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Fedalto L, de Oliveira PR, Agustini D, Kalinke C, Banks CE, Bergamini MF, Marcolino-Junior LH. Novel and highly stable strategy for the development of microfluidic enzymatic assays based on the immobilization of horseradish peroxidase (HRP) into cotton threads. Talanta 2022; 252:123889. [DOI: 10.1016/j.talanta.2022.123889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/08/2022] [Accepted: 08/24/2022] [Indexed: 10/15/2022]
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Rather AH, Khan RS, Wani TU, Beigh MA, Sheikh FA. Overview on immobilization of enzymes on synthetic polymeric nanofibers fabricated by electrospinning. Biotechnol Bioeng 2021; 119:9-33. [PMID: 34672360 DOI: 10.1002/bit.27963] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 09/07/2021] [Accepted: 10/13/2021] [Indexed: 01/19/2023]
Abstract
The arrangement and type of support has a significant impact on the efficiency of immobilized enzymes. 1-dimensional fibrous materials can be one of the most desirable supports for enzyme immobilization. This is due to their high surface area to volume ratio, internal porosity, ease of handling, and high mechanical stability, all of which allow a higher enzyme loading, release and finally lead to better catalytic efficiency. Fortunately, the enzymes can reside inside individual nanofibers to remain encapsulated and retain their three-dimensional structure. These properties can protect the enzyme's tolerance against harsh conditions such as pH variations and high temperature, and this can probably enhance the enzyme's stability. This review article will discuss the immobilization of enzymes on synthetic polymers, which are fabricated into nanofibers by electrospinning. This technique is rapidly gaining popularity as one of the most practical ways to fibricate polymer, metal oxide, and composite micro or nanofibers. As a result, there is interest in using nanofibers to immobilize enzymes. Furthermore, present research on electrospun nanofibers for enzyme immobilization is primarily limited to the lab scale and industrial scale is still challanging. The primary future research objectives of this paper is to investigate the use of electrospun nanofibers for enzyme immobilization, which includes increasing yield to transfer biological products into commercial applications.
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Affiliation(s)
- Anjum Hamid Rather
- Department of Nanotechnology, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, India
| | - Rumysa Saleem Khan
- Department of Nanotechnology, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, India
| | - Taha Umair Wani
- Department of Nanotechnology, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, India
| | - Mushtaq A Beigh
- Department of Nanotechnology, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, India
| | - Faheem A Sheikh
- Department of Nanotechnology, University of Kashmir, Hazratbal, Srinagar, Jammu and Kashmir, India
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Vineh MB, Saboury AA, Poostchi AA, Ghasemi A. Biodegradation of phenol and dyes with horseradish peroxidase covalently immobilized on functionalized RGO-SiO 2 nanocomposite. Int J Biol Macromol 2020; 164:4403-4414. [PMID: 32931826 DOI: 10.1016/j.ijbiomac.2020.09.045] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/05/2020] [Accepted: 09/08/2020] [Indexed: 01/06/2023]
Abstract
Horseradish peroxidase (HRP) was immobilized onto a functionalized reduced graphene oxide-SiO2 through the covalent bonding process. By using scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR), the formed nanocomposites were characterized. The kinetic parameters including the catalytic constant, kcat, and the catalytic efficiency, kcat/Km, increased 5.5 and 6 times, respectively, after immobilization. The circular dichroism analysis demonstrated that the α-helical content increased from 39% to 46% after immobilization. The immobilization improved the reusability of HRP as 70% of initial activity retained after 10 cycles. Due to the buffering effect, the immobilized HRP was less sensitive to pH changes as compared to the free HRP. At temperature 40 °C and during 90 min, the immobilized HRP retained 90% of the initial activity while 70% of initial activity remained for the free HRP. After 35-day storage, no reduction in the activity was observed for the immobilized HRP. The removal efficiency for phenol concentration (2500 mg/L) obtained 100% and 50% for the immobilized and free HRP, respectively. The results showed that the immobilized HRP promoted the dyes decolorization from 2-fold until 26-fold as compared to the free HRP. The decolorization efficiencies reached 100% for most dyes in the case of immobilized HRP.
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Affiliation(s)
- Monireh Besharati Vineh
- Young Researchers and Elite Club, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran
| | - Ali Akbar Saboury
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran; Center of Excellence in Biothermodynamics, University of Tehran, Tehran, Iran.
| | - Amir Ali Poostchi
- Petrochemical Industries Development Management Company (PIDMCO), P.O. Box 15858-49568, Tehran, Iran
| | - Atiyeh Ghasemi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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Pinem J, Wardani A, Aryanti P, Khoiruddin K, Wenten IG. Hydrophilic Modification of Polymeric Membrane using Graft Polymerization Method: A Mini Review. ACTA ACUST UNITED AC 2019. [DOI: 10.1088/1757-899x/547/1/012054] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sahu S, Shera SS, Banik RM. Enhanced Reusability of Horseradish Peroxidase Immobilized onto Graphene Oxide/Magnetic Chitosan Beads for Cost Effective Cholesterol Oxidase Assay. ACTA ACUST UNITED AC 2019. [DOI: 10.2174/1874070701913010093] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:Horseradish Peroxidase (HRP) is an important biocatalyst extensively used in enzymatic reactions. Cholesterol oxidase (ChoX) is a commercially valuable enzyme used in the estimation of cholesterol in human serum. ChoX is an oxygen oxidoreductase class of enzyme which catalyzes the oxidation of cholesterol in the presence of O2, liberating hydrogen peroxide H2O2as a by-product. HRP catalyzes the reduction of this H2O2in the presence of a redox dye (chromophore), producing a pink colored Quinoneimine which can be measured spectrophotometrically. The use of soluble HRP makes this assay method expensive for each time use and the recovery of HRP is not possible.Objective:Our aim was to prepare the HRP immobilized beads having magnetic properties for the ease of separation and increasing the reusability of HRP for the low cost ChoX assay.Methods:In the present work, we prepared magnetic chitosan beads using chitosan-Fe2O3nanoparticle blend coated with Graphene Oxide (GO), and subsequently activated with 2.5% glutaraldehyde (GA). Enzyme loaded beads were characterized by SEM, FTIR, and XRD analysis.Results:The immobilization efficiency was ~80% and the immobilized HRP retained 90% of its initial activity up to 12 times reuse. The pH and temperature optima were shifted from 6.5 and 50°C for soluble HRP to 7.0 and 55°C for the immobilized HRP, respectively. Storage stability of immobilized HRP was 93.72% and 60.97% after 30 and 60 days storage respectively, at 4°C.Conclusion:On the basis of the present study, the HRP loaded magnetic chitosan/graphene oxide beads could be used for low-cost ChoX assay at laboratory scale due to its enhanced reusability and stability.
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Almulaiky YQ, Al-Harbi SA. A novel peroxidase from Arabian balsam (Commiphora gileadensis) stems: Its purification, characterization and immobilization on a carboxymethylcellulose/Fe3O4 magnetic hybrid material. Int J Biol Macromol 2019; 133:767-774. [DOI: 10.1016/j.ijbiomac.2019.04.119] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/09/2019] [Accepted: 04/16/2019] [Indexed: 01/11/2023]
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Xie X, Luo P, Han J, Chen T, Wang Y, Cai Y, Liu Q. Horseradish peroxidase immobilized on the magnetic composite microspheres for high catalytic ability and operational stability. Enzyme Microb Technol 2019; 122:26-35. [DOI: 10.1016/j.enzmictec.2018.12.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 01/10/2023]
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Besharati Vineh M, Saboury AA, Poostchi AA, Rashidi AM, Parivar K. Stability and activity improvement of horseradish peroxidase by covalent immobilization on functionalized reduced graphene oxide and biodegradation of high phenol concentration. Int J Biol Macromol 2018; 106:1314-1322. [DOI: 10.1016/j.ijbiomac.2017.08.133] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 08/22/2017] [Accepted: 08/23/2017] [Indexed: 10/19/2022]
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Arica MY, Salih B, Celikbicak O, Bayramoglu G. Immobilization of laccase on the fibrous polymer-grafted film and study of textile dye degradation by MALDI–ToF-MS. Chem Eng Res Des 2017. [DOI: 10.1016/j.cherd.2017.09.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Konovalova V, Guzikevich K, Burban A, Kujawski W, Jarzynka K, Kujawa J. Enhanced starch hydrolysis using α-amylase immobilized on cellulose ultrafiltration affinity membrane. Carbohydr Polym 2016; 152:710-717. [PMID: 27516322 DOI: 10.1016/j.carbpol.2016.07.065] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/10/2016] [Accepted: 07/17/2016] [Indexed: 01/10/2023]
Abstract
In order to prepare ultrafiltration membranes possessing biocatalytic properties, α-amylase has been immobilized on cellulose membranes. Enzyme immobilization was based on a covalent bonding between chitosan and a surface of cellulose membrane, followed by an attachment of Cibacron Blue F3G-A dye as affinity ligand. Various factors affecting the immobilization process, such as enzyme concentration, pH of modifying solution, zeta-potential of membrane surface, and stability of immobilized enzyme were studied. The applicability of immobilized α-amylase has been investigated in ultrafiltration processes. The immobilization of α-amylase on membrane surface allows to increase the value of mass transfer coefficient and to decrease the concentration polarization effect during ultrafiltration of starch solutions. The enzyme layer on the membrane surface prevents a rapid increase of starch concentration due to the amylase hydrolysis of starch in the boundary layer. The presented affinity immobilization technique allows also for the regeneration of membranes from inactivated enzyme.
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Affiliation(s)
- Viktoriia Konovalova
- Department of Chemistry, National University of Kyiv-Mohyla Academy, 2 Skovoroda Street, 04070 Kiev, Ukraine
| | - Kateryna Guzikevich
- Department of Chemistry, National University of Kyiv-Mohyla Academy, 2 Skovoroda Street, 04070 Kiev, Ukraine
| | - Anatoliy Burban
- Department of Chemistry, National University of Kyiv-Mohyla Academy, 2 Skovoroda Street, 04070 Kiev, Ukraine
| | - Wojciech Kujawski
- Nicolaus Copernicus University in Toruń, Faculty of Chemistry, 7 Gagarina Street, 87-100 Toruń, Poland.
| | - Karolina Jarzynka
- Nicolaus Copernicus University in Toruń, 11 Gagarina Street, 87-100 Toruń, Poland
| | - Joanna Kujawa
- Nicolaus Copernicus University in Toruń, Faculty of Chemistry, 7 Gagarina Street, 87-100 Toruń, Poland
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Wang S, Liu W, Zheng J, Xu X. Immobilization of horseradish peroxidase on modified PAN-based membranes for the removal of phenol from buffer solutions. CAN J CHEM ENG 2016. [DOI: 10.1002/cjce.22469] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Shuai Wang
- College of Chemistry; Fuzhou University; Fuzhou 350108 China
| | - Wei Liu
- College of Chemistry; Fuzhou University; Fuzhou 350108 China
| | - Jinwang Zheng
- Shanghai Tofflon Science and Technology Co., Ltd.; Shanghai 200000 China
| | - Xiaoping Xu
- College of Chemistry; Fuzhou University; Fuzhou 350108 China
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Affiliation(s)
- Goran T. Vladisavljević
- Chemical Engineering Department, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK
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Demirci N, Demirel M, Dilsiz N. Surface Modification of PVC Film with Allylamine Plasma Polymers. ADVANCES IN POLYMER TECHNOLOGY 2014. [DOI: 10.1002/adv.21435] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nagihan Demirci
- Department of Chemical Engineering; Gazi University; Maltepe Ankara 06570 Turkey
| | - Miyaser Demirel
- Department of Chemical Engineering; Gazi University; Maltepe Ankara 06570 Turkey
| | - Nursel Dilsiz
- Department of Chemical Engineering; Gazi University; Maltepe Ankara 06570 Turkey
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Yan D, Guo C, Xu X, Ma G, Sheng J. Reaction kinetics studies on plasma-treated polypropylene-polystyrene interfaces. J Appl Polym Sci 2012. [DOI: 10.1002/app.36892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Caramori SS, Fernandes KF, de Carvalho Junior LB. Immobilized horseradish peroxidase on discs of polyvinyl alcohol-glutaraldehyde coated with polyaniline. ScientificWorldJournal 2012; 2012:129706. [PMID: 22619582 PMCID: PMC3349093 DOI: 10.1100/2012/129706] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 12/11/2011] [Indexed: 11/17/2022] Open
Abstract
Discs of network polyvinyl alcohol-glutaraldehyde (PVAG) were synthesized and coated with polyaniline (PANI) using glutaraldehyde as a chemical arm (PVAG-PANIG-HRP disc). The best conditions for the immobilization were established as about 1.0 mg mL(-1) of protein, for 60 min and pH 5.5. The soluble enzyme lost all of its activity after incubation at 70°C for 15 min, whereas the PVAG-PANIG-HRP disc retained about half of the initial activity for pyrogallol. The same PVAG-PANIG-HRP disc was used consecutively three times without any activity lossbut presented 25% of the initial activity after the 7th use. PVAG-PANIG-HRP disc retained approximately 80% and 60% of its initial activity after 60 and 80 days of storage, respectively. Resorcinol, m-cresol, catechol, pyrogallol, α-naphthol, βnaphthol, and 4, 4'-diaminodiphenyl benzidine were efficiently oxidized by the PVAG-PANIG-HRP disc (from about 70% to 90%), and it was less efficient towards aniline, phenol, and 2-nitrosonaphthol.
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Affiliation(s)
- Samantha Salomão Caramori
- Unidade Universitária de Ciências Exatas e Tecnológicas, Universidade Estadual de Goiás, Caixa Postal 459, Rodovia BR 153, Km 9875132-903 Anápolis, GO, Brazil.
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Enzymatic activation of cellulose acetate membrane for reducing of protein fouling. Colloids Surf B Biointerfaces 2012; 92:334-9. [DOI: 10.1016/j.colsurfb.2011.12.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Revised: 12/07/2011] [Accepted: 12/08/2011] [Indexed: 11/24/2022]
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Chemical and Physical Modifications of Biomaterial Surfaces to Control Adhesion of Cells. ACTA ACUST UNITED AC 2010. [DOI: 10.1007/978-90-481-8790-4_13] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Gabrovska K, Godjevargova T. Optimum immobilization of urease on modified acrylonitrile copolymer membranes: Inactivation by heavy metal ions. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/j.molcatb.2009.03.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gan S, Yang P, Yang W. Photoactivation of alkyl C-H and silanization: a simple and general route to prepare high-density primary amines on inert polymer surfaces for protein immobilization. Biomacromolecules 2009; 10:1238-43. [PMID: 19317482 DOI: 10.1021/bm900011h] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Surface modification through implanting functional groups has been demonstrated to be extremely important to biomedical applications. The usage of organic polymer phase is often required to achieve satisfactory results. However, organic surfaces usually have poor chemical reactivity toward other reactants and target biomolecules because these surfaces usually only consist of simple alkyl (C-H) and/or alkyl ether (ROR') structures. For the first time, we here report the potential to perform silanization techniques on alkyl polymer surface, which provide a simple, fast, inexpensive, and general method to decorate versatile functional groups at the molecular level. As an example, high-density primary amines could be obtained on a model polymer, polypropylene substrate, through the reaction between amine-capped silane, 3-aminopropyltriethoxysilane (APTES) and hydroxylated polypropylene surface. A model protein, immunoglobulin (IgG), could be effectively immobilized on the surface after transforming amines to aldehydes by the aldehyde-amine condensation reaction between glutaraldehyde (GA) and amines. The routes we report here could directly make use of the benefits from well-developed silane chemistry, and hereby are capable of grafting any functionalities on inert alkyl surfaces via changing the terminal groups in silanes, which should instantly stimulate the development of many realms such as microarrays, immunoassays, biosensors, filtrations, and microseparation.
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Affiliation(s)
- Shenghua Gan
- The State Key Laboratory of Chemical Resource Engineering, Beijing, 100029, China
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Ghasemi M, Minier M, Tatoulian M, Arefi-Khonsari F. Determination of amine and aldehyde surface densities: application to the study of aged plasma treated polyethylene films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:11554-61. [PMID: 17915893 DOI: 10.1021/la701126t] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The aim of this work was to test and to compare different methods reported in the literature to quantify amine and aldehyde functions on the surface of polyethylene (PE) films treated by ammonia plasma and to specify their stability against time. A low pressure ammonia plasma reactor was used to functionalize PE films with amine groups, which could be subsequently used for further immobilization of biomolecules. In order to determine the density of amine groups on the surface of treated films, various molecule probes and spectrophotometric analytical methods have been investigated. Two methods using (i) sulfosuccinimidyl 6-[3'-(2-pyridyldithio)-propionamido] hexanoate (sulfo-LC-SPDP) and (ii) 2-iminothiolane (ITL) associated with bicinchoninic acid (BCA) have been proved to be reliable and sensitive enough to estimate the surface concentration of primary amine functions. The amount of primary amino groups on the functionalized polyethylene films was found to be between 1.2 and 1.4 molecules/nm2. In a second step, the surface concentration of glutaraldehyde (GA), which is currently used as a spacer arm before immobilization of biomolecules, has been assessed: two methods were used to determine the surface density of available aldehyde functions, after the reaction of GA with the aminated polyethylene film. The concentration of GA was found to be in the same range as primary amine concentration. The influence of aging time on the density of available amino and aldehyde groups on the surfaces were evaluated under different storage conditions. The results showed that 50% of the initial density of primary amine functions remained available after storage during 6 days of the PE samples in PBS (pH 7.6) at 4 degrees C. In the case of aldehyde groups, the same percentage of the initial density (50%) remained active after storage in air at RT over a longer period, i.e., 15 days.
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Affiliation(s)
- Mahsa Ghasemi
- Ecole Nationale Supérieure de Chimie de Paris, Laboratoire de Génie des Procédés Plasma et Traitements de Surface, 11 rue Pierre et Marie Curie, 75231 Paris Cedex France.
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Yang Q, Tian J, Hu MX, Xu ZK. Construction of a comb-like glycosylated membrane surface by a combination of UV-induced graft polymerization and surface-initiated ATRP. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:6684-90. [PMID: 17497813 DOI: 10.1021/la700275t] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Carbohydrate residues are found on the extracellular side of the cell membrane. They form a protective coating on the outer surface of the cell and are involved in intercellular recognition. Synthetic carbohydrate-based polymers, so-called glycopolymers, are emerging as important well-defined tools for investigating carbohydrate-based biological processes and for simulating various functions of carbohydrates. In this work, the surface of a polypropylene microporous membrane (PPMM) was modified with comb-like glycopolymer brushes by a combination of UV-induced graft polymerization and surface-initiated atom-transfer radical polymerization (ATRP). 2-Hydroxyethyl methacrylate (HEMA) was first grafted to the PPMM surface under UV irradiation in the presence of benzophenone and ferric chloride. ATRP initiator was then coupled to the hydroxyl groups of poly(HEMA) brushes. Surface-initiated ATRP of a glycomonomer, D-gluconamidoethyl methacrylate, was followed at ambient temperature in aqueous solvent. Water had a significant acceleration effect on the ATRP process; however, loss of control over the polymerization process was also observed. The addition of CuBr2 to the ATRP system largely increased the controllability at the cost of the polymerization rate. The grafting of HEMA, the coupling of ATRP initiator to the hydroxyl groups, and the surface-initiated ATRP were confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.
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Affiliation(s)
- Qian Yang
- Institute of Polymer Science, Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education, and State Key Laboratory of Chemical Engineering, Zhejiang University, Hangzhou 310027, PR China
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Wang ZG, Ke BB, Xu ZK. Covalent immobilization of redox enzyme on electrospun nonwoven poly(acrylonitrile-co-acrylic acid) nanofiber mesh filled with carbon nanotubes: A comprehensive study. Biotechnol Bioeng 2006; 97:708-20. [PMID: 17171660 DOI: 10.1002/bit.21280] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In this work, novel conductive composite nanofiber mesh possessing reactive groups was electrospun from solutions containing poly(acrylonitrile-co-acrylic acid) (PANCAA) and multi-walled carbon nanotubes (MWCNTs) for redoxase immobilization, assuming that the incorporated MWCNTs could behave as electrons transferor during enzyme catalysis. The covalent immobilization of catalase from bovine liver on the neat PANCAA nanofiber mesh or the composite one was processed in the presence of EDC/NHS. Results indicated that both the amount and activity retention of bound catalase on the composite nanofiber mesh were higher than those on the neat PANCAA nanofiber mesh, and the activity increased up to 42%. Kinetic parameters, K(m) and V(max), for the catalases immobilized on the composite nanofiber mesh were lower and higher than those on the neat one, respectively. This enhanced activity might be ascribed to either promoted electron transfer through charge-transfer complexes and the pi system of carbon nanotubes or rendered biocompatibility by modified MWCNTs. Furthermore, the immobilized catalases revealed much more stability after MWCNTs were incorporated into the polymer nanofiber mesh. However, there was no significant difference in optimum pH value and temperature, thermal stability and operational stability between these two immobilized preparations, while the two ones appeared more advantageous than the free in these properties. The effect of MWCNTs incorporation on another redox enzyme, peroxidase, was also studied and it was found that the activity increased by 68% in comparison of composite one with neat preparation.
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Affiliation(s)
- Zhen-Gang Wang
- Institute of Polymer Science, and Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education), Zhejiang University, Hangzhou 310027, PR China
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