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De France KJ, Xu F, Toufanian S, Chan KJ, Said S, Stimpson TC, González-Martínez E, Moran-Mirabal JM, Cranston ED, Hoare T. Multi-scale structuring of cell-instructive cellulose nanocrystal composite hydrogel sheets via sequential electrospinning and thermal wrinkling. Acta Biomater 2021; 128:250-261. [PMID: 33945881 DOI: 10.1016/j.actbio.2021.04.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/07/2021] [Accepted: 04/21/2021] [Indexed: 12/22/2022]
Abstract
Structured hydrogel sheets offer the potential to mimic the mechanics and morphology of native cell environments in vitro; however, controlling the morphology of such sheets across multiple length scales to give cells consistent multi-dimensional cues remains challenging. Here, we demonstrate a simple two-step process based on sequential electrospinning and thermal wrinkling to create nanocomposite poly(oligoethylene glycol methacrylate)/cellulose nanocrystal hydrogel sheets with a highly tunable multi-scale wrinkled (micro) and fibrous (nano) morphology. By varying the time of electrospinning, rotation speed of the collector, and geometry of the thermal wrinkling process, the hydrogel nanofiber density, fiber alignment, and wrinkle geometry (biaxial or uniaxial) can be independently controlled. Adhered C2C12 mouse myoblast muscle cells display a random orientation on biaxially wrinkled sheets but an extended morphology (directed preferentially along the wrinkles) on uniaxially wrinkled sheets. While the nanofiber orientation had a smaller effect on cell alignment, parallel nanofibers promoted improved cell alignment along the wrinkle direction while perpendicular nanofibers disrupted alignment. The highly tunable structures demonstrated are some of the most complex morphologies engineered into hydrogels to-date without requiring intensive micro/nanofabrication approaches and offer the potential to precisely regulate cell-substrate interactions in a "2.5D" environment (i.e. a surface with both micro- and nano-structured topographies) for in vitro cell screening or in vivo tissue regeneration. STATEMENT OF SIGNIFICANCE: While structured hydrogels can mimic the morphology of natural tissues, controlling this morphology over multiple length scales remains challenging. Furthermore, the incorporation of secondary morphologies within individual hydrogels via simple manufacturing techniques would represent a significant advancement in the field of structured biomaterials and an opportunity to study complex cell-biomaterial interactions. Herein, we leverage a two-step process based on electrospinning and thermal wrinkling to prepare structured hydrogels with microscale wrinkles and nanoscale fibers. Fiber orientation/density and wrinkle geometry can be independently controlled during the electrospinning and thermal wrinkling processes respectively, demonstrating the flexibility of this technique for creating well-defined multiscale hydrogel structures. Finally, we show that while wrinkle geometry is the major determinant of cell alignment, nanofiber orientation also plays a role in this process.
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De France KJ, Babi M, Vapaavuori J, Hoare T, Moran-Mirabal J, Cranston ED. 2.5D Hierarchical Structuring of Nanocomposite Hydrogel Films Containing Cellulose Nanocrystals. ACS APPLIED MATERIALS & INTERFACES 2019; 11:6325-6335. [PMID: 30668100 DOI: 10.1021/acsami.8b16232] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Although two-dimensional hydrogel thin films have been applied across many biomedical applications, creating higher dimensionality structured hydrogel interfaces would enable potentially improved and more biomimetic hydrogel performance in biosensing, bioseparations, tissue engineering, drug delivery, and wound healing applications. Herein, we present a new and simple approach to control the structure of hydrogel thin films in 2.5D. Hybrid suspensions containing cellulose nanocrystals (CNCs) and aldehyde- or hydrazide-functionalized poly(oligoethylene glycol methacrylate) (POEGMA) were spin-coated onto prestressed polystyrene substrates to form cross-linked hydrogel thin films. The films were then structured via thermal shrinking, with control over the direction of shrinking leading to the formation of biaxial, uniaxial, or hierarchical wrinkles. Notably, POEGMA-only hydrogel thin films (without CNCs) did not form uniform wrinkles due to partial dewetting from the substrate during shrinking. Topographical feature sizes of CNC-POEGMA films could be tuned across 2 orders of magnitude (from ∼300 nm to 20 μm) by varying the POEGMA concentration, the length of poly(ethylene glycol) side chains in the polymer, and/or the overall film thickness. Furthermore, by employing adhesive masks during the spin-coating process, structured films with gradient wrinkle sizes can be fabricated. This precise control over both wrinkle size and wrinkle topography adds a level of functionality that to date has been lacking in conventional hydrogel networks.
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Affiliation(s)
- Kevin J De France
- Department of Chemical Engineering , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4L8 , Canada
| | - Mouhanad Babi
- Department of Chemistry and Chemical Biology , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4M1 , Canada
| | - Jaana Vapaavuori
- Department of Chemistry , University of Montreal , C.P. 6128 Succursale Centre-ville , Montreal , QC H3C 3J7 , Canada
| | - Todd Hoare
- Department of Chemical Engineering , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4L8 , Canada
| | - Jose Moran-Mirabal
- Department of Chemistry and Chemical Biology , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4M1 , Canada
| | - Emily D Cranston
- Department of Chemical Engineering , McMaster University , 1280 Main Street West , Hamilton , ON L8S 4L8 , Canada
- Department of Wood Science , University of British Columbia , 2424 Main Mall , Vancouver , BC V6T 1Z4 , Canada
- Department of Chemical and Biological Engineering , University of British Columbia , 2360 East Mall , Vancouver , BC V6T 1Z3 , Canada
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Panja A, Das S, Chakraborty A, Chakraborty P, Pal S, Nandi AK. Injectable Hydrogel of Vitamin B 9 for the Controlled Release of Both Hydrophilic and Hydrophobic Anticancer Drugs. ChemMedChem 2018; 13:2427-2436. [PMID: 30222248 DOI: 10.1002/cmdc.201800562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Indexed: 11/05/2022]
Abstract
Folic acid (FA), vitamin B9 , is a good receptor of drugs triggering cellular uptake via endocytosis. FA is sparingly soluble in water. Herein, a new approach for the formation of FA hydrogel by the hydrolysis of glucono-δ-lactone in PBS buffer under physiological conditions has been reported. The gel has a fibrillar network morphology attributable to intermolecular H-bonding and π-stacking interactions. The thixotropic property of the gel is used for the encapsulation of both hydrophilic [doxorubicin (DOX)] and hydrophobic [camptothecin (CPT)] drugs. The loading of DOX and CPT into the gel is attributed to the H-bonding interaction between FA and drugs. The release of DOX is sustainable at pH 4 and 7, and the Peppas model indicates that at pH 7 the diffusion of the drug is Fickian but it is non-Fickian at pH 4. The release of CPT is monitored by fluorescence spectroscopy, which also corroborates the combined release of both drugs. The metylthiazolyldiphenyltetrazolium bromide assay of FA hydrogel demonstrates nontoxic behavior and that the cytotoxicity of the DOX-loaded FA hydrogel is higher than that of pure DOX, with a minimal effect on normal cells.
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Affiliation(s)
- Aditi Panja
- Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Sujoy Das
- Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Atanu Chakraborty
- Centre for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Priyadarshi Chakraborty
- Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Suman Pal
- Centre for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
| | - Arun K Nandi
- Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India
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Sarkar A, Suresh KA. Self-assembly and molecular packing in cholesteryl esters at interfaces. J Chem Phys 2017; 146:214702. [PMID: 28576087 PMCID: PMC5453785 DOI: 10.1063/1.4984119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/12/2017] [Indexed: 11/14/2022] Open
Abstract
To understand the self-assembly and molecular packing in cholesteryl esters relevant to biological processes, we have studied them at the air-water and air-solid interfaces. Our phase and thickness studies employing imaging ellipsometry and atomic force microscopy along with surface manometry show that the molecular packing of cholesteryl esters at interfaces can be related to Craven's model of packing, given for bulk. At the air-water interface, following Craven's model, cholesteryl nonanoate and cholesteryl laurate exhibit a fluidic bilayer phase. Interestingly, we find the fluidic bilayer phase of cholesteryl laurate to be unstable and it switches to a crystalline bilayer phase. However, according to Craven, only cholesteryl esters with longer chain lengths starting from cholesteryl tridecanoate should show the crystalline bilayer phase. The thickness behavior of different phases was also studied by transferring the films onto a silicon substrate by using the Langmuir-Blodgett technique. Texture studies show that cholesterol, cholesteryl acetate, cholesteryl nonanoate, cholesteryl laurate, and cholesteryl myristate exhibit homogeneous films with large size domains, whereas cholesteryl palmitate and cholesteryl stearate exhibit less homogeneous films with smaller size domains. We suggest that such an assembly of molecules can be related to their molecular structures. Simulation studies may confirm such a relation.
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Affiliation(s)
- Arup Sarkar
- Centre for Nano and Soft Matter Sciences, P. B. No. 1329, Jalahalli, Bangalore 560013, India
| | - K A Suresh
- Centre for Nano and Soft Matter Sciences, P. B. No. 1329, Jalahalli, Bangalore 560013, India
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Chollet B, D'Eramo L, Martwong E, Li M, Macron J, Mai TQ, Tabeling P, Tran Y. Tailoring Patterns of Surface-Attached Multiresponsive Polymer Networks. ACS APPLIED MATERIALS & INTERFACES 2016; 8:24870-24879. [PMID: 27560306 DOI: 10.1021/acsami.6b07189] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A new strategy for the fabrication of micropatterns of surface-attached hydrogels with well-controlled chemistry is reported. The "grafting onto" approach is preferred to the "grafting from" approach. It consists of cross-linking and grafting preformed and functionalized polymer chains through thiol-ene click chemistry. The advantage is a very good control without adding initiators. A powerful consequence of thiol-ene click reaction by UV irradiation is the facile fabrication of micropatterned hydrogel thin films by photolithography. It is achieved either with photomasks using common UV lamp or without photomasks by direct drawing due to laser technology. Our versatile approach allows the fabrication of various chemical polymer networks on various solid substrates. It is demonstrated here with silicon wafers, glass and gold surfaces as substrates, and two responsive hydrogels, poly(N-isopropylacrylamide) for its responsiveness to temperature and poly(acrylic acid) for its pH-sensitivity. We also demonstrate the fabrication of stable hydrogel multilayers (or stacked layers) in which each elementary layer height can widely range from a few nanometers to several micrometers, providing an additional degree of freedom to the internal architecture of hydrogel patterns. This facile route for the synthesis of micrometer-resolute hydrogel patterns with tailored architecture and multiresponsive properties should have a strong impact.
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Affiliation(s)
- Benjamin Chollet
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
| | - Loïc D'Eramo
- Institut Pierre-Gilles de Gennes (IPGG) , 6-12 rue Jean Calvin, Paris 75005, France
| | - Ekkachai Martwong
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
| | - Mengxing Li
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
| | - Jennifer Macron
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
| | - Thuy Quyen Mai
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
| | - Patrick Tabeling
- Institut Pierre-Gilles de Gennes (IPGG) , 6-12 rue Jean Calvin, Paris 75005, France
| | - Yvette Tran
- École Supérieure de Physique et de Chimie Industrielles (ESPCI Paris), PSL Research University, Sciences et Ingénierie de la Matière Molle, CNRS UMR 7615 and Sorbonne-Universités, UPMC Univ Paris 06, SIMM , 10 rue Vauquelin, Paris F-75231 Cedex 05, France
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Kollarigowda RH, De Santo I, Rianna C, Fedele C, Manikas AC, Cavalli S, Netti PA. Shedding light on azopolymer brush dynamics by fluorescence correlation spectroscopy. SOFT MATTER 2016; 12:7102-7111. [PMID: 27491890 DOI: 10.1039/c6sm01482h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Understanding the response to illumination at a molecular level as well as characterising polymer brush dynamics are key features that guide the engineering of new light-stimuli responsive materials. Here, we report on the use of a confocal microscopy technique that was exploited to discern how a single molecular event such as the photoinduced isomerisation of azobenzene can affect an entire polymeric material at a macroscopic level leading to photodriven mass-migration. For this reason, a set of polymer brushes, containing azobenzene (Disperse Red 1, DR) on the side chains of poly(methacrylic acid), was synthesised and the influence of DR on the polymer brush dynamics was investigated for the first time by Fluorescence Correlation Spectroscopy (FCS). Briefly, two dynamics were observed, a short one coming from the isomerisation of DR and a long one related to the brush main chain. Interestingly, photoinduced polymer aggregation in the confocal volume was observed.
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Affiliation(s)
- R H Kollarigowda
- Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci 53, 80125, Naples, Italy.
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7
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Cumurcu A, Feng X, Ramos LD, Hempenius MA, Schön P, Vancso GJ. Sub-nanometer expansions of redox responsive polymer films monitored by imaging ellipsometry. NANOSCALE 2014; 6:12089-12095. [PMID: 25195609 DOI: 10.1039/c4nr02852j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We describe a novel approach to quantitatively visualize sub nm height changes occurring in thin films of redox active polymers upon reversible electrochemical oxidation/reduction in situ and in real-time with electrochemical imaging ellipsometry (EC-IE). Our approach is based on the utilization of a micro-patterned substrate containing circular patterns of passive (non-redox active) 11-mercapto-1-undecanol (MCU) within a redox-responsive oligoethylene sulfide end-functionalized poly(ferrocenyldimethylsilane) (ES-PFS) film on a gold substrate. The non-redox responsive MCU layer was used as a molecular reference layer for the direct visualization of the minute thickness variations of the ES-PFS film. The ellipsometric microscopy images were recorded in aqueous electrolyte solutions at potentials of -0.1 V and 0.6 V vs. Ag/AgCl corresponding to the reduced and oxidized redox states of ES-PFS, respectively. The ellipsometric contrast images showed a 37 (±2)% intensity increase in the ES-PFS layer upon oxidation. The thickness of the ES-PFS layer reversibly changed between 4.0 (±0.1) nm and 3.4 (±0.1) nm upon oxidation and reduction, respectively, as determined by IE. Additionally, electrochemical atomic force microscopy (EC-AFM) was used to verify the redox controlled thickness variations. The proposed method opens novel avenues to optically visualize minute and rapid height changes occurring e.g. in redox active (and other stimulus responsive) polymer films in a fast and non-invasive manner.
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Affiliation(s)
- Aysegul Cumurcu
- Department of Materials Science and Technology of Polymers, University of Twente, MESA+ Institute for Nanotechnology, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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8
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Teichmann J, Valtink M, Nitschke M, Gramm S, Funk RHW, Engelmann K, Werner C. Tissue engineering of the corneal endothelium: a review of carrier materials. J Funct Biomater 2013; 4:178-208. [PMID: 24956190 PMCID: PMC4030930 DOI: 10.3390/jfb4040178] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 09/13/2013] [Accepted: 09/24/2013] [Indexed: 12/13/2022] Open
Abstract
Functional impairment of the human corneal endothelium can lead to corneal blindness. In order to meet the high demand for transplants with an appropriate human corneal endothelial cell density as a prerequisite for corneal function, several tissue engineering techniques have been developed to generate transplantable endothelial cell sheets. These approaches range from the use of natural membranes, biological polymers and biosynthetic material compositions, to completely synthetic materials as matrices for corneal endothelial cell sheet generation. This review gives an overview about currently used materials for the generation of transplantable corneal endothelial cell sheets with a special focus on thermo-responsive polymer coatings.
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Affiliation(s)
- Juliane Teichmann
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Monika Valtink
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
| | - Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Stefan Gramm
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
| | - Richard H W Funk
- Institute of Anatomy, Medical Faculty Carl Gustav Carus, Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
| | - Katrin Engelmann
- CRTD/DFG-Center for Regenerative Therapies Dresden-Cluster of Excellence, Fetscherstraße 105, Dresden 01307, Germany.
| | - Carsten Werner
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Institute of Biofunctional Polymer Materials, Hohe Straße 6, Dresden 01069, Germany.
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9
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Kooij ES, Sui X, Hempenius MA, Zandvliet HJW, Vancso GJ. Probing the Thermal Collapse of Poly(N-isopropylacrylamide) Grafts by Quantitative in Situ Ellipsometry. J Phys Chem B 2012; 116:9261-8. [DOI: 10.1021/jp304364m] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- E. Stefan Kooij
- Physics of Interfaces and Nanomaterials,
MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Xiaofeng Sui
- Materials Science and Technology
of Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Mark A. Hempenius
- Materials Science and Technology
of Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - Harold J. W. Zandvliet
- Physics of Interfaces and Nanomaterials,
MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - G. Julius Vancso
- Materials Science and Technology
of Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
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10
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Herzog G, Abul Kashem MM, Benecke G, Buffet A, Gehrke R, Perlich J, Schwartzkopf M, Körstgens V, Meier R, Niedermeier MA, Rawolle M, Ruderer MA, Müller-Buschbaum P, Wurth W, Roth SV. Influence of nanoparticle surface functionalization on the thermal stability of colloidal polystyrene films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:8230-8237. [PMID: 22519820 DOI: 10.1021/la3007348] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The installation of large scale colloidal nanoparticle thin films is of great interest in sensor technology or data storage. Often, such devices are operated at elevated temperatures. In the present study, we investigate the effect of heat treatment on the structure of colloidal thin films of polystyrene (PS) nanoparticles in situ by using the combination of grazing incidence small-angle X-ray scattering (GISAXS) and optical ellipsometry. In addition, the samples are investigated with optical microscopy, atomic force microscopy (AFM), and field emission scanning electron microscopy (FESEM). To install large scale coatings on silicon wafers, spin-coating of colloidal pure PS nanoparticles and carboxylated PS nanoparticles is used. Our results indicate that thermal annealing in the vicinity of the glass transition temperature T(g) of pure PS leads to a rapid loss in the ordering of the nanoparticles in spin-coated films. For carboxylated particles, this loss of order is shifted to a higher temperature, which can be useful for applications at elevated temperatures. Our model assumes a softening of the boundaries between the individual colloidal spheres, leading to strong changes in the nanostructure morphology. While the nanostructure changes drastically, the macroscopic morphology remains unaffected by annealing near T(g).
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Affiliation(s)
- Gerd Herzog
- HASYLAB at DESY, Notkestr. 85, D-22607 Hamburg, Germany.
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11
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Nitschke M, Ricciardi S, Gramm S, Zschoche S, Herklotz M, Rivolo P, Werner C. Surface modification of cell culture carriers: routes to anhydride functionalization of polystyrene. Colloids Surf B Biointerfaces 2011; 90:41-7. [PMID: 22014935 DOI: 10.1016/j.colsurfb.2011.09.034] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 09/12/2011] [Accepted: 09/21/2011] [Indexed: 12/01/2022]
Abstract
Physico-chemical and topographical cues allow to control the behavior of adherent cells. Towards this goal, commercially available cell culture carriers can be finished with a laterally microstructured biomolecular functionalization. As shown in a previous study [Biomacromolecules 4 (2003) 1072], the anhydride moiety facilitates a simple and versatile way to protein binding. The present work addresses the technical issue of anhydride surface functionalization of polystyrene, the most common material for cell culture ware. Different approaches based on low pressure plasma, electron beam and ultraviolet light techniques (i.e. maleic anhydride plasma reactions; plasma, electron beam and UV immobilization of functional polymer thin films; grafting of functional polymers to plasma activated surfaces) are introduced and briefly illustrated with examples. Results are characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and ellipsometry. The different routes are compared in terms of technical feasibility and achievable surface properties.
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Affiliation(s)
- Mirko Nitschke
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Dresden, Germany.
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12
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High spatial resolution label-free detection of antigen–antibody binding on patterned surface by imaging ellipsometry. J Colloid Interface Sci 2011; 360:826-33. [DOI: 10.1016/j.jcis.2011.04.107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 04/30/2011] [Accepted: 04/30/2011] [Indexed: 01/12/2023]
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13
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Roth SV, Herzog G, Körstgens V, Buffet A, Schwartzkopf M, Perlich J, Abul Kashem MM, Döhrmann R, Gehrke R, Rothkirch A, Stassig K, Wurth W, Benecke G, Li C, Fratzl P, Rawolle M, Müller-Buschbaum P. In situ observation of cluster formation during nanoparticle solution casting on a colloidal film. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:254208. [PMID: 21654049 DOI: 10.1088/0953-8984/23/25/254208] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We present a real-time study of the nanostructuring and cluster formation of gold nanoparticles deposited in aqueous solution on top of a pre-structured polystyrene colloidal thin film. Cluster formation takes place at different length scales, from the agglomerations of the gold nanoparticles to domains of polystyrene colloids. By combining in situ imaging ellipsometry and microbeam grazing incidence small-angle x-ray scattering, we are able to identify different stages of nanocomposite formation, namely diffusion, roughness increase, layer build-up and compaction. The findings can serve as a guideline for nanocomposite tailoring by solution casting.
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Affiliation(s)
- S V Roth
- Deutsches Elektronen-Synchrotron (DESY), Notkestrabe, Hamburg, Germany.
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14
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Popa AM, Angeloni S, Bürgi T, Hubbell JA, Heinzelmann H, Pugin R. Dynamic perspective on the function of thermoresponsive nanopores from in situ AFM and ATR-IR investigations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:15356-65. [PMID: 20822117 DOI: 10.1021/la102611k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This article describes the morphological and chemical characterization of stimuli-responsive functionalized silicon surfaces provided in parallel by atomic force spectroscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) enhanced by the single-beam sample reference attenuated total reflection method (SBSR-ATR). The stimuli-responsive behavior of the surfaces was obtained by grafting-to in melt carboxyl-terminated poly-N-isopropylacryl amides (PNIPAAM) with different degree of polymerization (DP) on epoxide-functionalized silicon substrates. The unprecedented real time and in situ physicochemical insight into the temperature-triggered response of the densely packed superficial brushes allowed for the selection of a PNIPAAM with a specific DP as a suitable polymer for the fabrication of silicon membranes exhibiting switchable nanopores. The fabrication process combines the manufacture of nanoporous silicon surfaces and their subsequent chemical functionalization by the grafting-to in melt of the selected polymer. Then, relevant information was obtained in what concerns the chemical modifications behind the topographical changes that drive the functioning of PNIPAAM-based hybrid nanovalves as well as the timescale on which the opening and closing of the nanopores occur.
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Affiliation(s)
- Ana Maria Popa
- Centre Suisse d'Electronique et de Microtechnique SA, Rue Jaquet Droz 1, CH-2000 Neuchâtel, Switzerland.
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Körstgens V, Wiedersich J, Meier R, Perlich J, Roth SV, Gehrke R, Müller-Buschbaum P. Combining imaging ellipsometry and grazing incidence small angle X-ray scattering for in situ characterization of polymer nanostructures. Anal Bioanal Chem 2009; 396:139-49. [PMID: 19685043 DOI: 10.1007/s00216-009-3008-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 07/22/2009] [Accepted: 07/23/2009] [Indexed: 10/20/2022]
Abstract
A combination of microbeam grazing incidence small angle X-ray scattering (muGISAXS) and imaging ellipsometry is introduced as a new versatile tool for the characterization of nanostructures. muGISAXS provides a local lateral and depth-sensitive structural characterization, and imaging ellipsometry adds the position-sensitive determination of the three-dimensional morphology in terms of thickness, roughness, refractive index, and extinction coefficient. Together muGISAXS and imaging ellipsometry enable a complete characterization of structure and morphology. On the basis of an example of buildup of nanostructures from monodisperse colloidal polystyrene nanospheres on a rough solid support, the scope of this new combination is demonstrated. Roughness is introduced by a dewetting structure of a diblock copolymer film with one block being compatible with the colloidal nanoparticles and one block being incompatible. To demonstrate the potential for kinetic investigations, muGISAXS and imaging ellipsometry are applied to probe the drying process of an aqueous dispersion of nanospheres on such a type of rough substrate.
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Affiliation(s)
- Volker Körstgens
- Physik-Department E13, Technische Universität München, James-Franck-Str. 1, 85747, Garching, Germany
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16
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17
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18
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Lee JY, Shah SS, Yan J, Howland MC, Parikh AN, Pan T, Revzin A. Integrating sensing hydrogel microstructures into micropatterned hepatocellular cocultures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:3880-6. [PMID: 19275186 PMCID: PMC2749523 DOI: 10.1021/la803635r] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this paper we describe a microfabrication-derived approach for defining interactions between distinct groups of cells and integrating biosensors with cellular micropatterns. In this approach, photoresist lithography was employed to micropattern cell-adhesive ligand (collagen I) on silane-modified glass substrates. Poly(ethylene glycol) (PEG) photolithography was then used to fabricate hydrogel microstructures in registration with existing collagen I domains. A glass substrate modified in this manner had three types of micropatterned regions: cell-adhesive collagen I domains, moderately adhesive silanized glass regions, and nonadhesive PEG hydrogel regions. Incubation of this substrate with primary rat hepatocytes or HepG2 cells resulted in attachment of hepatic cells on collagen I domains with no adhesion observed on silane-modified glass regions or hydrogel domains. 3T3 fibroblasts added onto the same surface attached on the glass regions around the hepatocytes, completing the coculture. Significantly, PEG hydrogel microstructures remained free of cells and were used to "fence" hepatocytes from fibroblasts, thus limiting communication between the cell types. We also demonstrated that entrapment of enzyme molecules inside hydrogel microstructures did not compromise nonfouling properties of PEG. Building on this result, horse radish peroxidase-containing hydrogel microstructures were integrated into micropatterned cocultures and were used to detect hydrogen peroxide in the culture medium. The surface micropatterning approach described here may be used in the future to simultaneously define and detect endocrine signaling between two distinct cell types.
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Affiliation(s)
- Ji Youn Lee
- Department of Biomedical Engineering, Applied Science Graduate Group, University of California, Davis, California 95616, USA
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19
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Zhang N, Knoll W. Thermally Responsive Hydrogel Films Studied by Surface Plasmon Diffraction. Anal Chem 2009; 81:2611-7. [DOI: 10.1021/ac802527j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nan Zhang
- Institute of Materials Research and Engineering, A-Star (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, and Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
| | - Wolfgang Knoll
- Institute of Materials Research and Engineering, A-Star (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602, and Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
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20
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21
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Reichelt S, Gohs U, Simon F, Fleischmann S, Eichhorn KJ, Voit B. Immobilization of a hyperbranched polyester via grafting-to and electron beam irradiation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:9392-9400. [PMID: 18646782 DOI: 10.1021/la8006662] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Stable thin films of an aromatic-aliphatic hyperbranched polyester with hydroxyl groups were fabricated on silicon substrates using electron beam irradiation and a grafting-to approach. We present a detailed study on the influence of the dose, dose rate, and temperature on the film properties and degradation behavior of the polyester immobilized by electron beam irradiation. A patterned polyester film was prepared on the substrate using a masking technique. In the second part of this work, we report on a method for the strong binding of the hyperbranched polyester onto the surface of an "activated" silicon substrate without using any coupling agent. The results are compared with the grafting-to of the hydroxyl-terminated polyester using thin PGMA anchoring layers ( Reichelt et al. Macromol. Symp. 2007, 254, 240- 247 ). The optimal conditions and mechanism of the anchoring procedures were investigated. The surface and film properties of all immobilized polymer films were characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), electrokinetic measurements, contact-angle measurements by drop-shape analysis, spectroscopic and imaging ellipsometry, and infrared spectroscopy. It is shown that all immobilization methods can be optimized in such a way that the polymer surface properties remain unchanged compared to those of nongrafted polyesters.
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Affiliation(s)
- Senta Reichelt
- Leibniz Institute of Polymer Research Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany
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22
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Li X, Cui Y, Xiao J, Liao L. Hydrogel–hydrogel composites: The interfacial structure and interaction between water and polymer chains. J Appl Polym Sci 2008. [DOI: 10.1002/app.27854] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Eliseeva OV, Fokkink RG, Besseling NAM, Koopal LK, Cohen Stuart MA. Thinning of wetting films formed from aqueous solutions of non-ionic surfactant. J Colloid Interface Sci 2006; 301:210-6. [PMID: 16780864 DOI: 10.1016/j.jcis.2006.04.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2005] [Revised: 03/31/2006] [Accepted: 04/16/2006] [Indexed: 10/24/2022]
Abstract
We investigated the thinning of wetting films formed from aqueous solution of non-ionic triblock copolymer Pluronic F127 on the surface of silica using a home-made thin film balance and time-resolved ellipsometry. Imaging ellipsometry was used to visualize the film structures at subsequent stages of their development. The results unambiguously show that the time required for the formation of steady films strongly depends on the electrolyte concentration. When increasing the latter from 10(-4) to 0.1 M, this time typically increases with several orders of magnitude, from a few minutes to several hours. Moreover, for sufficiently large amounts of salt, two characteristic relaxation regimes can be clearly identified. After initial quick thinning, further thinning slows down enormously. These typical kinetic regimes are thought to result from the coupled dependencies of the bulk and interfacial properties of F127 on salt concentration. Possible explanations of the phenomenon are discussed.
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Affiliation(s)
- O V Eliseeva
- Laboratory of Physical Chemistry and Colloid Science, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
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24
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Ionov L, Stamm M, Diez S. Reversible switching of microtubule motility using thermoresponsive polymer surfaces. NANO LETTERS 2006; 6:1982-7. [PMID: 16968012 DOI: 10.1021/nl0611539] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report a novel approach for the dynamic control of gliding microtubule motility by external stimuli. Our approach is based on the fabrication of a composite surface where functional kinesin motor-molecules are adsorbed onto a silicon substrate between surface-grafted polymer chains of thermoresponsive poly(N-isopropylacrylamide). By external temperature control between 27 and 35 degrees C, we demonstrate the reversible landing, gliding, and releasing of motor-driven microtubules in response to conformational changes of the polymer chains. Our method represents a versatile means to control the activity of biomolecular motors, and other surface-coupled enzyme systems, in bionanotechnological applications.
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Affiliation(s)
- Leonid Ionov
- Max-Planck-Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
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25
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Muthukrishnan S, Nitschke M, Gramm S, Ozyürek Z, Voit B, Werner C, Müller AHE. Immobilized Hyperbranched Glycoacrylate Films as Bioactive Supports. Macromol Biosci 2006; 6:658-66. [PMID: 16881044 DOI: 10.1002/mabi.200600064] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
[Image: see text] We report on the low-pressure plasma immobilization, characterization and application of thin films of hyperbranched glycoacrylates, poly(3-O-acryloyl-alpha,beta-D-glucopyranoside) (AGlc), on PTFE-like fluorocarbon surfaces. This method is an efficient and versatile way to immobilize sugar-carrying branched acrylates as thin films of approximately 5 nm thickness on polymeric substrates while the functional groups and properties of the immobilized molecules are largely retained. The extent of poly(AGlc) degradation during plasma immobilization was investigated using FTIR-ATR spectroscopy and XPS. The thickness and topography of the immobilized films were characterized using spectroscopic ellipsometry and SFM, respectively. Studies of protein adsorption, as well as cell adhesion and proliferation on the poly(AGlc) surfaces, showed that these materials are suitable for the control of biointerfacial phenomena. Fluorescence images of fibronectin adsorbed on to the branched glycoacrylate with a mask.
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Affiliation(s)
- Sharmila Muthukrishnan
- Makromolekulare Chemie II and Bayreuther Zentrum für Kolloide und Grenzflächen, Universität Bayreuth, D-95440 Bayreuth, Germany
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26
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Paredes JI, Villar-Rodil S, Tamargo-Martínez K, Martínez-Alonso A, Tascón JMD. Real-time monitoring of polymer swelling on the nanometer scale by atomic force microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:4728-33. [PMID: 16649788 DOI: 10.1021/la052428n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The swelling of a polymer surface has been monitored in real time on the nanometer scale by atomic force microscopy (AFM). After modification by oxygen plasma treatment, poly(p-phenylene terephthalamide) (PPTA) displays a characteristic nanostructured surface morphology consisting of high-lying features alternating with topographically depressed areas. Selective swelling of the least cross-linked, depressed areas after the adsorption of ambient water or water from saturated humid atmospheres was observed by tapping mode AFM operated in the attractive interaction regime. The swollen areas could be distinguished from the nonswollen ones by local variations in the sample indentation made by the AFM tip when imaging in the tapping mode repulsive interaction regime. Monitoring the swelling of the plasma-treated polymer surface provided a means to reveal the nanometer-scale heterogeneity that this type of treatment creates on the polymer surface, which is something that would not be possible otherwise. Measurement of AFM tip-sample adhesion forces evidenced rapid water adsorption onto the oxygen plasma-treated surface, supporting the idea of water-induced swelling. This high hydrophilicity was interpreted as arising from the incorporation of polar oxygen functionalities, as demonstrated by X-ray photoelectron spectroscopy (XPS).
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Affiliation(s)
- J I Paredes
- Instituto Nacional del Carbón, CSIC, Apartado 73, 33080 Oviedo, Spain.
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27
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Schäferling M, Nagl S. Optical technologies for the read out and quality control of DNA and protein microarrays. Anal Bioanal Chem 2006; 385:500-17. [PMID: 16609845 DOI: 10.1007/s00216-006-0317-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Revised: 11/02/2005] [Accepted: 01/13/2006] [Indexed: 10/24/2022]
Abstract
Microarray formats have become an important tool for parallel (or multiplexed) monitoring of biomolecular interactions. Surface-immobilized probes like oligonucleotides, cDNA, proteins, or antibodies can be used for the screening of their complementary targets, covering different applications like gene or protein expression profiling, analysis of point mutations, or immunodiagnostics. Numerous reviews have appeared on this topic in recent years, documenting the intriguing progress of these miniaturized assay formats. Most of them highlight all aspects of microarray preparation, surface chemistry, and patterning, and try to give a systematic survey of the different kinds of applications of this new technique. This review places the emphasis on optical technologies for microarray analysis. As the fluorescent read out of microarrays is dominating the field, this topic will be the focus of the review. Basic principles of labeling and signal amplification techniques will be introduced. Recent developments in total internal reflection fluorescence, resonance energy transfer assays, and time-resolved imaging are addressed, as well as non-fluorescent imaging methods. Finally, some label-free detection modes are discussed, such as surface plasmon microscopy or ellipsometry, since these are particularly interesting for microarray development and quality control purposes.
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Affiliation(s)
- Michael Schäferling
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93040 Regensburg, Germany.
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28
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Gonuguntla M, Sharma A, Subramanian SA. Elastic Contact Induced Self-Organized Patterning of Hydrogel Films. Macromolecules 2006. [DOI: 10.1021/ma0600411] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Manoj Gonuguntla
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Ashutosh Sharma
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Subash A. Subramanian
- Department of Chemical Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
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29
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Nitschke M, König U, Lappan U, Minko S, Simon F, Zschoche S, Werner C. Low pressure plasma-based approaches to fluorocarbon polymer surface modification. J Appl Polym Sci 2006. [DOI: 10.1002/app.24717] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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