Strategy study of critical flux/threshold flux on alleviating protein fouling of PVDF-TiO2 modified membrane

Zwitterions show great superiority in the field of polymer membrane surface functionalization, as the synthesis process is simple, the adaptability of functional groups is strong, and zwitterions with strong hydration capacity in aqueous solutions can inhibit protein adsorption. In this study, a polyacrylonitrile ultrafiltration membrane was modified to improve anti-protein-fouling capacity by grafting short-chain sulfonic type zwitterions. 3-Dimethylaminopropylamine was first grafted onto hydrolyzed polyacrylonitrile (PAN) membrane by the activation of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC). Subsequently, sulfobetaine zwitterions emerged on the membrane surface by quaternization of 1,3-propane sultone. The sulfobetaine zwitterionic membranes were analyzed for surface chemical composition, hydrophilic properties, and surface and cross-sectional structure of the membrane, by a combination of Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact angle measurement, and scanning electron microscopy. Static protein adsorption and dynamic filtration experiments were undertaken to show that the modified membrane had excellent resistance to protein adsorption. It was found that the molecular weight cutoff of the substrate membrane had great influence on the flux recovery rate of the modified membrane.

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Studies of Protein Absorption and Fouling Behavior on Amphoteric Charged Polypropylene Microfiltration Membrane

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.467-469.2024 ◽

2011 ◽

Vol 467-469 ◽

pp. 2024-2029

Author(s):

Yan Jun Liu ◽

Chun Ying Lv ◽

Jia Yang

Keyword(s):

Zeta Potential ◽

Alkaline Solution ◽

Water Flux ◽

Polypropylene Membrane ◽

Protein Fouling ◽

Antifouling Property ◽

Wide Range ◽

Adsorption Amount ◽

Modified Membrane ◽

Charged Membranes

To improve the antifouling property of PP membrane, a series of amphoteric charged membranes was prepared by the introduction of cysteine on polypropylene membrane. The modified membrane presents higher water flux than original membrane due to the improved hydrophilicity. It was proved by zeta potential that modified membrane inherited the amphoteric characteristic from cysteine. The isoelectric point of modified membranes are at pH 7.2 and 6.5 for 7.6% and 16.1% grafted membranes respectively. Due to the amphoteric characteristic of both modified membrane and BSA, electrical repulsion exsists among grafting chains and BSA in acid and alkaline solution. As a result, modified membranes have much lower adsorption amount of BSA than original PP membrane. Moreover, modified membranes show obvious antifouling property to BSA, due to the improved hydrophilicity of membrane and the electrical repulsion between BSA and membrane. Therefore, the amphoteric charged membranes modified by cysteine show great potential to resist protein fouling in a wide range of pH.

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B3. Palestine Strategy Study Group, ““Regaining the Initiative: Palestinian Strategic Options to End Israeli Occupation,”” August 2008 (excerpts).

Journal of Palestine Studies ◽

10.1525/jps.2008.38.1.169 ◽

2008 ◽

Vol 38 (1) ◽

pp. 169-172

Keyword(s):

Study Group ◽

Strategy Study ◽

Strategic Options ◽

Israeli Occupation

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PENGARUH STRATEGI PEMBELAJARAN DAN MOTIVASI BERPRESTASI TERHADAP HASIL BELAJAR MATEMATIKA

JURNAL PENELITIAN BIDANG PENDIDIKAN ◽

10.24114/jpp.v18i3.4292 ◽

2012 ◽

Vol 18 (3) ◽

pp. 112

Author(s):

Rosliana Siregar

Keyword(s):

Achievement Motivation ◽

High Achievement ◽

Low Achievement ◽

Study Strategy ◽

Strategy Study ◽

Test Result ◽

Technique Analysis

This research aim to know of difference between result learn the studentmathematics taught by using strategy of study cooperative type STAD and result oflearning student mathematics by using strategy of study ekspositori. The method isquasi experiment. This research is executed SMP Negeri 11 Medan. Instrumentused together the data test result of learning and enquette motivate to haveachievement. Technique analysis the data used by ANAVA 2x2. The result analysisof research indicate that result learn the student mathematics taught by usingstrategy study of higher type STAD cooperative than result learn the studentmathematics taught by using strategy of study ekspositori (Fcalculate = 4,698 >Ftabel = 3,96; there are difference which signifikan of result learn the studentmathematics having high achievement motivation with the student having lowmotivation achievement, (Fcalculate = 27,9 > Ftabel = 3,96), and there areinteraction between study strategy and motivate to have achievement in influencingresult learn the student mathematics (Fcalculate = 12,45 > Ftabel = 3,96). Result ofinferential research that strategy study of better type STAD cooperative taught tostudent having motivation have high achievement and good study ekspositoristrategy used to student having motivation have low achievement and there areinteraction of study strategy and motivate the to have achievement.

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Clinical Features and Temporal Changes of RT-PCR and Chest CT in COVID-19 Pediatric Patients: A Diagnostic Strategy Study

SSRN Electronic Journal ◽

10.2139/ssrn.3582787 ◽

2020 ◽

Author(s):

Wei Xia ◽

Yu Guo ◽

Zhiyao Tian ◽

Yan Luo ◽

Daoyu Hu ◽

...

Keyword(s):

Clinical Features ◽

Pediatric Patients ◽

Temporal Changes ◽

Chest Ct ◽

Diagnostic Strategy ◽

Rt Pcr ◽

Strategy Study

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Biomedical Uses of Sulfobetaine-Based Zwitterionic Materials

Organic Materials ◽

10.1055/s-0040-1721741 ◽

2020 ◽

Vol 02 (04) ◽

pp. 342-357

Author(s):

Francesco Zaccarian ◽

Matthew B. Baker ◽

Matthew J. Webber

Keyword(s):

Biomedical Applications ◽

Foreign Body Reaction ◽

Inflammatory Responses ◽

Cellular Adhesion ◽

Review Of The Literature ◽

Future Prospects ◽

Protein Fouling ◽

Biomedical Device ◽

The Many ◽

Hydrophilic Coatings

Protein fouling can render a biomedical device dysfunctional, and also serves to nucleate the foreign body reaction to an implanted material. Hydrophilic coatings have emerged as a commonly applied route to combat interface-mediated complications and promote device longevity and limited inflammatory response. While polyethylene glycol has received a majority of the attention in this regard, coatings based on zwitterionic moieties have been more recently explored. Sulfobetaines in particular constitute one such class of zwitterions explored for use in mitigating surface fouling, and have been shown to reduce protein adsorption, limit cellular adhesion, and promote increased functional lifetimes and limited inflammatory responses when applied to implanted materials and devices. Here, we present a focused review of the literature surrounding sulfobetaine, beginning with an understanding of its chemistry and the methods by which it is applied to the surface of a biomedical device in molecular and polymeric forms, and then advancing to the many early demonstrations of function in a variety of biomedical applications. Finally, we provide some insights into the benefits and challenges presented by its use, as well as some outlook on the future prospects for using this material to improve biomedical device practice by addressing interface-mediated complications.

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Quantifying the influence of divalent cations mass transport on critical flux and organic fouling mechanism of forward osmosis membrane

Desalination ◽

10.1016/j.desal.2021.115146 ◽

2021 ◽

Vol 512 ◽

pp. 115146

Author(s):

Thanh-Tin Nguyen ◽

Rusnang Syamsul Adha ◽

Chulmin Lee ◽

Dong-Ho Kim ◽

In S. Kim

Keyword(s):

Mass Transport ◽

Divalent Cations ◽

Forward Osmosis ◽

Critical Flux ◽

Fouling Mechanism ◽

Organic Fouling

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Development of a new method to evaluate critical flux and system reliability based on particle properties in a membrane bioreactor

Chemosphere ◽

10.1016/j.chemosphere.2021.130763 ◽

2021 ◽

pp. 130763

Author(s):

Yongsun Jang ◽

Han-Shin Kim ◽

Jeong-Hoon Lee ◽

So-Young Ham ◽

Jeong-Hoon Park ◽

...

Keyword(s):

System Reliability ◽

Membrane Bioreactor ◽

New Method ◽

Critical Flux ◽

Particle Properties

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Applying a Hydrophilic Modified Hollow Fiber Membrane to Reduce Fouling in Artificial Lungs

Separations ◽

10.3390/separations8080113 ◽

2021 ◽

Vol 8 (8) ◽

pp. 113

Author(s):

Nawaf Alshammari ◽

Meshari Alazmi ◽

Vajid Nettoor Veettil

Keyword(s):

Gas Exchange ◽

Hollow Fiber ◽

Hollow Fiber Membrane ◽

Membrane Surface ◽

Artificial Lung ◽

Hollow Fiber Membranes ◽

Fiber Membrane ◽

Hydrophilic Modification ◽

Protein Fouling ◽

Time Periods

Membranes for use in high gas exchange lung applications are riddled with fouling. The goal of this research is to create a membrane that can function in an artificial lung until the actual lung becomes available for the patient. The design of the artificial lung is based on new hollow fiber membranes (HFMs), due to which the current devices have short and limited periods of low fouling. By successfully modifying membranes with attached peptoids, low fouling can be achieved for longer periods of time. Hydrophilic modification of porous polysulfone (PSF) membranes can be achieved gradually by polydopamine (PSU-PDA) and peptoid (PSU-PDA-NMEG5). Polysulfone (PSU-BSA-35Mg), polysulfone polydopamine (PSUPDA-BSA-35Mg) and polysulfone polydopamine peptoid (PSU-PDA-NMEG5-BSA35Mg) were tested by potting into the new design of gas exchange modules. Both surfaces of the modified membranes were found to be highly resistant to protein fouling permanently. The use of different peptoids can facilitate optimization of the low fouling on the membrane surface, thereby allowing membranes to be run for significantly longer time periods than has been currently achieved.

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