. Finally, the production and application of ion imprinted membranes in the separation of metal ions, rare earth element and anions and the role of cyclodextrins in the imprinting technology are discussed.
Download or read book Surface Modification of Polymer Membranes by Self organization written by Jonathan Forrest Hester and published by . This book was released on 2001 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biofunctional Membranes written by D.A. Butterfield and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: ''Interesting with many useful ideas and references. It covers a broad range and it is a good introduction to this field.'' ---Analyst
Download or read book Surface Modification of Polymeric Membranes and Silicon Filters written by Yuchun Wang and published by . This book was released on 1998 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymeric Membrane Bacterial Attachment Strategies written by Sweta Binod Kumar and published by . This book was released on 2023-09-28 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Polymeric membranes are extensively used in various applications such as water treatment, wastewater treatment, desalination, and other filtration processes. However, their performance is often compromised due to the attachment of bacteria on their surfaces, leading to biofouling and membrane fouling. Therefore, developing strategies to control bacterial attachment on polymeric membranes is crucial for maintaining their efficiency and longevity. In this book, Several Strategies have been explore to minimize bacterial attachment, including surface modifications to make the membranes more antifouling, self-cleaning, and resistant to biofilm formation. These modifications can be achieved through the incorporation of hydrophilic, hydrophobic, or zwitterionic materials, as well as using nanotechnology-based methods. Biocides and disinfectants have also been used to prevent bacterial attachment, although their usage is limited due to environmental concerns. Cleaning the membranes is also an important aspect of maintaining their performance. Membrane cleaning methods such as filtration, ultrafiltration, nanofiltration, and reverse osmosis can help remove bacteria and other contaminants from the membrane surface. However, frequent cleaning can also damage the membrane and reduce its lifespan, highlighting the need for fouling-resistant membranes. Membrane bioreactors have emerged as a promising alternative to traditional wastewater treatment methods. In this process, biofilm formation on the membrane surface is encouraged to promote biodegradation of organic matter. Bio-inspired materials that mimic the surface charge, surface energy, and surface topography of biological organisms have also been developed to minimize bacterial adhesion. The attachment of bacteria on the membrane surface is influenced by various factors, including surface charge, surface energy, surface topography, microbial communities, and extracellular polymeric substances (EPS). Quorum sensing and other signaling mechanisms also play a critical role in the formation of biofilms. Therefore, understanding the microbial ecology and physiology is crucial for developing effective strategies to control bacterial attachment. Overall, the control of bacterial attachment on polymeric membranes is a complex issue that requires a multidisciplinary approach. Strategies to prevent biofouling and membrane fouling should be developed while considering environmental impact, biodegradation, and the antimicrobial resistance of bacteria. The use of microbial adhesion and microbial physiology research can aid in the development of new strategies for effective bacterial attachment control.
Download or read book Adhesion and Adsorption of Polymers written by Lieng-Huang Lee and published by Springer. This book was released on 1980-03-01 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Honolulu is a most beautiful place, suitable for all occa sions. Its choice as the meeting site for the first Joint Chemical Congress between the American Chemical SOCiety and the Chemical Society of Japan was praised by scientists from both sides. During this Congress, the International Conference on Adhesion and Adsorption of Polymers was held at the Hyatt Regency Hotel between April 2 and 5, 1979. We had speakers from ten nations presenting over forty papers related to the subject matter. It was a memorable event. Unlike our two previous adhesion symposia held in 1971 and 1975, this was the first time in the same conference that we discussed both adhesion and adsorption of polymers simultaneously. These two important phenomena are not only inter-related, but also equally important in adhesive technology as well as biochemical processes. The papers presented to this Conference deal with these two phenomena from both fundamental and practical viewpoints. Furthermore, with the advance of new surface analytical techniques, the actual, microscopic happenings at the interfaces can be pin pointed. Thus, characterization of interface became one of the major focuses of this Conference. As a result, a broad coverage of the subject matter includes statistical thermodynamics, surface physics, surface analysis, fracture mechaniCS, viscoelasticity, failure analysis, surface modification, adsorption kinetics, bio polymer adsorption, etc. Thanks to the diligence of our contri butors, we are now able to publish the final papers in these two volumes.
Download or read book Adhesion and Adsorption of Polymers written by Lieng-Huang Lee and published by Springer. This book was released on 2013-04-15 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Honolulu is a most beautiful place, suitable for all occa sions. Its choice as the meeting site for the first Joint Chemical Congress between the American Chemical SOCiety and the Chemical Society of Japan was praised by scientists from both sides. During this Congress, the International Conference on Adhesion and Adsorption of Polymers was held at the Hyatt Regency Hotel between April 2 and 5, 1979. We had speakers from ten nations presenting over forty papers related to the subject matter. It was a memorable event. Unlike our two previous adhesion symposia held in 1971 and 1975, this was the first time in the same conference that we discussed both adhesion and adsorption of polymers simultaneously. These two important phenomena are not only inter-related, but also equally important in adhesive technology as well as biochemical processes. The papers presented to this Conference deal with these two phenomena from both fundamental and practical viewpoints. Furthermore, with the advance of new surface analytical techniques, the actual, microscopic happenings at the interfaces can be pin pointed. Thus, characterization of interface became one of the major focuses of this Conference. As a result, a broad coverage of the subject matter includes statistical thermodynamics, surface physics, surface analysis, fracture mechaniCS, viscoelasticity, failure analysis, surface modification, adsorption kinetics, bio polymer adsorption, etc. Thanks to the diligence of our contri butors, we are now able to publish the final papers in these two volumes.
Download or read book Membrane Processing written by Adnan Y. Tamime and published by John Wiley & Sons. This book was released on 2012-12-12 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last two decades, there have been significant developments in membrane filtration processes for the dairy and beverage industries. The filtration systems can be classified into four main groups: reverse osmosis, nanofiltration, ultrafiltration and microfiltration. The primary objective of this book is to assess critically the pool of scientific knowledge available to the dairy and beverages industry, as a tool for process and product innovation, quality improvement and safety. The book is divided into three main parts. Part I reviews the principals, developments and designs of membrane processes that are mainly used in commercial dairy and beverage applications. Part II provides information on the applications of membrane processes in the manufacture of dairy products, from on-farm concentration of milk as a pre-treatment for cheesemaking to fractionation of milk and whey to provide ingredients for food and other applications. Part III considers membrane applications during the manufacture of fruit juices, beer and cider, wine and vinegar. These include concentration, deacidification and dealcoholisation processes. Membrane Processing: Dairy and Beverages Applications is an ideal new reference for dairy and beverage processors involved in the application of membranes, both to aid the creation of novel products, and to improve their process economics. Students and lecturers of food and dairy science and technology will value its in-depth discussion of membrane processes, whilst readers based in the dairy industry will prize it as the most up-to-date and advanced volume yet published on this crucially important topic.
Download or read book Two Surface Modification Methods to Reduce Protein Fouling in Microfiltration Membranes written by and published by . This book was released on 2006 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protein fouling is a critical factor governing membrane performance in various filtration processes. In this study, we report two new surface modification techniques to modify 0.22greek small letter mu mixed cellulose esters membranes (MCE) and 0.20greek small letter mu, positively charged durapore membranes to reduce protein fouling. The first step in the modification of MCE membranes involves coating of the membrane with a monolayer of allyldimethylchlorosilane (ADCS). The silanized membrane is then covalently linked to Pluronic F127, a triblock copolymer of polyethylene oxide and polypropylene oxide (PEO-PPO-PEO) by UV irradiation at wavelengths>215 nm. The presence of PEO groups on the membrane surface increased the wettability of the membrane. Contact angle measurements confirmed that the degree of Pluronic grafting on the silanized membrane was a function of the UV exposure time. The hydraulic permeability and flux decline of the modified membrane during bovine serum albumin (BSA) filtration were nearly identical to the unmodified membrane. The modified membranes exhibited better cleaning characteristics compared to unmodified membranes upon back flushing with saline solution. The positively charged durapore membranes have been dip coated with random copolymers poly (oligoethylene glycol methacrylate co methacrylic acid), (OEGMA/MA), under four different conditions. The electrostatic adsorption of OEGMA/MA onto the membrane surface has been verified by streaming potential measurements. The ability of the modified membranes to resist protein adsorption has been verified by FTIR spectra. The hydraulic permeability and the flux decline data of the modified membranes were similar to the unmodified membranes and the cleaning characteristic of modified membranes showed improved performance.
Download or read book Fouling in Polymeric Membranes Modified with Low Temperature Plasma written by Jan Johansson and published by . This book was released on 1997 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study examines the fouling of polymeric membranes with albumin using four membranes with different hydrophilic/hydrophobic characteristics and pore structures. A radioactive tracer technique was used to study adsorption of albumin on these membranes. In the aqueous phase protein concentration range of 0-40 mg/ml, the adsorption isotherms were linear for polyvinylidene fluoride, nylon and polycarbonate membranes. Only for polypropylene membranes, was a nonlinear adsorption isotherm observed. For an aqueous phase concentration of 1 mg/ml, the most adsorption occurred on polypropylene (19.9 mg/m$\sp2)$ and polycarbonate (20.6 mg/m$\sp2)$; adsorption on PVDF and nylon were considerable less (1.44 mg/m$\sp2$ and 3.26 mg/m$\sp2,$ respectively). No effect of pore size was found in the adsorption isotherms. Fouling was characterized by the permeability of water and albumin solutions through membranes. The effect of adsorption on fouling was also quantified; a direct relation was found between the relative permeability of albumin solution and protein adsorption. A high adsorptive membrane had low relative permeability of albumin solution and a low adsorptive membrane had high relative permeability of albumin solution. For hydrophobic membranes, the high protein adsorption was responsible for low permeability of albumin solution. On the other hand, protein aggregation played a more dominant role for hydrophilic membranes. Low temperature plasma was used to modify the adsorption on the membranes. Tortuosity and thickness of membranes were important parameters for the surface modification to be effective. Protein adsorption decreased with increasing oxygen content in the feed gas for the n-butane/oxygen treatment, indicating the importance of hydrophobic interactions for albumin. For the oxygen plasma and the n-butane/oxygen plasma treatments, the protein adsorption was reduced by 96% and 73%, respectively. Correspondingly, the permeability of albumin solution increased by 91% and 89%, respectively. For practical use, the n-butane/oxygen plasma treatment may be a better alternative than oxygen plasma treatment because of the rotation of hydrophilic groups into the bulk polymer for the latter treatment. For the nitrogen and n-butane/nitrogen treatments, protein adsorption increased with increasing nitrogen content in the feedgas despite a decreasing contact angle, indicating that electrostatic interaction influenced the adsorption. The higher adsorption on the aminated membranes resulted in a reduction in relative permeability.
Download or read book Grafting of Stimuli responsive Polymer Films to Ultrafiltration Membranes written by Colleen Michelle Gorey and published by . This book was released on 2008 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project focused on modifying membrane surfaces to increase fouling control while improving permeability and selectivity, resulting in membranes with longer operational lives, lower cleaning frequencies, and higher efficiencies. The modifications involved the attachment of a temperature sensitive polymer to keep the membrane from fouling. The membrane modifications, which produced a self-cleaning cellulose acetate membrane, involved grafting the surface with a thermally responsive film layer of hydroxypropyl cellulose (HPC). HPC possesses a lower critical solution temperature (LCST) of approximately 43C. When attached to a surface, HPC forms a film, which collapses at temperatures above the LCST and expands when cooled to below the LCST. By keeping the film in a non-equilibrium state, via oscillating the temperature of the membrane surface, (as was observed by flux decline), fouling was reduced. Two surface modification techniques were tested and compared to the unmodified membrane - Method 1 and Method 2. Method 1 involved the attachment of a gel layer whereas Method 2 was the attachment of polymer structures on the surface of the membrane. Roughness measurements, using a wet atomic force microscopy (AFM) cell, and filtration experiments (to monitor flux declines) were performed at cold temperatures (25C), at hot temperatures (60C) and with temperature oscillations. The unmodified membrane had roughness values that were higher when hot and lower when cold, and it displayed flux declines under all temperature conditions when a humic solution was filtered. Since the humic solution was acting as a fouling agent, the decrease in flux indicated the membrane was fouling. When Method 1 was used, both roughness values and filtration experiments supported temperature activation. Wet Method 1 membranes at cold temperatures displayed an average roughness of 8.40 nm while at hot temperatures, the roughness decreased to 0.92 nm, supporting the hypothesis of the film being expanded at cold temperatures and collapsed at hot temperatures. Filtration experiments using the Method 1 membrane showed that flux measurements remained nearly constant at all temperature test conditions; however, initial flux values were significantly lower than the unmodified membrane due to the potential film formation within pores. On the other hand, the Method 2 showed higher initial flux values (not significantly different from the unmodified membrane) since the film was formed in solution then attached to the membrane, which was believed to be farther away from the membrane surface. Membrane roughness values for Method 2 were on average 6.80 nm and 5.02 nm for cold and hot temperatures. As with Method 1, Method 2 membranes displayed nearly no flux decline irrespective of temperature condition when a humic solution was filtered through. Even though temperature responses were more pronounced when Method 1 membranes were used as compared to the Method 2 membranes, the loss in initial fluxes due to pore blockage with Method 1 made Method 2 more advantageous. A Method 2 modified membrane would produce a self-cleaning membrane. The use of harsh chemicals during normal membrane cleaning would be avoided with the Method 2 modified membrane as a constant flux operation could be achieved using temperature oscillations only.
Download or read book Surface Modification and Biocompatibility Studies of Polyurethane Membranes written by Yeşim Özdemir and published by . This book was released on 2001 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fabrication and Photochemical Surface Modification of Photoreactive Thin film Composite Membranes and Model Development for Thin Film Formation by Interfacial Polymerization written by and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polymer Surface Modification by Adsorption from Supercritical Fluids written by Yong Chen and published by . This book was released on 2008 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reconstitution of Eukaryotic Membranes on Polymer Surface and Devices for Studies of Membrane Protein Biophysics written by Han-Yuan Liu and published by . This book was released on 2020 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: Membrane proteins are responsible for significant proportion of cellular functions and therefore, implicated in many diseases. For example, more than 60% of therapeutics to date target membrane proteins to alter cellular functions that lead to disease. Recent work has shown that the local membrane environment made up of specific lipids surrounding the protein may be critical in regulating their function. Over the past several decades, supported lipid bilayers (SLB) have emerged as a useful model membrane system to investigate these essential protein functions along with their lipid environment because they can be compatible with wide range of surface-based analytical techniques to quantitatively analyze the biological outcome. However, it is still challenging to capture membrane proteins in functional states along with the native components of the plasma membrane. In this thesis, I proposed a novel strategy to take native cell membrane vesicles budded directly from living cell plasma membranes as intermediates to incorporate the native lipids and proteins into SLB platforms, without suffering from the significant downsides of traditional detergent-based reconstitution. This strategy allows preservation of the complexity of the cell plasma membrane and retention of the natural protein structure and functionality. Another critical advance I introduced to this platform was integration of supporting surface that is a transparent, conductive polymeric material that not only supports the membrane to increase its robustness, but also is capable of reporting protein function as well. These polymeric materials can be tuned so their mechanical property mimics native tissues and these materials are biocompatible with cell membranes, while their cushioning ability mitigates the deleterious interaction from commonly used silica-based surfaces. Due to the merits of the conducting polymer, I developed a biomembrane-based organic electronic device combining the native lipid environment, functional membrane proteins, soft tissue like supporting surfaces, and an electroactive surface that acts as a sensor and reporter. Altogether, with such a device I have demonstrated a variety of biosensing applications including pathogen detection, antibiotic screening, ligand-receptor binding, lipid constituent detection, and, perhaps most significantly, ion channel monitoring. These ion channel receptors are important therapeutic targets for pain management, yet little is understood about how they actually work and furthermore, the role of the membrane in their functions. This new biosensing platform may prove to be a useful new approach for pharmaceutical screening and development, as well as basic science studies of ion channel regulation and biology.
