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Use of Engineered Nanoparticles (ENPs) for the Study of High-Affinity IgE FcεRI Receptor Engagement and Rat Basophilic Leukemia (RBL) Cell Degranulation. Methods Mol Biol 2020. [PMID: 32766975 DOI: 10.1007/978-1-0716-0696-4_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Degranulation of mast cells and basophils occurs after the cross-linking of FcεRI receptor-bound IgE by multivalent allergens, resulting in the release of a range of de novo synthesized and preformed mediators of the allergic response. β-Hexosaminidase release is usually measured as a simple readout for degranulation. Furthermore, the rat basophilic leukemia (RBL)-2H3 cell line is commonly used for measuring degranulation, monitoring β-hexosaminidase release. Here, we describe surface-engineered and modified nanoparticles with specific ligands in order to study the signaling and cellular responses of the RBL-2H3 cell line.
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Khakalo A, Filpponen I, Rojas OJ. Protein Adsorption Tailors the Surface Energies and Compatibility between Polylactide and Cellulose Nanofibrils. Biomacromolecules 2017; 18:1426-1433. [PMID: 28287713 DOI: 10.1021/acs.biomac.7b00173] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The state of dispersion and the interactions between a polymer and a filler in a nanocomposite crucially define its properties and performance. The affinity of polylactide (PLA) with vegetable and animal proteins (casein, gelatin, soy protein isolate, and hydrolysate) is investigated and their role as eco-friendly dispersants and compatibilizers of cellulose nanofibrils (CNF) is elucidated. The affinity of the proteins with PLA is determined by using sensograms acquired by electroacoustic (quartz crystal microgravimetry) and optical (surface plasmon resonance) techniques. The surface energy of PLA increases upon protein adsorption while the opposite effect is observed for CNF, under identical experimental conditions. A significant improvement in the thermodynamic work of adhesion for PLA/CNF systems is predicted by application of the denatured proteins at low concentrations (∼20% and ∼15% enhancement with soy protein and casein at pH 3 and pH 8, respectively). We offer a robust method to screen denatured proteins and to tailor the wettability and material compatibility in the synthesis of bionanocomposites based on CNF and PLA.
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Affiliation(s)
- Alexey Khakalo
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University , FI-00076, Espoo, Finland
| | - Ilari Filpponen
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University , FI-00076, Espoo, Finland.,Alabama Center for Paper and Bioresource Engineering, Department of Chemical Engineering, Auburn University , Auburn, Alabama 36849-5127, United States
| | - Orlando J Rojas
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University , FI-00076, Espoo, Finland.,Departments of Chemical and Bimolecular Engineering, North Carolina State University , Raleigh, North Carolina 27695, United States
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Khakalo A, Filpponen I, Johansson LS, Vishtal A, Lokanathan AR, Rojas OJ, Laine J. Using gelatin protein to facilitate paper thermoformability. REACT FUNCT POLYM 2014. [DOI: 10.1016/j.reactfunctpolym.2014.09.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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4
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Guha S, Wayment JR, Li M, Tarlov MJ, Zachariah MR. Protein adsorption–desorption on electrospray capillary walls – No influence on aggregate distribution. J Colloid Interface Sci 2012; 377:476-84. [DOI: 10.1016/j.jcis.2012.03.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 03/19/2012] [Accepted: 03/20/2012] [Indexed: 02/02/2023]
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5
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Guha S, Wayment JR, Li M, Tarlov MJ, Zachariah MR. Characterizing the adsorption of proteins on glass capillary surfaces using electrospray-differential mobility analysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:13008-13014. [PMID: 21905703 DOI: 10.1021/la202792g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We quantify the adsorption and desorption of a monoclonal immunoglobulin-G antibody, rituxamab (RmAb), on silica capillary surfaces using electrospray-differential mobility analysis (ES-DMA). We first develop a theory to calculate coverages and desorption rate constants from the ES-DMA data for proteins adsorbing on glass capillaries used to electrospray protein solutions. This model is then used to study the adsorption of RmAb on a bare silica capillary surface. A concentration-independent coverage of ≈4.0 mg/m(2) is found for RmAb concentrations ranging from 0.01 to 0.1 mg/mL. A study of RmAb adsorption to bare silica as a function of pH shows maximum adsorption at its isoelectric point (pI of pH 8.5) consistent with literature. The desorption rate constants are determined to be ≈10(-5) s(-1), consistent with previously reported values, thus suggesting that shear forces in the capillary may not have a considerable effect on desorption. We anticipate that this study will allow ES-DMA to be used as a "label-free" tool to study adsorption of oligomeric and multicomponent protein systems onto fused silica as well as other surface modifications.
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Affiliation(s)
- Suvajyoti Guha
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, United States
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Gaihre B, Hee Lee Y, Khil MS, Yi HK, Kim HY. In-vitro cytotoxicity and cell uptake study of gelatin-coated magnetic iron oxide nanoparticles. J Microencapsul 2011; 28:240-7. [PMID: 21545315 DOI: 10.3109/02652048.2011.557747] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The aim of this study was to modify the surfaces of magnetic iron oxide nanoparticles (IOPs) with gelatin in order to reduce cytotoxicity and enhance cellular uptake. The gelatin-coated IOPs were characterized in terms of their functionalization, size, surface charge, morphology and crystalline structure using Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), dynamic light scattering (DLS), transmission electron microscopy (BIO-TEM) and x-ray diffraction (XRD) analysis. The cytotoxicity of the gelatin-coated IOPs to human fibroblasts was assessed using an MTT-assay and was compared with uncoated IOPs. Similarly, the cellular uptake of the coated and uncoated IOPs was visualized using BIO-TEM and quantified using inductively coupled plasma spectroscopy (ICPS). As shown by the Fourier emission scanning electron microscopy (FE-SEM) and viability test, the massive uptake of uncoated IOPs lead to reduced viability. However, gelatin coating lead to increased viability and slow uptake without any visible distortion to the cell morphology.
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Affiliation(s)
- Babita Gaihre
- Department of Bionanosystem Engineering, Chonbuk National University, Chonju, Republic of Korea.
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7
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Mavrakis C, Kiosseoglou V. The structural characteristics and mechanical properties of biopolymer/mastic gum microsized particles composites. Food Hydrocoll 2008. [DOI: 10.1016/j.foodhyd.2007.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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8
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Gaihre B, Parajuli DC, Seo HC, Khil MS, Kim HY. Effect of Different Parameters on Gelatin Adsorption and Stability of the Colloidal Dispersion of Gelatin-Coated Magnetic Iron Oxide Nano-Particles. ADSORPT SCI TECHNOL 2008. [DOI: 10.1260/026361708786934406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Affiliation(s)
- Babita Gaihre
- Department of Bionano System Engineering, Chonbuk National University, Chonju 561-756, Republic of Korea
| | - Daman C. Parajuli
- Department of Bionano System Engineering, Chonbuk National University, Chonju 561-756, Republic of Korea
| | - Hae C. Seo
- Department of Textile Engineering, Chonbuk National University, Chonju 561-756, Republic of Korea
| | - Myung S. Khil
- Center for Healthcare Technology Development, Chonbuk National University, Chonju 561-756, Republic of Korea
- Department of Textile Engineering, Chonbuk National University, Chonju 561-756, Republic of Korea
| | - Hak Y. Kim
- Center for Healthcare Technology Development, Chonbuk National University, Chonju 561-756, Republic of Korea
- Department of Textile Engineering, Chonbuk National University, Chonju 561-756, Republic of Korea
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Nizri G, Lagerge S, Kamyshny A, Major DT, Magdassi S. Polymer-surfactant interactions: binding mechanism of sodium dodecyl sulfate to poly(diallyldimethylammonium chloride). J Colloid Interface Sci 2008; 320:74-81. [PMID: 18255091 DOI: 10.1016/j.jcis.2008.01.016] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2007] [Revised: 01/10/2008] [Accepted: 01/11/2008] [Indexed: 10/22/2022]
Abstract
The binding mechanism of poly(diallyldimethylammonium chloride), PDAC, and sodium dodecyl sulfate, SDS, has been comprehensively studied by combining binding isotherms data with microcalorimetry, zeta potential, and conductivity measurements, as well as ab initio quantum mechanical calculations. The obtained results demonstrate that surfactant-polymer interaction is governed by both electrostatic and hydrophobic interactions, and is cooperative in the presence of salt. This binding results in the formation of nanoparticles, which are positively or negatively charged depending on the molar ratio of surfactant to PDAC monomeric units. From microcalorimetry data it was concluded that the exothermic character of the interaction diminishes with the increase in the surfactant/polymer ratio as well as with an increase in electrolyte concentration.
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Affiliation(s)
- Gilat Nizri
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Lin Y, Chen X, Jing X, Jiang Y, Su Z. Gelatin multilayers assembled on poly(L-lactic acid) surface for better cytocompatibility. J Appl Polym Sci 2008. [DOI: 10.1002/app.28174] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Lin Y, Wang L, Zhang P, Wang X, Chen X, Jing X, Su Z. Surface modification of poly(L-lactic acid) to improve its cytocompatibility via assembly of polyelectrolytes and gelatin. Acta Biomater 2006; 2:155-64. [PMID: 16701873 DOI: 10.1016/j.actbio.2005.10.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Revised: 09/27/2005] [Accepted: 10/19/2005] [Indexed: 11/30/2022]
Abstract
Poly(L-lactide) (PLLA) surface was modified via aminolysis by poly(allylamine hydrochloride) (PAH) at high pH and subsequent electrostatic self-assembly of poly(sodium styrenesulfonate) (PSS) and PAH, and the process was monitored by X-ray photoelectron spectroscopy (XPS) and contact angle measurement. These modified PLLAs were then used as charged substrates for further incorporation of gelatin to improve their cytocompatibility. The amphoteric nature of the gelatin was exploited and the gelatin was adsorbed to the negatively charged PLLA/PSS and positively charged PLLA/PAH at pH=3.4 and 7.4, respectively. XPS and water contact angle data indicated that the gelatin adsorption at pH=3.4 resulted in much higher surface coverage by gelatin than at pH=7.4. All the modified PLLA surfaces became more hydrophilic than the virgin PLLA. Chondrocyte culture was used to test the cell attachment, cell morphology and cell viability on the modified PLLA substrates. The results showed that the PAH and PSS modified PLLA exhibited better cytocompatibility than virgin PLLA, and the incorporation of the gelatin on these modified PLLA substrates further improved their cytocompatibility, with the PLLA/PSS substrate treated with the gelatin at pH=3.4 being the best, exceeding the chondrocyte compatibility of the tissue culture polystyrene.
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Affiliation(s)
- Yuan Lin
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun, Jilin 130022, China
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Shen D, Huang M, Wang F, Yang M. Impedance analysis of an electrode-separated piezoelectric sensor as a surface-monitoring technique for gelatin adsorption on quartz surface. J Colloid Interface Sci 2005; 281:398-409. [PMID: 15571695 DOI: 10.1016/j.jcis.2004.08.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2004] [Accepted: 08/11/2004] [Indexed: 11/30/2022]
Abstract
The early events pertaining to gelatin adsorption and desorption onto quartz surfaces were studied, employing an electrode-separated piezoelectric sensor (ESPS). The adsorption of gelatin on a quartz crystal surface corresponds to a mass increase, which can be monitored in real time by the changes in the impedance parameters of the ESPS. It was shown that the adsorption of gelatin on a quartz surface is partly irreversible with respect to the dilution of the bulk phase. The observed adsorption kinetics is compatible with a mechanism that involves adsorption, desorption, and transformation from a reversible adsorption state to irreversible one. A progressive approach method was established to simulate the adsorption process. The adsorption densities and kinetic parameters in the early adsorption process were obtained from the responses of the ESPS in the adsorption process. The influence of pH and ionic strength was tested. A comparison with the Langmuir adsorption model was made.
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Affiliation(s)
- Dazhong Shen
- School of Chemistry, Chemical Engineering and Material Science, Shandong Normal University, Jinan 250014, People's Republic of China.
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Zhou C, Friedt JM, Angelova A, Choi KH, Laureyn W, Frederix F, Francis LA, Campitelli A, Engelborghs Y, Borghs G. Human immunoglobulin adsorption investigated by means of quartz crystal microbalance dissipation, atomic force microscopy, surface acoustic wave, and surface plasmon resonance techniques. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:5870-8. [PMID: 16459603 DOI: 10.1021/la036251d] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Time-resolved adsorption behavior of a human immunoglobin G (hIgG) protein on a hydrophobized gold surface is investigated using multitechniques: quartz crystal microbalance/dissipation (QCM-D) technique; combined surface plasmon resonance (SPR) and Love mode surface acoustic wave (SAW) technique; combined QCM-D and atomic force microscopy (AFM) technique. The adsorbed hIgG forms interfacial structures varying in organization from a submonolayer to a multilayer. An "end-on" IgG orientation in the monolayer film, associated with the surface coverage results, does not corroborate with the effective protein thickness determined from SPR/SAW measurements. This inconsistence is interpreted by a deformation effect induced by conformation change. This conformation change is confirmed by QCM-D measurement. Combined SPR/SAW measurements suggest that the adsorbed protein barely contains water after extended contact with the hydrophobic surface. This limited interfacial hydration also contributed to a continuous conformation change in the adsorbed protein layer. The viscoelastic variation associated with interfacial conformation changes induces about 1.5 times overestimation of the mass uptake in the QCM-D measurements. The merit of combined multitechnique measurements is demonstrated.
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Affiliation(s)
- Cheng Zhou
- Biosensors group, Interuniversity Microelectronics Center (IMEC), Kapeldreef 75, 3001 Leuven, Belgium.
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Kandori K, Miyagawa K, Ishikawa T. Adsorption of immunogamma globulin onto various synthetic calcium hydroxyapatite particles. J Colloid Interface Sci 2004; 273:406-13. [PMID: 15082375 DOI: 10.1016/j.jcis.2004.01.069] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2003] [Accepted: 01/29/2004] [Indexed: 10/26/2022]
Abstract
This paper presents data on adsorption of immunogamma globulin (IgG) onto synthetic rodlike calcium hydroxyapatite particles (CaHaps) with various particle lengths and calcium/phosphate (Ca/P) atomic ratios ranging from 1.54 to 1.65 and compares the obtained results to those of acidic (bovine serum albumin, BSA), neutral (myoglobin, MGB), and basic (lysozyme, LSZ) proteins reported before. The effect of electrolyte concentration on IgG adsorption was also examined. The initial rate of IgG adsorption was similar to that of BSA and was slower than that of MGB and LSZ. This fact was interpreted by the difference in the structural stability and molecular weight of these proteins. The isotherms of IgG adsorption onto the CaHap particles were of pseudo-Langmuir type. The saturated amount of adsorbed IgG values (nsIgG) for the particles with mean particle length less than 70 nm decreased with increasing Ca/P ratio. The adsorption behavior of IgG molecules was very similar to that of basic LSZ, though IgG has zero net charge. The nsIgG value was increased with increased mean particle length of CaHaps; the relationship was less significant than that for BSA but similar to those for MGB and LSZ. The similar adsorption behavior of IgG and LSZ suggested that the Fab parts of IgG molecules preferentially adsorb onto CaHap to provide the reversed Y-shaped conformation of IgG. The change of the adsorption mode of IgG molecules from the reversed Y-shaped conformation to side-on by "spreading" the Fc part of IgG molecules onto the particle surface over a longer adsorption time was suggested. The nsIgG value was increased with increasing electrolyte concentration by screening the intra- and intermolecular electrostatic interactions of proteins.
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Affiliation(s)
- Kazuhiko Kandori
- School of Chemistry, Osaka University of Education, Asahigaoka 4-698-1, Kashiwara, Osaka 582-8582, Japan.
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Kamyshny A, Trofimova D, Magdassi S, Levashov A. Native and modified glucose oxidase in reversed micelles. Colloids Surf B Biointerfaces 2002. [DOI: 10.1016/s0927-7765(01)00238-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Adsorption of Native and Hydrophobically Modified Human Immunoglobulin G on Polyethylene Solid Films: Specific Recognition of Adsorbed Layers. J Colloid Interface Sci 2001. [DOI: 10.1006/jcis.2001.7907] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Baszkin A, Boissonnade MM, Kamyshny A, Magdassi S. Native and Hydrophobically Modified Human Immunoglobulin G at the Air/Water Interface. J Colloid Interface Sci 2001; 239:1-9. [PMID: 11397041 DOI: 10.1006/jcis.2001.7521] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The adsorption of human immunoglobulin G (IgG) at the air/water interface was monitored both by the in situ radiotracer technique using [(14)C] labeled IgG and by surface tension measurements. The results reveal that adsorption of IgG from single protein systems displays bimodality due to molecular rearrangements at the interface. Above the threshold value of 1.5x10(-2) mg/ml solution concentration, adsorbed IgG molecules reoriented from the side-on to the end-on configuration. The existence of a lag time which did not appear in Gamma=f(t) curves, was observed in Pi=f(t) relationships at low protein concentrations and was due to the limits of the surface pressure technique to detect protein adsorption. The adsorption of native IgG was also carried out in the presence of a hydrophobized IgG obtained by grafting capryloyl residues to its lysine groups by reaction with N-hydroxysuccinimide ester of caprylic acid, which yielded 19 covalently bound alkyl chains to the IgG molecule (19C(8)-IgG). This modified IgG exhibited enhanced adsorption at the air/water interface, as manifested by its increased adsorption efficiency relative to the native protein. Sequential and competitive adsorption experiments from binary mixtures of native IgG and 19C(8)-IgG clearly demonstrate that the displacement of the native protein from the air/water interface strongly depended on the manner of how 19C(8)-IgG and native IgG competed with each other. When the two proteins competed simultaneously, 19C(8)-IgG predominantly occupied the available area but when native IgG was adsorbed first, for 2 h, the sequentially adsorbed 19C(8)-IgG was incapable of substantially displacing it from the interface. Copyright 2001 Academic Press.
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Affiliation(s)
- A. Baszkin
- Physico Chimie des Surfaces, UMR CNRS 8612, Université Paris Sud, 5 rue J.B. Clément, Chatenay-Malabry, 92296, France
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Relkin P, Kamyshny A, Magdassi S. Changes in Calorimetric Parameters and Solvent Accessibility of Hydrophobic Groups in Native and Chemically Modified Immunoglobulin G. J Phys Chem B 2000. [DOI: 10.1021/jp993350k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- P. Relkin
- Laboratoire de Biophysique des Materiaux Alimentaires, Département Science de l’Aliment, Ecole Nationale Supérieure des Industries Alimentaires, 1, Avenue des Olympiades, 91744 Massy, France
| | - A. Kamyshny
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel
| | - S. Magdassi
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel
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Kamyshny A, Feldman A, Baszkin A, Boissonnade MM, Rosilio V, Magdassi S. Chemically Modified Glucose Oxidase with Enhanced Hydrophobicity: Adsorption at Polystyrene, Silica, and Silica Coated by Lipid Monolayers. J Colloid Interface Sci 1999; 218:300-308. [PMID: 10489305 DOI: 10.1006/jcis.1999.6440] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Covalent modification of glucose oxidase from Aspergillus niger by the palmitic acid ester of N-hydroxysuccinimide at a molar ratio ester:protein of 56:1 results in the formation of the enzyme derivative with 11 attached palmitic chains. Surface hydrophobicity measurements by a fluorescent probe, 8-anilino-1-naphthalenesulfonate, indicate a drastic increase in the hydrophobicity index of glucose oxidase after such a modification. The modified glucose oxidase displays a much higher adsorption affinity for hydrophilic (silica) as well as for hydrophobic (silica coated by phosphatidyl choline and cholesterol monolayers and polystyrene latex beads) surfaces, and forms more compact surface layers compared to the native glucose oxidase. Such a difference results from a spontaneous formation of micelle-like aggregates (clusters) of the hydrophobized enzyme molecules (average size 500 nm), which come into contact with a surface. A possible structure of the glucose oxidase surface layers and the nature of the forces determining the adsorption of the enzyme on various adsorbents are discussed. Copyright 1999 Academic Press.
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Affiliation(s)
- A Kamyshny
- Casali Institute of Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel
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