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Wang X, Guo Q, Guo J, Wang C. Magnetic composite microspheres with a controlled mesoporous shell for highly efficient DNA extraction and fragment screening. J Mater Chem B 2024; 12:4899-4908. [PMID: 38682549 DOI: 10.1039/d4tb00104d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Rapid extraction and screening of high-purity DNA fragments is an indispensable technology in advanced molecular biology. In this article, mesoporous magnetic composite microspheres (MSP@mTiO2) with tunable pore sizes were successfully fabricated for high-purity DNA extraction and fragment screening. Owing to the strong complexation ability of Ti ions with DNA phosphate groups and the high specific surface area of mesoporous microspheres, the MSP@mTiO2 microspheres possess excellent adsorption performance, where the saturated loading capacity of MSP@mTiO2 with a specific surface area of 122 m2 g-1 is as high as 575 μg mg-1 for a salmon sperm specimen. ITC experiments demonstrated that DNA adsorption on MSP@mTiO2 microspheres is mainly driven by entropy, which gives us more potential ways to regulate the balance of adsorption and desorption. Meanwhile, the mesoporous MSP@mTiO2 microspheres exhibit a much higher extraction efficiency compared with non-porous MSP@TiO2 for whole genome DNA from Arabidopsis thaliana plants. Interestingly, DNA fragments with different lengths could be screened by simply regulating the pore size of MSP@mTiO2 or the concentration of Na3PO4 in the eluent. A small pore size and low phosphate concentration are advantageous for the extraction of short-stranded DNA fragments, and DNA fragments (≤1000 bp) can be efficiently extracted when the mesopore size of MSP@mTiO2 is lower than 7.6 nm. The extraction results from the mesoporous composite microspheres provide new promising insights into the purification and screening of DNA from complex biological samples.
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Affiliation(s)
- Xiuli Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, China.
| | - Qilin Guo
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, China.
| | - Jia Guo
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, China.
| | - Changchun Wang
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200433, China.
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2
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Schmitt S, Nuhn L, Barz M, Butt HJ, Koynov K. Shining Light on Polymeric Drug Nanocarriers with Fluorescence Correlation Spectroscopy. Macromol Rapid Commun 2022; 43:e2100892. [PMID: 35174569 DOI: 10.1002/marc.202100892] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 02/04/2022] [Indexed: 11/07/2022]
Abstract
The use of nanoparticles as carriers is an extremely promising way for administration of therapeutic agents, such as drug molecules, proteins and nucleic acids. Such nanocarriers (NCs) can increase the solubility of hydrophobic compounds, protect their cargo from the environment, and if properly functionalized, deliver it to specific target cells and tissues. Polymer-based NCs are especially promising, because they offer high degree of versatility and tunability. However, in order to get a full advantage of this therapeutic approach and develop efficient delivery systems, a careful characterization of the NCs is needed. This Feature Article highlights the fluorescence correlation spectroscopy (FCS) technique as a powerful and versatile tool for NCs characterization at all stages of the drug delivery process. In particular, FCS can monitor and quantify the size of the NCs and the drug loading efficiency after preparation, the NCs stability and possible interactions with, e.g., plasma proteins in the blood stream and the kinetic of drug release in the cytoplasm of the target cells. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Sascha Schmitt
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz, 55128, Germany
| | - Lutz Nuhn
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz, 55128, Germany
| | - Matthias Barz
- Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Hans-Jürgen Butt
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz, 55128, Germany
| | - Kaloian Koynov
- Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz, 55128, Germany
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3
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Wang Z, Chen K, Hua C, Guo X. Conformation Variation and Tunable Protein Adsorption through Combination of Poly(acrylic acid) and Antifouling Poly( N-(2-hydroxyethyl) acrylamide) Diblock on a Particle Surface. Polymers (Basel) 2020; 12:E566. [PMID: 32143509 PMCID: PMC7182850 DOI: 10.3390/polym12030566] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/18/2020] [Accepted: 02/21/2020] [Indexed: 12/16/2022] Open
Abstract
Adsorption and desorption of proteins on biomaterial surfaces play a critical role in numerous biomedical applications. Spherical diblock polymer brushes (polystyrene with photoiniferter (PSV) as the core) with different block sequence, poly(acrylic acid)-b-poly(N-(2-hydroxyethyl) acrylamide) (PSV@PAA-b-PHEAA) and poly(N-(2-hydroxyethyl) acrylamide)-b-poly(acrylic acid) (PSV@PHEAA-b-PAA) were prepared via surface-initiated photoiniferter-mediated polymerization (SI-PIMP) and confirmed by a series of characterizations including TEM, Fourier transform infrared (FTIR) and elemental analysis. Both diblock polymer brushes show typical pH-dependent properties measured by dynamic light scattering (DLS) and Zeta potential. It is interesting to find out that conformation of PSV@PAA-b-PHEAA uniquely change with pH values, which is due to cooperation of electrostatic repulsion and steric hindrance. High-resolution turbidimetric titration was applied to explore the behavior of bovine serum albumin (BSA) binding to diblock polymer brushes, and the protein adsorption could be tuned by the existence of PHEAA as well as apparent PAA density. These studies laid a theoretical foundation for design of diblock polymer brushes and a possible application in biomedical fields.
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Affiliation(s)
- Zun Wang
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Z.W.); (C.H.)
| | - Kaimin Chen
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Chen Hua
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Z.W.); (C.H.)
| | - Xuhong Guo
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; (Z.W.); (C.H.)
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4
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Wei YS, Feng K, Zong MH, Wu H. pH-responsive composite micro-capsule as an efficient intestinal-specific oral delivery system for lactoferrin. Food Hydrocoll 2019. [DOI: 10.1016/j.foodhyd.2019.04.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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5
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Levin A, Cinar S, Paulus M, Nase J, Winter R, Czeslik C. Analyzing protein-ligand and protein-interface interactions using high pressure. Biophys Chem 2019; 252:106194. [PMID: 31177023 DOI: 10.1016/j.bpc.2019.106194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 05/29/2019] [Accepted: 05/29/2019] [Indexed: 01/06/2023]
Abstract
All protein function is based on interactions with the environment. Proteins can bind molecules for their transport, their catalytic conversion, or for signal transduction. They can bind to each other, and they adsorb at interfaces, such as lipid membranes or material surfaces. An experimental characterization is needed to understand the underlying mechanisms, but also to make use of proteins in biotechnology or biomedicine. When protein interactions are studied under high pressure, volume changes are revealed that directly describe spatial contributions to these interactions. Moreover, the strength of protein interactions with ligands or interfaces can be tuned in a smooth way by pressure modulation, which can be utilized in the design of drugs and bio-responsive interfaces. In this short review, selected studies of protein-ligand and protein-interface interactions are presented that were carried out under high pressure. Furthermore, a perspective on bio-responsive interfaces is given where protein-ligand binding is applied to create functional interfacial structures.
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Affiliation(s)
- Artem Levin
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Süleyman Cinar
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Michael Paulus
- Technische Universität Dortmund, Fakultät Physik/Delta, D-44221 Dortmund, Germany
| | - Julia Nase
- Technische Universität Dortmund, Fakultät Physik/Delta, D-44221 Dortmund, Germany
| | - Roland Winter
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
| | - Claus Czeslik
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany.
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6
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Müller M, Urban B, Reis B, Yu X, Grab AL, Cavalcanti-Adam EA, Kuckling D. Switchable Release of Bone Morphogenetic Protein from Thermoresponsive Poly(NIPAM- co-DMAEMA)/Cellulose Sulfate Particle Coatings. Polymers (Basel) 2018; 10:polym10121314. [PMID: 30961239 PMCID: PMC6401728 DOI: 10.3390/polym10121314] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 11/20/2018] [Accepted: 11/22/2018] [Indexed: 11/16/2022] Open
Abstract
Thermoresponsive coatings of poly(N-isopropylacrylamide-co-DMAEMA)/cellulose sulfate (PNIPAM-DMAEMA/CS) complexes are reported eluting bone-morphogenetic-protein-2 (BMP-2) on demand relevant for implant assisted local bone healing. PNIPAM-DMAEMA/CS dispersions contained colloid particles with hydrodynamic radii RH = 170⁻288 nm at T = 25 °C shrinking to RH = 74⁻103 nm at T = 60 °C. Obviously, PNIPAM-DMAEMA/CS undergoes volume phase transition (VPT) analogously to pure PNIPAM, when critical VPT temperature (VPTT) is exceeded. Temperature dependent turbidity measurements revealed broad VPT and VPTT 47 °C for PNIPAM-DMAEMA/CS colloid dispersions at pH = 7.0. FTIR spectroscopy on thermoresponsive PNIPAM-DMAEMA/CS particle coatings at germanium model substrates under HEPES buffer indicated both wet-adhesiveness and VPT behavior based on diagnostic band intensity increases with temperature. From respective temperature courses empirical VPTT ≈ 42 °C for PNIPAM-DMAEMA/CS coatings at pH = 7.0 were found, which were comparable to VPTT found for respective dispersions. Finally, the PNIPAM-DMAEMA/CS coatings were loaded with BMP-2 and model protein papain (PAP). Time dependent FTIR spectroscopic measurements showed, that for T = 37 °C there was a relative protein release of ≈30% for PAP and ≈10% for BMP-2 after 24 h, which did not increase further. Heating to T = 42 °C for PAP and to 47 °C for BMP-2 further secondary protein release of ≈20% after 24 h was found, respectively, interesting for clinical applications. BMP-2 eluted even at 47 °C was found to be still biologically active.
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Affiliation(s)
- Martin Müller
- Leibniz-Institut für Polymerforschung Dresden e.V., Abteilung Polyelektrolyte und Dispersionen, Hohe Straße 6, 01069 Dresden, Germany.
- Technische Universität Dresden, Fachrichtung für Chemie und Lebensmittelchemie, 01062 Dresden, Germany.
| | - Birgit Urban
- Leibniz-Institut für Polymerforschung Dresden e.V., Abteilung Polyelektrolyte und Dispersionen, Hohe Straße 6, 01069 Dresden, Germany.
| | - Berthold Reis
- Leibniz-Institut für Polymerforschung Dresden e.V., Abteilung Polyelektrolyte und Dispersionen, Hohe Straße 6, 01069 Dresden, Germany.
- Technische Universität Dresden, Fachrichtung für Chemie und Lebensmittelchemie, 01062 Dresden, Germany.
| | - Xiaoqian Yu
- Universität Paderborn, Department Chemie, Organische und Makromolekulare Chemie, Warburger Str. 100, 33098 Paderborn, Germany.
| | - Anna Luise Grab
- Medizinische Klinik V, Universitätsklinikum Heidelberg, INF 350, 69120 Heidelberg, Germany.
| | - Elisabetta Ada Cavalcanti-Adam
- Institute of Physical Chemistry, Department of Biophysical Chemistry, Heidelberg University, INF 253, 69120 Heidelberg, Germany.
- Max Planck Institute for Medical Research, Department of Cellular Biophysics and Central Scientific Facility "Cell Biology", Jahnstr. 29, 69120 Heidelberg, Germany.
| | - Dirk Kuckling
- Universität Paderborn, Department Chemie, Organische und Makromolekulare Chemie, Warburger Str. 100, 33098 Paderborn, Germany.
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7
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Levin A, Czeslik C. Interaction of calmodulin with poly(acrylic acid) brushes: Effects of high pressure, pH-value and ligand binding. Colloids Surf B Biointerfaces 2018; 171:478-484. [DOI: 10.1016/j.colsurfb.2018.07.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/26/2018] [Accepted: 07/30/2018] [Indexed: 12/12/2022]
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8
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Morsbach S, Gonella G, Mailänder V, Wegner S, Wu S, Weidner T, Berger R, Koynov K, Vollmer D, Encinas N, Kuan SL, Bereau T, Kremer K, Weil T, Bonn M, Butt HJ, Landfester K. Engineering von Proteinen an Oberflächen: Von komplementärer Charakterisierung zu Materialoberflächen mit maßgeschneiderten Funktionen. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201712448] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Svenja Morsbach
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Grazia Gonella
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Volker Mailänder
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
- Abteilung für Dermatologie; Universitätsmedizin der Johannes Gutenberg-Universität Mainz; Langenbeckstraße 1 55131 Mainz Deutschland
| | - Seraphine Wegner
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Si Wu
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Tobias Weidner
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
- Abteilung für Chemie; Universität Aarhus; Langelandsgade 140 8000 Aarhus C Dänemark
| | - Rüdiger Berger
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Kaloian Koynov
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Doris Vollmer
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Noemí Encinas
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Seah Ling Kuan
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Tristan Bereau
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Kurt Kremer
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Tanja Weil
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Mischa Bonn
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Hans-Jürgen Butt
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
| | - Katharina Landfester
- Max Planck-Institut für Polymerforschung; Ackermannweg 10 55128 Mainz Deutschland
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9
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Morsbach S, Gonella G, Mailänder V, Wegner S, Wu S, Weidner T, Berger R, Koynov K, Vollmer D, Encinas N, Kuan SL, Bereau T, Kremer K, Weil T, Bonn M, Butt HJ, Landfester K. Engineering Proteins at Interfaces: From Complementary Characterization to Material Surfaces with Designed Functions. Angew Chem Int Ed Engl 2018; 57:12626-12648. [PMID: 29663610 PMCID: PMC6391961 DOI: 10.1002/anie.201712448] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 03/13/2018] [Indexed: 01/17/2023]
Abstract
Once materials come into contact with a biological fluid containing proteins, proteins are generally—whether desired or not—attracted by the material's surface and adsorb onto it. The aim of this Review is to give an overview of the most commonly used characterization methods employed to gain a better understanding of the adsorption processes on either planar or curved surfaces. We continue to illustrate the benefit of combining different methods to different surface geometries of the material. The thus obtained insight ideally paves the way for engineering functional materials that interact with proteins in a predetermined manner.
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Affiliation(s)
- Svenja Morsbach
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Grazia Gonella
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Volker Mailänder
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Department of Dermatology, University Medical Center Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131, Mainz, Germany
| | - Seraphine Wegner
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Si Wu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Tobias Weidner
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.,Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Rüdiger Berger
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Kaloian Koynov
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Doris Vollmer
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Noemí Encinas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Seah Ling Kuan
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Tristan Bereau
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Kurt Kremer
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Tanja Weil
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Hans-Jürgen Butt
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Katharina Landfester
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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10
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Li S, Sun Y, Shi QH. Fabrication of high-capacity protein ion-exchangers with polymeric ion-exchange groups grafted onto micron-sized beads by atom transfer radical polymerization. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2015.07.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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11
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He SZ, Merlitz H, Sommer JU, Wu CX. Counterion-mediated protein adsorption into polyelectrolyte brushes. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2015; 38:101. [PMID: 26385737 DOI: 10.1140/epje/i2015-15101-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Revised: 08/06/2015] [Accepted: 08/17/2015] [Indexed: 06/05/2023]
Abstract
We present molecular dynamics simulations of the interaction of fullerene-like, inhomogeneously charged proteins with polyelectrolyte brushes. A motivation of this work is the experimental observation that proteins, carrying an integral charge, may enter like-charged polymer brushes. Simulations of varying charge distributions on the protein surfaces are performed to unravel the physical mechanism of the adsorption. Our results prove that an overall neutral protein can be strongly driven into polyelectrolyte brush whenever the protein features patches of positive and negative charge. The findings reported here give further evidence that the strong adsorption of proteins is also driven by entropic forces due to counterion release, since charged patches on the surface of the proteins can act as multivalent counterions of the oppositely charged polyelectrolyte chains. A corresponding number of mobile co- and counterions is released from the brush and the vicinity of the proteins so that the entropy of the total system increases.
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Affiliation(s)
- Su-Zhen He
- School of Mechanical and Electrical Engineering, Putian University, 351100, Putian, P.R. China.
- Department of Physics and ITPA, Xiamen University, 361005, Xiamen, P.R. China.
| | - Holger Merlitz
- Department of Physics and ITPA, Xiamen University, 361005, Xiamen, P.R. China
- Leibniz-Institut für Polymerforschung Dresden, 01069, Dresden, Germany
| | - Jens-Uwe Sommer
- Leibniz-Institut für Polymerforschung Dresden, 01069, Dresden, Germany
| | - Chen-Xu Wu
- Department of Physics and ITPA, Xiamen University, 361005, Xiamen, P.R. China
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12
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Zeng S, Huang YMM, Chang CEA, Zhong W. Protein binding for detection of small changes on a nanoparticle surface. Analyst 2015; 139:1364-71. [PMID: 24482794 DOI: 10.1039/c3an02155f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protein adsorption on nanoparticles is closely associated with the physicochemical properties of particles, in particular, their surface properties. We synthesized two batches of polyacrylic acid-coated nanoparticles under almost identical conditions except for the heating duration and found differences in the head-group structure of the polyacrylic acid. The structure change was confirmed by NMR and MS. The two batches of particles had varied binding affinities to a selected group of proteins. Computational work confirmed that the head group of the polymer on the surface of a nanoparticle could directly interact with a protein, and small structural changes in the head group were sufficient to result in a significant difference in the free energy of binding. Our results demonstrate that protein adsorption is so sensitive to the surface properties of particles that it can reveal even small variations in the structure of a nanoparticle surface ligand, and should be useful for quick assessment of nanoparticle properties.
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Affiliation(s)
- Shang Zeng
- Department of Chemistry, University of California, Riverside, CA 92521, USA.
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13
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Delcroix MF, Demoustier-Champagne S, Dupont-Gillain CC. Quartz crystal microbalance study of ionic strength and pH-dependent polymer conformation and protein adsorption/desorption on PAA, PEO, and mixed PEO/PAA brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:268-277. [PMID: 24328402 DOI: 10.1021/la403891k] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The conformation of polymer chains grafted on a substrate influences protein adsorption. In a previous study, adsorption/desorption of albumin was demonstrated on mixed poly(ethylene oxide) (PEO)/poly(acrylic acid) (PAA) brushes, triggered by solutions of adequate pH and ionic strength (I). In the present work, homolayers of PEO or PAA are submitted to saline solutions with pH from 3 to 9 and I from 10(-5) to 10(-1) M, and their conformation is evaluated in real time using quartz crystal microbalance with dissipation monitoring (QCM-D). Shrinkage/swelling of PAA chains and hydration and salt condensation in the brush are evidenced. The adsorption of human serum albumin (HSA) onto such brushes is also monitored in these different saline solutions, leading to a deep understanding of the influence of polymer chain conformation, modulated by pH and I, on protein adsorption. A detailed model of the conformation of PEO/PAA mixed brushes depending on pH and I is then proposed, providing a rationale for the identification of conditions for the successive adsorption and desorption of proteins on such mixed brushes. The adsorption/desorption of albumin on PEO/PAA is demonstrated using QCM-D.
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Affiliation(s)
- M F Delcroix
- Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain , Croix du Sud 1 (L7.04.01), 1348 Louvain-la-Neuve, Belgium
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14
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Qu Z, Chen K, Gu H, Xu H. Covalent Immobilization of Proteins on 3D Poly(acrylic acid) Brushes: Mechanism Study and a More Effective and Controllable Process. Bioconjug Chem 2014; 25:370-8. [DOI: 10.1021/bc400530s] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Zhenyuan Qu
- Shanghai Engineering Research
Center of Medical Device and Technology at Med-X, School of Biomedical
Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Kaimin Chen
- Shanghai Engineering Research
Center of Medical Device and Technology at Med-X, School of Biomedical
Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Hongchen Gu
- Shanghai Engineering Research
Center of Medical Device and Technology at Med-X, School of Biomedical
Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
| | - Hong Xu
- Shanghai Engineering Research
Center of Medical Device and Technology at Med-X, School of Biomedical
Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030, China
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15
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201306831] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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16
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles. Angew Chem Int Ed Engl 2013; 53:483-7. [DOI: 10.1002/anie.201306831] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/03/2013] [Indexed: 11/06/2022]
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Delcroix MF, Huet GL, Conard T, Demoustier-Champagne S, Du Prez FE, Landoulsi J, Dupont-Gillain CC. Design of Mixed PEO/PAA Brushes with Switchable Properties Toward Protein Adsorption. Biomacromolecules 2012; 14:215-25. [DOI: 10.1021/bm301637h] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- M. F. Delcroix
- Institute of Condensed Matter
and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (L7.04.01), 1348 Louvain-la-Neuve, Belgium
| | - G. L. Huet
- Institute of Condensed Matter
and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (L7.04.01), 1348 Louvain-la-Neuve, Belgium
| | - T. Conard
- IMEC,
Kapeldreef 75, 3001 Leuven, Belgium
| | - S. Demoustier-Champagne
- Institute of Condensed Matter
and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (L7.04.01), 1348 Louvain-la-Neuve, Belgium
| | - F. E. Du Prez
- Polymer Research Group, Ghent University, Krijgslaan 281 S4-bis, 9000 Ghent,
Belgium
| | - J. Landoulsi
- Laboratoire de
Réactivité
de Surface, UMR 7197 CNRS, Université Pierre and Marie Curie - Paris VI, 4 Place Jussieu, Case 178, 75252
Paris, France
| | - C. C. Dupont-Gillain
- Institute of Condensed Matter
and Nanosciences, Université catholique de Louvain, Croix du Sud 1 (L7.04.01), 1348 Louvain-la-Neuve, Belgium
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Zheng C, Liu X, Zhu J, Zhao Y. Preparation of cationic biodegradable dextran microspheres loaded with BSA and study on the mechanism of protein loading. Drug Dev Ind Pharm 2012; 38:653-8. [DOI: 10.3109/03639045.2011.589851] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Heuck CC. Polyacrylate adsorbents for the selective adsorption of cholesterol-rich lipoproteins from plasma or blood. GERMAN MEDICAL SCIENCE : GMS E-JOURNAL 2011; 9:Doc02. [PMID: 21289994 PMCID: PMC3028661 DOI: 10.3205/000125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 01/10/2011] [Indexed: 12/02/2022]
Abstract
Polyacrylate (PAA) adsorbents selectively bind low density lipoproteins (LDL) from human plasma and blood, whereas very low density lipoproteins (VLDL) are only minimally adsorbed. The adsorption of cholesterol-rich lipoproteins to PAA adsorbents is related to the molecular weight (mw) of the polyanion ligand. Ca(++) and Mg(++) inhibit the binding of LDL to PAA adsorbents. The chemical composition of the organic hardgels of the adsorbents does not have an influence on adsorption. The selective adsorption of LDL to PAA adsorbents can be explained to result from their low negative surface charge density and the specific colloid-chemical properties of the surface-bound PAA, which do not prevent LDL from binding to charge-like domains of the ligand. By contrast, VLDL and high density lipoproteins (HDL) are repelled from the adsorbents due to their higher negative surface charge density.
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Affiliation(s)
- Claus-Chr. Heuck
- Heinrich Heine University, Institute for Laboratory Medicine, Düsseldorf, Germany,*To whom correspondence should be addressed: Claus-Chr. Heuck, Heinrich Heine University, Institute for Laboratory Medicine, Moorenstr. 5, 40225 Düsseldorf, Germany, Tel.: +49-211 811 9655, E-mail:
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Reichhart C, Czeslik C. A quantitative study of the enzymatic activity of horseradish peroxidase at a planar poly(acrylic acid) brush. Colloids Surf B Biointerfaces 2010; 75:612-6. [DOI: 10.1016/j.colsurfb.2009.10.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2009] [Revised: 10/06/2009] [Accepted: 10/09/2009] [Indexed: 10/20/2022]
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Hollmann O, Reichhart C, Czeslik C. Kinetics of Protein Adsorption at a Poly(Acrylic Acid) Brush Studied by Surface Plasmon Resonance Spectroscopy. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2008.222.1.205] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The kinetics of protein adsorption at a planar poly(acrylic acid) (PAA) brush has been studied by surface plasmon resonance spectroscopy. A PAA brush has been prepared by spin-coating a gold sensor chip with a thin poly(styrene) film. Then, the diblock copolymer poly(acrylic acid)-poly(styrene) was transferred onto the film using the Langmuir–Blodgett technique generating a PAA brush with a grafting density of about 0.1 nm-2. Hen egg white lysozyme and bovine serum albumin were used as model proteins, because they carry a positive and negative net charge at the applied pH-value of 7 and interact with the negatively charged PAA brush under electrostatic attraction and repulsion, respectively. It has been found that lysozyme is strongly interacting with a PAA brush. Initial rates of adsorption are constant over time suggesting a diffusion-controlled adsorption mechanism. In contrast, a continuously decreasing adsorption rate has been observed for BSA indicating a retarding influence of already adsorbed protein molecules on the adsorption kinetics right from the beginning. For a typical protein solution concentration of 0.1 mg mL-1, the adsorbed amount of lysozyme enters a plateau region after a few seconds only, whereas in the case of BSA adsorption is slower by a factor of 100. The observed differences in the adsorption kinetics of lysozyme and BSA are discussed in the light of recent proposed models of protein adsorption at a PAA brush.
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Lu Y, Wittemann A, Ballauff M. Supramolecular Structures Generated by Spherical Polyelectrolyte Brushes and their Application in Catalysis. Macromol Rapid Commun 2009; 30:806-15. [PMID: 21706663 DOI: 10.1002/marc.200800789] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 01/28/2009] [Indexed: 11/06/2022]
Abstract
We survey recent studies on composite particles made from spherical polyelectrolyte brushes (SPB) and catalytically active nanoparticles or enzymes. SPB consist of a solid core (diameter: ca. 100 nm) onto which long chains of anionic or cationic polyelectrolyte (PE) are densely grafted ("PE brush"). Immersed in water the PE layer affixed to the colloidal core will swell due to the enormous osmotic pressure of the confined counterions ("osmotic brush"). This confinement of the counterions can be used to generate metal nanoparticles on the surface of the SPB. Moreover, enzymes can be immobilized within the PE layer. In both cases, the resulting composite particles are stable against coagulation and can be easily handled and filtered off. The catalytic activity of both systems is largely preserved in case of the enzymes, in case of the metal nanoparticles it is even enhanced. Thus, the SPB present an excellent carrier system for applications in catalysis.
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Affiliation(s)
- Yan Lu
- Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany
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Reichhart C, Czeslik C. Native-like structure of proteins at a planar poly(acrylic acid) brush. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1047-1053. [PMID: 19099523 DOI: 10.1021/la802905s] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Applying ATR-FTIR (attenuated total reflection Fourier transform infrared) and TIRF (total internal reflection fluorescence) spectroscopy, we have studied the secondary structure and aggregation properties of different proteins which are adsorbed at a poly(acrylic acid) (PAA) brush that covers a macroscopically large, planar surface. The PAA brush has been prepared on the surface of an ATR silicon crystal or a quartz plate. The preparation includes the deposition of a thin poly(styrene) film by spin-coating and the transfer of the diblock copolymer poly(styrene)-poly(acrylic acid) onto the hydrophobic film using the Langmuir-Schafer technique. It has been found that the proteins hen egg white lysozyme, bovine serum albumin, bovine alpha-lactalbumin, and bovine insulin adsorb spontaneously at a PAA brush at neutral pD values, albeit to different degrees. The secondary structure of the proteins was estimated from a decomposition of the amide I'-band in the observed ATR-FTIR spectra. Generally, the fractions of secondary structure elements recovered in this way were almost identical to those found when the proteins are native in solution. In addition, the tendency of insulin to form amyloid fibrils has also been tested when the protein is adsorbed at a planar PAA brush. Insulin is known to form amyloid fibrils in solution at low pH values and elevated temperatures. The experiments performed in this study suggest that a PAA brush does not promote fibril formation of insulin. Rather, insulin that is adsorbed at a PAA brush seems to be excluded from fibril formation pathways even at pD = 2 and 60 degrees C, where fibril formation of insulin is triggered in solution. Overall, the results of this study demonstrate that a planar PAA brush may serve as a mild environment for immobilized proteins.
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Abstract
Abstract
In this short review an introduction to the phenomenon of protein adsorption will be given. Protein adsorption often plays the central role in a wide variety of processes occurring in medicine, biochemistry, biotechnology and daily life. The main types of interactions ruling protein adsorption are summarized in this review and the principles of a few powerful experimental techniques to characterize protein adsorbates are outlined. Taking the silica/water interface as an example, the driving forces for protein adsorption are discussed on the basis of recent experimental results. Finally, the interactions of proteins with polyelectrolyte brushes are described. These brushes combine favourable properties of other interfaces and permit a controlled immobilization of protein molecules.
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Charged nanoparticles as protein delivery systems: A feasibility study using lysozyme as model protein. Eur J Pharm Biopharm 2008; 69:31-42. [DOI: 10.1016/j.ejpb.2007.10.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2007] [Revised: 09/24/2007] [Accepted: 10/08/2007] [Indexed: 11/21/2022]
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Drogoz A, Munier S, Verrier B, David L, Domard A, Delair T. Towards Biocompatible Vaccine Delivery Systems: Interactions of Colloidal PECs Based on Polysaccharides with HIV-1 p24 Antigen. Biomacromolecules 2008; 9:583-91. [DOI: 10.1021/bm701154h] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alexandre Drogoz
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
| | - Séverine Munier
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
| | - Bernard Verrier
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
| | - Laurent David
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
| | - Alain Domard
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
| | - Thierry Delair
- Unité Mixte CNRS-BioMérieux, UMR 2714, ENS Lyon, 46 Allée d’Italie, 69364 Lyon Cedex 07, France, Institut de Biologie et Chimie des Protéines, UMR 5086 CNRS, 7 Passage du Vercors, 69967 Lyon Cedex 07, France, and Laboratoire des Matériaux Polymères et des Biomatériaux, UMR CNRS 5223 Ingénierie des Matériaux Polymères, Université de Lyon, Université Lyon 1, Domaine Scientifique de la Doua, Bât. ISTIL, 15 Bd. A. Latarjet, 69622 Villeurbanne Cedex, France
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Johansson HO, Magaldi FM, Feitosa E, Pessoa A. Protein partitioning in poly(ethylene glycol)/sodium polyacrylate aqueous two-phase systems. J Chromatogr A 2008; 1178:145-53. [DOI: 10.1016/j.chroma.2007.11.071] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2007] [Revised: 11/21/2007] [Accepted: 11/26/2007] [Indexed: 11/26/2022]
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Scamporrino E, Mineo P, Dattilo S, Vitalini D, Spina E. Uncharged Water-Soluble Metal-Bis-Porphyrins Like Molecular Tweezers for Amino Acids. Macromol Rapid Commun 2007. [DOI: 10.1002/marc.200700234] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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32
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Angelini N, Micali N, Mineo P, Scamporrino E, Villari V, Vitalini D. Uncharged water-soluble Co(II)-porphyrin: a receptor for aromatic alpha-amino acids. J Phys Chem B 2007; 109:18645-51. [PMID: 16853399 DOI: 10.1021/jp052408u] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Changes in the UV-vis spectra and induced circular dichroism (ICD) signals observed, in correspondence with the porphyrin Soret region, for aqueous solutions of achiral 5,10,15,20-tetrakis{p-[omega-methoxy poly(oxy-ethylene)]phenyl}porphyrin cobalt (II) (Co-P) and aromatic alpha-L-amino acids (Trp and Phe) give direct evidence for the coordination between the Co-P and amino acids. Considering that Co-P, besides the Co atom (one-fixation-point system), does not contain in the molecule active ligand groups and that no ICD signals have been observed in the case of Co-P/Ala, it has been concluded that hydrophobic interactions or stacking interactions between the aromatic rings of the porphyrin and those of Trp or Phe, acting as further amino acid (AA) fixation points, can strongly reduce the mobility of the chiral guest, thus permitting the generation of ICD signals. The effects of changes of both pH (in the range 2-9) and amino acid structure on the ICD phenomenon have also been investigated. In particular, the following have been observed: (i) strong ICD signals for all of the Co-P/N-acetyl amino acid aqueous solutions at pH 7, (ii) an unexpected ICD band with a bisignate form for the Co-P/Ala solution at pH 9 after long aging, and (iii) an opposite ICD signal when alpha-D-Phe and alpha-D-Trp enantiomers have been used. The data reported in this paper show how the binding mechanism between receptor and AAs changes by modulating properly the pH or the molecular structures and indicate that in these aqueous solutions the coordination Co-N is not the fundamental mechanism giving rise to the formation of the complexes and that the binding can be driven by hydrophobic interactions. These occurrences, through the analysis of the spectroscopic response (and, in particular, the form of the ICD band), can allow the recognition of AAs.
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Affiliation(s)
- Nicola Angelini
- CNR-Istituto per i Processi Chimico-Fisici, sez. Messina, Via La Farina 237, I-98123 Messina, Italy
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Culbertson MJ, Williams JTB, Cheng WWL, Stults DA, Wiebracht ER, Kasianowicz JJ, Burden DL. Numerical fluorescence correlation spectroscopy for the analysis of molecular dynamics under nonstandard conditions. Anal Chem 2007; 79:4031-9. [PMID: 17447726 DOI: 10.1021/ac062013m] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The suitability of mathematical models used to extract kinetic information from correlated data constitutes a significant issue in fluorescence correlation spectroscopy (FCS). Standard FCS equations are derived from a simple Gaussian approximation of the optical detection volume, but some investigations have suggested this traditional practice can lead to inaccurate and misleading conclusions under many experimental circumstances, particularly those encountered in one-photon confocal measurements. Furthermore, analytical models cannot be derived for all measurement scenarios. We describe a novel numerical approach to FCS that circumvents conventional analytical models, enabling meaningful analyses even under extraordinarily unusual measurement conditions. Numerical fluorescence correlation spectroscopy (NFCS) involves quantitatively matching experimental correlation curves with synthetic curves generated via diffusion simulation or direct calculation based on an experimentally determined 3D map of the detection volume. Model parameters are adjusted iteratively to minimize the residual differences between synthetic and experimental correlation curves. In order to reduce analysis time, we distribute calculations across a network of processors. As an example of this new approach, we demonstrate that synthetic autocorrelation curves correspond well with experimental data and that NFCS diffusion measurements of Rhodamine B remain constant, regardless of the distortion present in a confocal detection volume.
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Leermakers FAM, Ballauff M, Borisov OV. On the mechanism of uptake of globular proteins by polyelectrolyte brushes: a two-gradient self-consistent field analysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:3937-46. [PMID: 17315900 DOI: 10.1021/la0632777] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We present model calculations for the interaction of a protein-like inhomogeneously charged nanoscale object with a layer of densely grafted polyelectrolytes ("polyelectrolyte brush"). The motivation of this work is the recent experimental observation that proteins that carry an overall negative charge are absorbed into negatively charged polyelectrolyte brushes. Two-gradient self-consistent field (2G-SCF) calculations have been performed to unravel the physical mechanism of the uptake of protein thus effected. Our results prove that an overall neutral, protein-like object can electrostatically be attracted and therefore spontaneously driven into a polyelectrolyte brush when the object has two faces (patches, domains), one with a permanent positive charge and the other with a permanent negative charge. Using a 2G-SCF analysis, we evaluate the free energy of insertion, such that the electric dipole of the inclusion is oriented parallel to the brush surface. An electroneutral protein-like object is attracted into the brush because the polyelectrolyte brush interacts asymmetrically with the charged patches of opposite sign. At high ionic strength and low charge density on the patches, the attraction cannot compete with the repulsive excluded-volume interaction. However, for low ionic strengths and sufficiently high charge density on the patches, a gain on the order of k(B)T per charge becomes possible. Hence, the asymmetry of interaction for patches of different charges may result in a total attractive force between the protein and the brush. All results obtained herein are in excellent agreement with recent experimental data.
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Affiliation(s)
- F A M Leermakers
- Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands
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Wittemann A, Azzam T, Eisenberg A. Biocompatible polymer vesicles from biamphiphilic triblock copolymers and their interaction with bovine serum albumin. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:2224-30. [PMID: 17279718 DOI: 10.1021/la062805b] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The self-assembly of the biamphiphilic triblock copolymer poly(ethylene oxide)-b-poly(caprolactone)-b-poly(acrylic acid) into polymer vesicles is studied. The vesicles provide both biocompatibility and biodegradability. Moreover, the biamphiphilic nature of the triblock copolymer provides different surface properties in the interior and in the outer interface of the vesicles. Preparation of the aggregates by direct dissolution of the copolymer in a solution of albumin does not alter the morphology of the aggregates, and thus, they have the potential to immobilize protein molecules. Since a part of the protein is encapsulated in the interior of the vesicles, they can be used as nanocontainers. A further fraction of the protein is bound to the outer interface, which is primarily composed of the poly(acrylic acid) tails. Immobilization of protein on the outer interface can stabilize the colloidal particles and also provide them with a biofunctional component.
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Affiliation(s)
- Alexander Wittemann
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6.
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36
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Hollmann O, Gutberlet T, Czeslik C. Structure and protein binding capacity of a planar PAA brush. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:1347-53. [PMID: 17241057 DOI: 10.1021/la061881b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We performed neutron reflectometry (NR) and total internal reflection fluorescence (TIRF) spectroscopy to characterize the structure and the protein binding capacity of a planar poly(acrylic acid) (PAA) brush at different temperatures. A PAA brush was prepared by spin-coating planar quartz or silicon wafers with a thin film of poly(styrene). Then, the diblock copolymer poly(styrene)-poly(acrylic acid) was deposited on these modified wafers using the Langmuir-Schäfer or Langmuir-Blodgett technique. PAA grafting densities of about 0.1 chains per nm2 were obtained. The NR experiments indicate a remarkable swelling of the PAA brush in contact with a buffer solution, when it is heated to 40 degrees C for several hours. The swollen brush structure remains upon cooling back to 20 degrees C suggesting a disentanglement of the initially formed PAA brush by the temporary heating. At pD = 6.7, the protein bovine serum albumin (BSA) with a negative net charge is strongly adsorbed to the swollen PAA brush. From the scattering length density profiles obtained from the NR curves, an almost homogeneous filling of the whole PAA brush space with BSA molecules can be deduced corresponding to an average BSA volume fraction of about 7-10% and an adsorbed protein mass of about 1.4 mg m-2. By analyzing the TIRF experiments, it is found that BSA adsorption is enhanced when increasing the temperature which represents an evidence for an entropic driving force for protein adsorption. However, the mechanism of BSA adsorption at a PAA brush appears to be different at 20 and 40 degrees C.
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Affiliation(s)
- Oliver Hollmann
- Universität Dortmund, Fachbereich Chemie, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany
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Uhlmann P, Houbenov N, Brenner N, Grundke K, Burkert S, Stamm M. In-situ investigation of the adsorption of globular model proteins on stimuli-responsive binary polyelectrolyte brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:57-64. [PMID: 17190485 DOI: 10.1021/la061557g] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Binary brushes constituted from two incompatible polymers can be used in the form of ultrathin polymeric layers as a versatile tool for surface engineering to tune physicochemical surface characteristics such as wettability, surface charge, chemical composition, and morphology and furthermore to create responsive surface properties. Mixed brushes of oppositely charged weak polyelectrolytes represent a special case of responding surfaces that are sensitive to changes in the pH value of the aqueous environment and therefore represent interesting tools for biosurface engineering. The polyelectrolyte brushes used for this study were composed of two oppositely charged polyelelctrolytes poly(2-vinylpyridine) (P2VP) and poly(acrylic acid) (PAA). The in-situ properties and surface characteristics such as as surface charge, surface tension, and extent of swelling of these brush layers are functions of the pH value of the surrounding aqueous solution. To test the behavior of the mixed polylelctrolyte brushes in contact with biosystems, protein adsorption experiments with globular model proteins were performed at different pH values and salt concentrations (confinement of counterions) of the buffer solutions. The influence of the pH value, buffer salt concentration, and isoelectric points (IEP) of the brush and protein on the adsorbed amount and the interfacial tension during protein adsorption as well as the protein adsorption mechanism postulated in reference to recently developed theories of protein adsorption on polyelectrolyte brushes is discussed. In the salted regime, protein adsorption was found to be similar to the often-described adsorption at hydrophobic surfaces. However, in the osmotic regime the balance of electrostatic repulsion and a strong entropic driving force, "counterion release", was found to be the main influence on protein adsorption.
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Affiliation(s)
- Petra Uhlmann
- Leibniz Institute of Polymer Research Dresden, Dresden, Germany.
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38
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Burkert S, Schmidt T, Gohs U, Mönch I, Arndt KF. Patterning of thin poly(N-vinyl pyrrolidone) films on silicon substrates by electron beam lithography. J Appl Polym Sci 2007. [DOI: 10.1002/app.26592] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Fletcher KA, Fakayode SO, Lowry M, Tucker SA, Neal SL, Kimaru IW, McCarroll ME, Patonay G, Oldham PB, Rusin O, Strongin RM, Warner IM. Molecular fluorescence, phosphorescence, and chemiluminescence spectrometry. Anal Chem 2006; 78:4047-68. [PMID: 16771540 PMCID: PMC2662353 DOI: 10.1021/ac060683m] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Hollmann O, Czeslik C. Characterization of a planar poly(acrylic acid) brush as a materials coating for controlled protein immobilization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:3300-5. [PMID: 16548592 DOI: 10.1021/la053110y] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The adsorption of two different proteins at a planar poly(acrylic acid) (PAA) brush was studied as a function of the ionic strength of the protein solutions applying total internal reflection fluorescence (TIRF) spectroscopy. Planar PAA brushes were prepared with a grafting density of 0.11 nm(-2) and were characterized using X-ray reflectometry. Hen egg-white lysozyme and bovine serum albumin (BSA) were used as model proteins, which have a net positive and negative charge at neutral pH-values, respectively. It has been found that both proteins adsorb strongly at a planar PAA brush at low ionic strength. Whereas lysozyme interacts with a PAA brush under electrostatic attraction at neutral pH-values, BSA binds under electrostatic repulsion at pH > 5. Even at pH = 8, significant amounts of BSA are adsorbed to a planar PAA brush. In addition, the reversibility of BSA adsorption has been characterized. Dilution of a BSA solution leads to an almost complete desorption of BSA from a PAA brush at short contact times. When the ionic strength of the protein solutions is increased to about 100-200 mM, a planar PAA brush appears largely protein-resistant, regardless of the protein net charge. The results of this study indicate that the salt-dependent protein affinity of a PAA brush represents a unique effect that must be explained by a novel protein-binding mechanism. On the basis of a recent model, it is suggested that a release of counterions is the most probable driving force for protein adsorption at a PAA brush. In a general view, this study characterizes a planar PAA brush as a new materials coating for the controlled immobilization of proteins whose use in biotechnological applications appears to be rewarding.
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Affiliation(s)
- Oliver Hollmann
- Universität Dortmund, Fachbereich Chemie, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany
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Cooper C, Dubin P, Kayitmazer A, Turksen S. Polyelectrolyte–protein complexes. Curr Opin Colloid Interface Sci 2005. [DOI: 10.1016/j.cocis.2005.05.007] [Citation(s) in RCA: 552] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Jackler G, Czeslik C, Steitz R, Royer CA. Spatial distribution of protein molecules adsorbed at a polyelectrolyte multilayer. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:041912. [PMID: 15903706 DOI: 10.1103/physreve.71.041912] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Indexed: 05/02/2023]
Abstract
The spatial distribution of protein molecules interacting with a planar polyelectrolyte multilayer was determined using neutron reflectometry. Staphylococcal nuclease (SNase) was used as model protein that was adsorbed to the multilayer at 22 degrees C and 42 degrees C. At each temperature, the protein solution was adjusted to pD -values of 4.9 and 7.5 to vary the net charge of the protein molecules. The multilayer was built up on a silicon wafer by the deposition of poly(ethylene imine) (PEI), poly(styrene sulfonate) (PSS), and poly(allylamine hydrochloride) (PAH) in the order Si-PEI-PSS- (PAH-PSS)(5). Applying the contrast variation technique, two different neutron reflectivity curves were measured at each condition of temperature and pD -value. From the analysis of the curves, protein density profiles normal to the interface were recovered. Remarkably, it has been found that SNase is partially penetrating into the polyelectrolyte multilayer after adsorption at all conditions studied. The measured neutron reflectivities are consistent with a penetration depth of 50 A at pD=4.9 and 25 A at pD=7.5. Since SNase has an isoelectric point of pH=9.5, it carries a net positive charge at both pD -values and interacts with the PSS final layer under electrostatic attraction conditions. However, when increasing the temperature, the amount of adsorbed protein is increasing at both pD -values indicating the dominance of entropic driving forces for the protein adsorption. Interestingly, at pD=4.9 where the protein charge is relatively high, this temperature-induced mass increase of immobilized protein is more pronounced within the polyelectrolyte multilayer, whereas at pD=7.5, closer to the isoelectric point of SNase, raising the temperature has mainly the effect to accumulate protein molecules outside the polyelectrolyte multilayer at the water interface. It is suggested that the penetration of SNase into the polyelectrolyte multilayer is related to a complexation mechanism. The complexation is essentially entropic in nature due to the release of counterions.
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Affiliation(s)
- Guido Jackler
- Universität Dortmund, Physikalische Chemie I, D-44221 Dortmund, Germany
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Anikin K, Röcker C, Wittemann A, Wiedenmann J, Ballauff M, Nienhaus GU. Polyelectrolyte-Mediated Protein Adsorption: Fluorescent Protein Binding to Individual Polyelectrolyte Nanospheres. J Phys Chem B 2005; 109:5418-20. [PMID: 16851574 DOI: 10.1021/jp0506282] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have used confocal fluorescence microscopy with single molecule sensitivity to characterize uptake and release of fluorescent protein (mEosFP) molecules by individual spherical polyelectrolyte brush (SPB) nanoparticles that were immobilized on a glass surface. The SPB particles consisted of a solid core particle of 100 nm diameter onto which long polyelectrolyte chains were affixed. They could be loaded with up to 30 000 mEosFP molecules in a solvent of low ionic strength. The concentration dependence of protein loading can be described with a simple bimolecular binding model, characterized by an equilibrium dissociation coefficient of 0.5 microM. Essentially complete release of the bound proteins was observed after increasing the ionic strength by adding 250 mM NaCl to the solvent. Fluorescence emission spectra and time-resolved fluorescence intensity decays were measured on individual, mEosFP-loaded SPB nanoparticles, and also on the dissolved mEosFP before and after adsorption. These results indicate that the mEosFP molecules remained structurally intact in this procedure. Hence, the present investigation demonstrates unambiguously that polyelectrolyte-mediated protein adsorption onto SPB particles presents a viable process for protein immobilization.
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Affiliation(s)
- Kirill Anikin
- Department of Biophysics, University of Ulm, 89069 Ulm, Germany
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Angelini N, Micali N, Villari V, Mineo P, Vitalini D, Scamporrino E. Interactions between water soluble porphyrin-based star polymer and amino acids: spectroscopic evidence of molecular binding. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:021915. [PMID: 15783360 DOI: 10.1103/physreve.71.021915] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2004] [Indexed: 05/24/2023]
Abstract
Molecular interactions giving rise to stable complexes between an uncharged water soluble cobalt-porphyrin and amino acids are investigated by time-resolved fluorescence, uv-vis, and circular dichroism measurements. This metalloporphyrin seems to act, by means of the coordination site of the cobalt of the core, as a recognition host, preferentially, with amino acids possessing aromatic groups. The binding with aliphatic amino acids requires longer time scales to be efficient and likely involves a slow kinetic process. The experimental findings suggest that, besides the metal(host)-N(guest) coordination bond, which is the common requisite for all amino acids, a preferential interaction with aromatic groups exists there. The solubility in water of the molecule, guaranteed by the polyethylene glycol arms as peripheral substituents, in the absence of electric charges, allows for a more selective discrimination of the binding process with respect to other water-soluble charged porphyrins. The interest devoted to the porphyrin-based star polymer and its recognition properties is, therefore, founded on the potential use either in polymeric matrices for material science or in aqueous solution for bioscience.
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Affiliation(s)
- Nicola Angelini
- CNR--Istituto per i Processi Chimico-Fisici, sez. Messina, Via La Farina 237, I-98123 Messina, Italy
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Wittemann A, Ballauff M. Temperature-Induced Unfolding of Ribonuclease A Embedded in Spherical Polyelectrolyte Brushes. Macromol Biosci 2005; 5:13-20. [PMID: 15633159 DOI: 10.1002/mabi.200400133] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We use Fourier Transform infrared spectroscopy (FT-IR) spectroscopy to study the thermal unfolding and refolding behavior of ribonuclease (RNase A) adsorbed to spherical polyelectrolyte brushes (SPB). The SPB consist of a solid poly(styrene) core of ca. 100 nm diameter onto which long chains of poly(styrene sulfonic acid), PSS have been densely attached. The particles bearing the adsorbed protein are dispersed in aqueous buffer solution at a pH close to the isoelectric point (9.6) of the protein. The secondary structure of the protein was analyzed by FT-IR spectroscopy and compared to the structure of the native protein before adsorption. The unfolding of the free RNase A in solution was found to be fully reversible with an unfolding temperature of 65 degrees C, in accordance to previous studies. However, after adsorption to the SPB, the unfolding temperature of the protein molecule is lowered by 10 degrees C and the Van't Hoff enthalpy of the unfolding process is significantly reduced. Moreover the unfolding of the adsorbed protein is irreversible. The phenomenon may be explained by an increase in binding sites due to unfolding of the globular structure. Protein adsorption to a spherical polyelectrolyte brush.
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Affiliation(s)
- Alexander Wittemann
- Physikalische Chemie I, Universität Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany.
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Rosenfeldt S, Wittemann A, Ballauff M, Breininger E, Bolze J, Dingenouts N. Interaction of proteins with spherical polyelectrolyte brushes in solution as studied by small-angle x-ray scattering. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2004; 70:061403. [PMID: 15697358 DOI: 10.1103/physreve.70.061403] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2004] [Indexed: 05/24/2023]
Abstract
We use small-angle x-ray scattering (SAXS) as a tool to study the binding of proteins to spherical polyelectrolyte brushes (SPB) in situ. The SPB consists of a solid core of approximately 100 nm diam onto which long polyelectrolyte chains [poly(styrene sulfonic acid, PSS) and poly(acrylic acid, PAA)] have been densely grafted. The proteins used in this investigation, Bovine Serum Albumine (BSA) and Bovine Pancreatic Ribonuclease A (RNase A), adsorb strongly to these SPB if the ionic strength is low despite their negative charge. Virtually no adsorption takes place at high ionic strength. SAXS demonstrates that both proteins are distributed within the brush. The findings reported here give further evidence that the strong adsorption of proteins to SPB is due to the "counterions release forces": The patches of positive charge on the surface of the proteins become multivalent counterions of the polyelectrolyte chains. Thus, a concomitant number of co- and counterions is thereby released and the entropy of the entire system is increased. The repulsive Coulombic interaction as well as the steric repulsion between the proteins and the brush layer are counterbalanced by this effect. The data discussed here demonstrate that the adsorption of proteins in SPB presents a new principle for the immobilization of proteins.
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Affiliation(s)
- S Rosenfeldt
- Physikalische Chemie I, University of Bayreuth, 95440 Bayreuth, Germany
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50
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Czeslik C, Jackler G, Steitz R, von Grünberg HH. Protein Binding to Like-Charged Polyelectrolyte Brushes by Counterion Evaporation. J Phys Chem B 2004. [DOI: 10.1021/jp0488766] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Claus Czeslik
- Universität Dortmund, Physikalische Chemie I, D-44227 Dortmund, Germany
| | - Guido Jackler
- Universität Dortmund, Physikalische Chemie I, D-44227 Dortmund, Germany
| | - Roland Steitz
- Hahn-Meitner-Institut Berlin, D-14109 Berlin, Germany
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