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Gonzales RR, Kumagai K, Yang Z, Yang Y, Shigemura K, Matsuyama H. Simple bio-inspired coating of ureteral stent for protein and bacterial fouling and calcium encrustation control. J Biomed Mater Res B Appl Biomater 2023. [PMID: 36941716 DOI: 10.1002/jbm.b.35250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/10/2023] [Accepted: 03/07/2023] [Indexed: 03/23/2023]
Abstract
Encrustation, caused by deposition of calcium and magnesium salts present in urine, is a common problem of indwelling urinary devices, such as ureteral stent. Encrustation was also found to be related to urinary tract infections; thus, it is necessary to prepare ureteral stents with antibacterial and antifouling surfaces to mitigate the occurrence of encrustation. In this study, commercial ureteral stent was coated with polydopamine (PDA), formed from self-polymerization of dopamine. The PDA coating was optimized in terms of dopamine concentration, pH, and coating time using response surface methodology. The chosen response parameters for optimization were calcium oxalate (CaC2 O4 ) encrustation and protein adsorption. Optimized PDA coating conditions were determined to be the following: pH 9.0, 2 mg/mL DA, and 3 days coating. The optimized PDA-coated ureteral stent exhibited outstanding resistance against CaC2 O4 encrustation, protein fouling, and bacterial adhesion due to its hydrophilic and functional coating layer. In comparison with the pristine ureteral stent, PDA coating was able to suppress approximately 97% and 87% of CaC2 O4 and protein adsorption, respectively. The PDA-coated ureteral stent was compared against those of commercially available ureteral stents and found to have superior encrustation and protein fouling mitigation performance. Finally, PDA coating was found to be highly stable for a storage period of 90 days, whether stored in wet or dry conditions.
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Affiliation(s)
- Ralph Rolly Gonzales
- Research Center for Membrane and Film Technology, Kobe University, Kobe, Hyogo, Japan
| | - Kazuo Kumagai
- Research Center for Membrane and Film Technology, Kobe University, Kobe, Hyogo, Japan
- Department of Chemical Science and Engineering, Kobe University, Kobe, Hyogo, Japan
| | - Zhe Yang
- College of Civil and Transportation Engineering, Shenzhen University, Shenzhen, China
| | - Youngmin Yang
- Department of Urology, Graduate School of Medicine, Kobe University, Kobe, Hyogo, Japan
| | - Katsumi Shigemura
- Department of Urology, Kobe University Hospital, Kobe, Hyogo, Japan
- Department of International Health, Graduate School of Health Sciences, Kobe University, Kobe, Hyogo, Japan
| | - Hideto Matsuyama
- Research Center for Membrane and Film Technology, Kobe University, Kobe, Hyogo, Japan
- Department of Chemical Science and Engineering, Kobe University, Kobe, Hyogo, Japan
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2
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Wijesundera SA, Liyanage SH, Biswas P, Reuther JF, Yan M. Trehalose-Grafted Glycopolymer: Synthesis via the Staudinger Reaction and Capture of Mycobacteria. Biomacromolecules 2023; 24:238-245. [PMID: 36524824 DOI: 10.1021/acs.biomac.2c01096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A new trehalose-grafted poly(2-hydroxyethyl methacrylate) (HEMA) glycopolymer was synthesized via the perfluorophenyl azide (PFPA)-mediated Staudinger reaction between poly(HEMA-co-HEMA-PFPA) and a diphenylphosphine-derivatized trehalose. The reaction occurred rapidly at room temperature without the use of any catalyst, giving the trehalose glycopolymers over 68% yield after 1 h. The grafting density of trehalose can be controlled by the copolymer composition in poly(HEMA-co-HEMA-PFPA), resulting in 6.1% (TP1) or 37% (TP2) at 10:1 and 1:1 HEMA/HEMA-PFPA feed ratio, respectively. The trehalose glycopolymer was covalently attached on glass slides or silicon wafers using a thin film of poly(HEMA-co-HEMA-PFPA) as the adhesion layer, achieved through the C-H insertion reaction of the photogenerated singlet perfluorophenyl nitrene. To demonstrate the ability of the trehalose glycopolymer to capture mycobacteria, arrays of the trehalose glycopolymer were fabricated and treated with Mycobacterium smegmatis. Results from the optical, fluorescence, and scanning electron microscopy showed that mycobacteria were indeed captured on the trehalose glycopolymer. The amount of mycobacteria captured increased with the percent trehalose in the trehalose glycopolymer and also with the concentration of the trehalose glycopolymer. In addition, the captured bacteria could be visualized by the naked eye under the illumination of a hand-held UV lamp.
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Affiliation(s)
- Samurdhi A Wijesundera
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| | - Sajani H Liyanage
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| | - Priyanka Biswas
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| | - James F Reuther
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States
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3
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Sun D, Xie J, Chen CJ, Liu JT. Analyzation of the binding mechanism and the isoelectric point of glycated albumin with self-assembled, aptamer-conjugated films by using surface plasmon resonance. Colloids Surf B Biointerfaces 2022; 214:112445. [PMID: 35290823 DOI: 10.1016/j.colsurfb.2022.112445] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/24/2022] [Accepted: 03/03/2022] [Indexed: 10/18/2022]
Abstract
Glycated albumin(GA), a biomarker which has great potential to replace glycated hemoglobin in the diagnosis and treatment of diabetes, is being extensively studied by scientists, especially in preventive medicine. Aptamers, as novel probes, have attracted much attention due to their high specificity, wide storage conditions, and simple preparation. However, the interaction mechanism between GA and its aptamer is still unclear, hindering the progress of diabetic aptamer sensors into clinical testing. In this study, the interaction mechanism between GA and its aptamer was evaluated for the first time using surface plasmon resonance by changing the pH value, salt concentration and temperature. The successful preparation of the sensor chip is proved by the water contact angle, Atomic Force Microscope, and the X-ray photoelectron spectroscopy. This study shows that the pH can greatly affect the formation of a complex from the interaction between the aptamer and GA. The interaction mechanism between GA aptamer and GA was caused by electrostatic force. Otherwise, this is the first time to detect protein isoelectric point (pI) using SPR. This study provides an important reference for researchers of aptamer sensors from the perspective of detection environment, and promotes the use of aptamer sensors to the clinic.
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Affiliation(s)
- Dapeng Sun
- Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China; Research Center for Materials Science and Opti-Electronic Technology, College of Materials Science and Opti-Electronic Technology, University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China
| | - Jing Xie
- Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China
| | - Ching-Jung Chen
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China; School of Opto-Electronic Technology, University of Chinese Academy of Sciences, China.
| | - Jen-Tsai Liu
- University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China; Research Center for Materials Science and Opti-Electronic Technology, College of Materials Science and Opti-Electronic Technology, University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China.
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4
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Investigation of the recognition interaction between glycated hemoglobin and its aptamer by using surface plasmon resonance. Talanta 2020; 222:121466. [PMID: 33167203 DOI: 10.1016/j.talanta.2020.121466] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/25/2020] [Accepted: 07/26/2020] [Indexed: 01/07/2023]
Abstract
Glycated hemoglobin (HbA1c) has been widely explored as an important marker for monitoring and diagnosing diabetes. Due to the advantages of high selectivity, easy preparation, and convenient preservation of aptamers, research on glycated hemoglobin detection utilizing aptasensors has received much attention in recent years. However, factors such as the pH and the salt concentration of the solution and the structure of the aptamer could influence the interactions between HbA1c and the aptamer. In this study, the factors were evaluated using surface plasmon resonance (SPR). The results show that the pH and the salt concentration can greatly affect the formation of a complex between the aptamer and HbA1c. In the stereostructure of the aptamer, loop L1 may be an important motif for recognizing glycated hemoglobin. In addition, the best condition for detecting HbA1c was at pH 6, with a high sensitivity and a low limit of detection(LOD) (1.06 × 10-3RUnM /2.55 nM). The results also demonstrated that the use of an SPR aptamer biosensor can be a sensitive technique to improve the accuracy and correctness of HbA1c measurement.
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5
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Mosconi G, Stragliotto MF, Slenk W, Valenti LE, Giacomelli CE, Strumia MC, Gomez CG. Original antifouling strategy: Polypropylene films modified with chitosan‐coated silver nanoparticles. J Appl Polym Sci 2019. [DOI: 10.1002/app.48448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Giuliana Mosconi
- Departamento de Química OrgánicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA) (5000) Córdoba Argentina
| | - María Fernanda Stragliotto
- Departamento de Química OrgánicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA) (5000) Córdoba Argentina
| | - Walter Slenk
- Departamento de Química OrgánicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
| | - Laura E. Valenti
- Departamento de FisicoquímicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación en Fisicoquímica de Córdoba (INFIQC) (5000) Córdoba Argentina
| | - Carla E. Giacomelli
- Departamento de FisicoquímicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación en Fisicoquímica de Córdoba (INFIQC) (5000) Córdoba Argentina
| | - Miriam C. Strumia
- Departamento de Química OrgánicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA) (5000) Córdoba Argentina
| | - Cesar G. Gomez
- Departamento de Química OrgánicaUniversidad Nacional de Córdoba, Facultad de Ciencias Químicas (5000) Córdoba Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Investigación y Desarrollo en Ingeniería de Procesos y Química Aplicada (IPQA) (5000) Córdoba Argentina
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6
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Sundhoro M, Park J, Wu B, Yan M. Synthesis of Polyphosphazenes by a Fast Perfluoroaryl Azide-Mediated Staudinger Reaction. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00618] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Madanodaya Sundhoro
- University of
Massachusetts Lowell, 1 University Ave., Lowell, Massachusetts 01854, United States
| | - Jaehyeung Park
- University of
Massachusetts Lowell, 1 University Ave., Lowell, Massachusetts 01854, United States
- Division of Advanced Materials Engineering, Dong-Eui University, Busan 47340, Korea
| | - Bin Wu
- University of
Massachusetts Lowell, 1 University Ave., Lowell, Massachusetts 01854, United States
| | - Mingdi Yan
- University of
Massachusetts Lowell, 1 University Ave., Lowell, Massachusetts 01854, United States
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7
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Hinderer S, Sudrow K, Schneider M, Holeiter M, Layland SL, Seifert M, Schenke-Layland K. Surface functionalization of electrospun scaffolds using recombinant human decorin attracts circulating endothelial progenitor cells. Sci Rep 2018; 8:110. [PMID: 29311692 PMCID: PMC5758628 DOI: 10.1038/s41598-017-18382-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 12/11/2017] [Indexed: 01/25/2023] Open
Abstract
Decorin (DCN) is an important small leucine-rich proteoglycan present in the extracellular matrix (ECM) of many organs and tissues. Endothelial progenitor cells (EPCs) are able to interact with the surrounding ECM and bind to molecules such as DCN. Here, we recombinantly produced full-length human DCN under good laboratory practice (GLP) conditions, and after detailed immunological characterization, we investigated its potential to attract murine and human EPCs (mEPCs and hECFCs). Electrospun polymeric scaffolds were coated with DCN or stromal cell-derived factor-1 (SDF-1α) and were then dynamically cultured with both cell types. Cell viability was assessed via imaging flow cytometry. The number of captured cells was counted and compared with the non-coated controls. To characterize cell-scaffold interactions, immunofluorescence staining and scanning electron microscopy analyses were performed. We identified that DCN reduced T cell responses and attracted innate immune cells, which are responsible for ECM remodeling. A significantly higher number of EPCs attached on DCN- and SDF-1α-coated scaffolds, when compared with the uncoated controls. Interestingly, DCN showed a higher attractant effect on hECFCs than SDF-1α. Here, we successfully demonstrated DCN as promising EPC-attracting coating, which is particularily interesting when aiming to generate off-the-shelf biomaterials with the potential of in vivo cell seeding.
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Affiliation(s)
- Svenja Hinderer
- Department of Cell and Tissue Engineering, Fraunhofer-Institute for Interfacial Engineering and Biotechnology (IGB), 70569, Stuttgart, Germany
- Department of Women´s Health, Research Institute for Women's Health, Eberhard-Karls-University Tübingen, 72076, Tübingen, Germany
| | - Katrin Sudrow
- Institute of Medical Immunology and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353, Berlin, Germany
| | - Maria Schneider
- Institute of Medical Immunology and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353, Berlin, Germany
| | - Monika Holeiter
- Department of Women´s Health, Research Institute for Women's Health, Eberhard-Karls-University Tübingen, 72076, Tübingen, Germany
| | - Shannon Lee Layland
- Department of Cell and Tissue Engineering, Fraunhofer-Institute for Interfacial Engineering and Biotechnology (IGB), 70569, Stuttgart, Germany
- Department of Women´s Health, Research Institute for Women's Health, Eberhard-Karls-University Tübingen, 72076, Tübingen, Germany
| | - Martina Seifert
- Institute of Medical Immunology and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, 13353, Berlin, Germany
| | - Katja Schenke-Layland
- Department of Cell and Tissue Engineering, Fraunhofer-Institute for Interfacial Engineering and Biotechnology (IGB), 70569, Stuttgart, Germany.
- Department of Women´s Health, Research Institute for Women's Health, Eberhard-Karls-University Tübingen, 72076, Tübingen, Germany.
- Department of Medicine/Cardiology, Cardiovascular Research Laboratories, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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8
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Sterner O, Karageorgaki C, Zürcher M, Zürcher S, Scales CW, Fadli Z, Spencer ND, Tosatti SGP. Reducing Friction in the Eye: A Comparative Study of Lubrication by Surface-Anchored Synthetic and Natural Ocular Mucin Analogues. ACS APPLIED MATERIALS & INTERFACES 2017; 9:20150-20160. [PMID: 28561563 DOI: 10.1021/acsami.6b16425] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Biomaterials used in the ocular environment should exhibit specific tribological behavior to avoid discomfort and stress-induced epithelial damage during blinking. In this study, two macromolecules that are commonly employed as ocular biomaterials, namely, poly(vinylpyrrolidone) (PVP) and hyaluronan (HA), are compared with two known model glycoproteins, namely bovine submaxillary mucin (BSM) and α1-acid glycoprotein (AGP), with regard to their nonfouling efficiency, wettability, and tribological properties when freely present in the lubricant, enabling spontaneous adsorption, and when chemisorbed under low contact pressures. Chemisorbed coatings were prepared by means of photochemically triggered nitrene insertion reactions. BSM and AGP provided boundary lubrication when spontaneously adsorbed in a hydrophobic contact with a coefficient of friction (CoF) of ∼0.03-0.04. PVP and HA were found to be excellent boundary lubricants when chemisorbed (CoF ≤ 0.01). Notably, high-molecular-weight PVP generated thick adlayers, typically around 14 nm, and was able to reduce the CoF below 0.005 when slid against a BSM-coated poly(dimethylsiloxane) pin in a tearlike fluid.
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Affiliation(s)
- Olof Sterner
- SuSoS AG , Lagerstrasse 14, CH-8006 Dübendorf, Switzerland
| | | | | | - Stefan Zürcher
- SuSoS AG , Lagerstrasse 14, CH-8006 Dübendorf, Switzerland
- Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich , Vladimir-Prelog-Weg 5, CH-8093 Zurich, Switzerland
| | - Charles W Scales
- Johnson & Johnson Vision Care Inc. , Jacksonville, Florida 32256, United States
| | - Zohra Fadli
- Johnson & Johnson Vision Care Inc. , Jacksonville, Florida 32256, United States
| | - Nicholas D Spencer
- Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich , Vladimir-Prelog-Weg 5, CH-8093 Zurich, Switzerland
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9
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Sundhoro M, Park J, Jayawardana KW, Chen X, Jayawardena HSN, Yan M. Poly(HEMA-co-HEMA-PFPA): Synthesis and preparation of stable micelles encapsulating imaging nanoparticles. J Colloid Interface Sci 2017; 500:1-8. [PMID: 28395159 DOI: 10.1016/j.jcis.2017.03.099] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/22/2017] [Accepted: 03/23/2017] [Indexed: 11/28/2022]
Abstract
We report the preparation of stable micelles from random copolymers of 2-hydroxyethyl methacrylate (HEMA) and perfluorophenyl azide (PFPA)-derivatized HEMA (HEMA-PFPA). The copolymers were synthesized by RAFT polymerization at room temperature under mild conditions without affecting the azide functionality. Upon addition of water to the copolymer solution in DMSO, the random copolymers self-assembled into micelles even at the percentage of HEMA-PFPA as low as 4.5%. The size of the micelles can be controlled by the molecular weight and the concentration of the copolymer, and the percentage of HEMA-PFPA in the copolymer. In addition, iron oxide nanoparticles and quantum dots were successfully encapsulated into the micelles with high encapsulation efficiency (∼80%). These nanoparticles, which were hydrophobic and formed agglomerates in water, became fully dispersed after encapsulating into the micelles. The micelles were stable and the size remained unchanged for at least 6months.
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Affiliation(s)
- Madanodaya Sundhoro
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States
| | - Jaehyeung Park
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States
| | - Kalana W Jayawardana
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States
| | - Xuan Chen
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States
| | - H Surangi N Jayawardena
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave, Lowell, MA 01854, United States; Department of Chemistry, KTH - Royal Institute of Technology, Teknikringen, 30, S-100 44 Stockholm, Sweden.
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10
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Park J, Jin T, Liu C, Li G, Yan M. Three-Dimensional Graphene-TiO 2 Nanocomposite Photocatalyst Synthesized by Covalent Attachment. ACS OMEGA 2016; 1:351-356. [PMID: 31457133 PMCID: PMC6640790 DOI: 10.1021/acsomega.6b00113] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/16/2016] [Indexed: 05/28/2023]
Abstract
We report the synthesis of a three-dimensional graphene (3DG)-TiO2 nanocomposite by covalently attaching P25 TiO2 nanoparticles onto pristine 3DG through a perfluorophenyl azide-mediated coupling reaction. The TiO2 nanoparticles were robustly attached on the 3DG surface, with minimal particle agglomeration. In photocatalytic CO2 reduction, the 3DG-TiO2 nanocomposite demonstrated excellent activity, about 11 times higher than that of the P25 TiO2 nanoparticles. The enhanced activity can be partially attributed to the highly dispersed state of the P25 TiO2 nanoparticles on the 3DG substrate. This 3DG-based system offers a new platform for fabricating photocatalytic materials with enhanced activities.
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Affiliation(s)
- Jaehyeung Park
- Department
of Chemistry, University of Massachusetts
at Lowell, Lowell, Massachusetts 01854, United States
| | - Tong Jin
- Department
of Chemistry and Materials Science Program, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - Chao Liu
- Department
of Chemistry and Materials Science Program, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - Gonghu Li
- Department
of Chemistry and Materials Science Program, University of New Hampshire, Durham, New Hampshire 03824, United States
| | - Mingdi Yan
- Department
of Chemistry, University of Massachusetts
at Lowell, Lowell, Massachusetts 01854, United States
- Department
of Chemistry, KTH - Royal Institute of Technology, S-10044 Stockholm, Sweden
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11
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Madkou S, Melnichu I, Choukourov A, Krakovsky I, Biederman H, Schönhals A. In Situ Nanocalorimetric Investigations of Plasma Assisted Deposited Poly(ethylene oxide)-like Films by Specific Heat Spectroscopy. J Phys Chem B 2016; 120:3954-62. [PMID: 27055060 DOI: 10.1021/acs.jpcb.6b01355] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In recent years, highly cross-linked plasma polymers have started to unveil their potential in numerous biomedical applications in thin-film form. However, conventional diagnostic methods often fail due to their diverse molecular dynamics conformations. Here, glassy dynamics and the melting transition of thin PEO-like plasma assisted deposited (ppPEO) films (thickness 100 nm) were in situ studied by a combination of specific heat spectroscopy, utilizing a pJ/K sensitive ac-calorimeter chip, and composition analytical techniques. Different cross-linking densities were obtained by different plasma powers during the deposition of the films. Glassy dynamics were observed for all values of the plasma power. It was found that the glassy dynamics slows down with increasing the plasma power. Moreover, the underlying relaxation time spectra broaden indicating that the molecular motions become more heterogeneous with increasing plasma power. In a second set of the experiment, the melting behavior of the ppPEO films was studied. The melting temperature of ppPEO was found to decrease with increasing plasma power. This was explained by a decrease of the order in the crystals due to formation of chemical defects during the plasma process.
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Affiliation(s)
- Sherif Madkou
- Bundesanstalt für Materialforschung und -prüfung (BAM) , Unter den Eichen 87, 12205 Berlin, Germany
| | - Iurii Melnichu
- Department of Macromolecular Physics, Faculty of Mathematics and Physics, Charles University in Prague , V Holesovickach 2, 18000 Prague 8, Czech Republic
| | - Andrei Choukourov
- Department of Macromolecular Physics, Faculty of Mathematics and Physics, Charles University in Prague , V Holesovickach 2, 18000 Prague 8, Czech Republic
| | - Ivan Krakovsky
- Department of Macromolecular Physics, Faculty of Mathematics and Physics, Charles University in Prague , V Holesovickach 2, 18000 Prague 8, Czech Republic
| | - Hynek Biederman
- Department of Macromolecular Physics, Faculty of Mathematics and Physics, Charles University in Prague , V Holesovickach 2, 18000 Prague 8, Czech Republic
| | - Andreas Schönhals
- Bundesanstalt für Materialforschung und -prüfung (BAM) , Unter den Eichen 87, 12205 Berlin, Germany
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12
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Jayawardana KW, Jayawardena HSN, Wijesundera SA, De Zoysa T, Sundhoro M, Yan M. Selective targeting of Mycobacterium smegmatis with trehalose-functionalized nanoparticles. Chem Commun (Camb) 2016; 51:12028-31. [PMID: 26121049 DOI: 10.1039/c5cc04251h] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Silica and iron oxide nanoparticles with sizes ranging from 6 to 40 nm were functionalized with trehalose. The trehalose-conjugated nanoparticles showed strong interactions with Mycobacterium smegmatis (M. smegmatis) and minimal interactions with macrophage (RAW 264.7) or A549 cells. In addition, trehalose-conjugated silica nanoparticles selectively interacted with M. smegmatis on M. smegmatis-treated A549 cells, demonstrating high potential of trehalose in developing targeted therapy for treating mycobacterial infection.
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Affiliation(s)
- Kalana W Jayawardana
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854, USA.
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13
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Hao N, Neranon K, Ramström O, Yan M. Glyconanomaterials for biosensing applications. Biosens Bioelectron 2016; 76:113-30. [PMID: 26212205 PMCID: PMC4637221 DOI: 10.1016/j.bios.2015.07.031] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 07/11/2015] [Accepted: 07/14/2015] [Indexed: 02/08/2023]
Abstract
Nanomaterials constitute a class of structures that have unique physiochemical properties and are excellent scaffolds for presenting carbohydrates, important biomolecules that mediate a wide variety of important biological events. The fabrication of carbohydrate-presenting nanomaterials, glyconanomaterials, is of high interest and utility, combining the features of nanoscale objects with biomolecular recognition. The structures can also produce strong multivalent effects, where the nanomaterial scaffold greatly enhances the relatively weak affinities of single carbohydrate ligands to the corresponding receptors, and effectively amplifies the carbohydrate-mediated interactions. Glyconanomaterials are thus an appealing platform for biosensing applications. In this review, we discuss the chemistry for conjugation of carbohydrates to nanomaterials, summarize strategies, and tabulate examples of applying glyconanomaterials in in vitro and in vivo sensing applications of proteins, microbes, and cells. The limitations and future perspectives of these emerging glyconanomaterials sensing systems are furthermore discussed.
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Affiliation(s)
- Nanjing Hao
- Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA
| | - Kitjanit Neranon
- Department of Chemistry, KTH-Royal Institute of Technology, Teknikringen 30, S-10044 Stockholm, Sweden
| | - Olof Ramström
- Department of Chemistry, KTH-Royal Institute of Technology, Teknikringen 30, S-10044 Stockholm, Sweden.
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA; Department of Chemistry, KTH-Royal Institute of Technology, Teknikringen 30, S-10044 Stockholm, Sweden.
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14
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Sundhoro M, Wang H, Boiko ST, Chen X, Jayawardena HSN, Park J, Yan M. Fabrication of carbohydrate microarrays on a poly(2-hydroxyethyl methacrylate)-based photoactive substrate. Org Biomol Chem 2016; 14:1124-30. [DOI: 10.1039/c5ob01417d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A carbohydrate microarray was fabricated on a PHEMA-based photoactive polymer. The arrays showed strong signals, and were used to probe carbohydrate-mediated interactions with lectin and bacteria.
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Affiliation(s)
| | - Hui Wang
- Department of Chemistry
- University of Massachusetts Lowell
- Lowell
- USA
| | - Scott T. Boiko
- Department of Biology
- University of Massachusetts Lowell
- Lowell
- USA
| | - Xuan Chen
- Department of Chemistry
- University of Massachusetts Lowell
- Lowell
- USA
| | | | - JaeHyeung Park
- Department of Chemistry
- University of Massachusetts Lowell
- Lowell
- USA
| | - Mingdi Yan
- Department of Chemistry
- University of Massachusetts Lowell
- Lowell
- USA
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15
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Zhou J, Jayawardana KW, Kong N, Ren Y, Hao N, Yan M, Ramström O. Trehalose-Conjugated, Photofunctionalized Mesoporous Silica Nanoparticles for Efficient Delivery of Isoniazid into Mycobacteria. ACS Biomater Sci Eng 2015; 1:1250-1255. [DOI: 10.1021/acsbiomaterials.5b00274] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juan Zhou
- Department
of Chemistry, KTH−Royal Institute of Technology, Teknikringen
30, S-10044 Stockholm, Sweden
| | - Kalana W. Jayawardana
- Department
of Chemistry, University of Massachusetts Lowell, 1 University
Avenue, Lowell, Massachusetts 01854, United States
| | - Na Kong
- Department
of Chemistry, KTH−Royal Institute of Technology, Teknikringen
30, S-10044 Stockholm, Sweden
| | - Yansong Ren
- Department
of Chemistry, KTH−Royal Institute of Technology, Teknikringen
30, S-10044 Stockholm, Sweden
| | - Nanjing Hao
- Department
of Chemistry, University of Massachusetts Lowell, 1 University
Avenue, Lowell, Massachusetts 01854, United States
| | - Mingdi Yan
- Department
of Chemistry, KTH−Royal Institute of Technology, Teknikringen
30, S-10044 Stockholm, Sweden
- Department
of Chemistry, University of Massachusetts Lowell, 1 University
Avenue, Lowell, Massachusetts 01854, United States
| | - Olof Ramström
- Department
of Chemistry, KTH−Royal Institute of Technology, Teknikringen
30, S-10044 Stockholm, Sweden
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16
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Zhao D, Yu S, Liu G, Yuan Q, Guo H. Polypiperazine-amide nanofiltration membrane incorporated with poly(ethylene glycol) derivative for electrodialysis concentrate treatment. Sep Purif Technol 2015. [DOI: 10.1016/j.seppur.2015.08.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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17
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Uppalapati S, Kong N, Norberg O, Ramström O, Yan M. Ionization of covalent immobilized poly(4-vinylphenol) monolayers measured by ellipsometry, QCM and SPR. APPLIED SURFACE SCIENCE 2015; 343:166-171. [PMID: 26097271 PMCID: PMC4469237 DOI: 10.1016/j.apsusc.2015.03.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Covalently immobilized poly(4-vinylphenol) (PVP) monolayer films were fabricated by spin coating PVP on perfluorophenyl azide (PFPA)-functionalized surface followed by UV irradiation. The pH-responsive behavior of these PVP ultrathin films was evaluated by ellipsometry, quartz crystal microbalance (QCM) and surface plasmon resonance (SPR). By monitoring the responses of these films to pH in situ, the ionization constant of the monolayer thin films was obtained. The apparent pKa value of these covalently immobilized PVP monolayers, 13.4 by SPR, was 3 units higher than that of the free polymer in aqueous solution.
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Affiliation(s)
- Suji Uppalapati
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854, United States
| | - Na Kong
- KTH-Royal Institute of Technology, Department of Chemistry, Teknikringen 30, S-10044 Stockholm, Sweden
| | - Oscar Norberg
- KTH-Royal Institute of Technology, Department of Chemistry, Teknikringen 30, S-10044 Stockholm, Sweden
| | - Olof Ramström
- KTH-Royal Institute of Technology, Department of Chemistry, Teknikringen 30, S-10044 Stockholm, Sweden
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854, United States
- KTH-Royal Institute of Technology, Department of Chemistry, Teknikringen 30, S-10044 Stockholm, Sweden
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18
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Zorn G, Castner DG, Tyagi A, Wang X, Wang H, Yan M. Analysis of the surface density and reactivity of perfluorophenylazide and the impact on ligand immobilization. JOURNAL OF VACUUM SCIENCE & TECHNOLOGY. A, VACUUM, SURFACES, AND FILMS : AN OFFICIAL JOURNAL OF THE AMERICAN VACUUM SOCIETY 2015; 33:021407. [PMID: 25759511 PMCID: PMC4327916 DOI: 10.1116/1.4907924] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 01/29/2015] [Accepted: 01/30/2015] [Indexed: 06/04/2023]
Abstract
Perfluorophenylazide (PFPA) chemistry is a novel method for tailoring the surface properties of solid surfaces and nanoparticles. It is general and versatile, and has proven to be an efficient way to immobilize graphene, proteins, carbohydrates, and synthetic polymers. The main thrust of this work is to provide a detailed investigation on the chemical composition and surface density of the PFPA tailored surface. Specifically, gold surfaces were treated with PFPA-derivatized (11-mercaptoundecyl)tetra(ethylene glycol) (PFPA-MUTEG) mixed with 2-[2-(2-mercaptoethoxy)ethoxy]ethanol (MDEG) at varying solution mole ratios. Complementary analytical techniques were employed to characterize the resulting films including Fourier transform infrared spectroscopy to detect fingerprints of the PFPA group, x-ray photoelectron spectroscopy and ellipsometry to study the homogeneity and uniformity of the films, and near edge x-ray absorption fine structures to study the electronic and chemical structure of the PFPA groups. Results from these studies show that the films prepared from 90:10 and 80:20 PFPA-MUTEG/MDEG mixed solutions exhibited the highest surface density of PFPA and the most homogeneous coverage on the surface. A functional assay using surface plasmon resonance with carbohydrates covalently immobilized onto the PFPA-modified surfaces showed the highest binding affinity for lectin on the PFPA-MUTEG/MDEG film prepared from a 90:10 solution.
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Affiliation(s)
- Gilad Zorn
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington , Box 351653, Seattle, Washington 98195-1653
| | - David G Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington , Box 351653, Seattle, Washington 98195-1653
| | - Anuradha Tyagi
- Department of Chemistry, Portland State University , Portland, Oregon 97207-0751
| | - Xin Wang
- Department of Chemistry, Portland State University , Portland, Oregon 97207-0751
| | - Hui Wang
- Department of Chemistry, Portland State University , Portland, Oregon 97207-0751
| | - Mingdi Yan
- Department of Chemistry, Portland State University , Portland, Oregon 97207-0751
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19
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Sterner O, Giazzon M, Zürcher S, Tosatti S, Liley M, Spencer ND. Delineating fibronectin bioadhesive micropatterns by photochemical immobilization of polystyrene and poly(vinylpyrrolidone). ACS APPLIED MATERIALS & INTERFACES 2014; 6:18683-18692. [PMID: 25253530 DOI: 10.1021/am5042093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bioadhesive micropatterns, capable of laterally confining cells to a 2D lattice, have proven effective in simulating the in vivo tissue environment. They reveal fundamental aspects of the role of adhesion in cell mechanics, proliferation, and differentiation. Here we present an approach based on photochemistry for the fabrication of synthetic polymer micropatterns. Perfluorophenyl azide (PFPA), upon deep-UV exposure, forms a reactive nitrene capable of covalently linking to a molecule that is in close proximity. PFPA has been grafted onto a backbone of poly(allyl amine), which readily forms a self-assembled monolayer on silicon wafers or glass. A film of polystyrene was applied by spin-coating, and by laterally confining the UV exposure through a chromium-on-quartz photomask, monolayers of polymers could be immobilized in circular microdomains. Poly(vinylpyrrolidone) (PVP) was attached to the background to form a barrier to nonspecific protein adsorption and cell adhesion. Micropatterns were characterized with high-lateral-resolution time-of-flight secondary ion mass spectrometry (TOF-SIMS), which confirmed the formation of polystyrene domains within a PVP background. Fluorescence-microscopy adsorption assays with rhodamine-labeled bovine serum albumin demonstrated the nonfouling efficiency of PVP and, combined with TOF-SIMS, allowed for a comprehensive characterization of the pattern geometry. The applicability of the micropatterned platform in single-cell assays was tested by culturing two cell types, WM 239 melanoma cells and SaOs-2 osteoblasts, on micropatterned glass, either with or without backfilling of the patterns with fibronectin. It was demonstrated that the platform was efficient in confining cells to the fibronectin-backfilled micropatterns for at least 48 h. PVP is thus proposed as a viable, highly stable alternative to poly(ethylene glycol) for nonfouling applications. Due to the versatility of the nitrene-insertion reaction, the platform could be extended to other polymer pairs or proteins and the surface chemistry adapted to specific applications.
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Affiliation(s)
- Olof Sterner
- Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich , Vladimir-Prelog-Weg 5, CH-8093, Zürich, Switzerland
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20
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Hvasanov D, Nam EV, Peterson JR, Pornsaksit D, Wiedenmann J, Marquis CP, Thordarson P. One-Pot Synthesis of High Molecular Weight Synthetic Heteroprotein Dimers Driven by Charge Complementarity Electrostatic Interactions. J Org Chem 2014; 79:9594-602. [DOI: 10.1021/jo501713t] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
| | | | | | | | - Jörg Wiedenmann
- National
Oceanography Center, University of Southampton, Southampton SO14 3ZH, United Kingdom
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21
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Zorn G, Liu LH, Árnadóttir L, Wang H, Gamble LJ, Castner DG, Yan M. X-Ray Photoelectron Spectroscopy Investigation of the Nitrogen Species in Photoactive Perfluorophenylazide-Modified Surfaces. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2014; 118:376-383. [PMID: 24535931 PMCID: PMC3923990 DOI: 10.1021/jp409338y] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
X-ray Photoelectron Spectroscopy (XPS) was used to characterize the nitrogen species in perfluorophenylazide (PFPA) self-assembled monolayers. PFPA chemistry is a novel immobilization method for tailoring the surface properties of materials. It is a simple route for the efficient immobilization of graphene, proteins, carbohydrates and synthetic polymers onto a variety of surfaces. Upon light irradiation, the azido group in PFPA is converted to a highly reactive singlet nitrene species that readily undergoes CH insertion and C=C addition reactions. Here, the challenge of characterizing the PFPA modified surfaces was addressed by detailed XPS experimental analyses. The three nitrogen peaks detected in the XPS N1s spectra were assigned to amine/amide (400.5 eV) and azide (402.1 and 405.6 eV) species. The observed 2:1 ratio of the areas from the 402.1 eV to 405.6 eV peaks suggests the assignment of the peak at 402.1 eV to the two outer nitrogen atoms in the azido group and assignment of the peak at 405.6 eV to the central nitrogen atom in the azido group. The azide decomposition as the function of x-ray exposure was also determined. Finally, XPS analyses were conducted on patterned graphene to investigate the covalent bond formation between the PFPA and graphene. This study provides strong evidence for the formation of covalent bonds during the PFPA photocoupling process.
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Affiliation(s)
- Gilad Zorn
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Box 351653, Seattle, WA 98195-165
| | - Li-Hong Liu
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
| | - Líney Árnadóttir
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Box 351653, Seattle, WA 98195-165
| | - Hui Wang
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
| | - Lara J. Gamble
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Box 351653, Seattle, WA 98195-165
| | - David G. Castner
- National ESCA and Surface Analysis Center for Biomedical Problems, Departments of Bioengineering and Chemical Engineering, University of Washington, Box 351653, Seattle, WA 98195-165
| | - Mingdi Yan
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
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22
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Tauhardt L, Frant M, Pretzel D, Hartlieb M, Bücher C, Hildebrand G, Schröter B, Weber C, Kempe K, Gottschaldt M, Liefeith K, Schubert US. Amine end-functionalized poly(2-ethyl-2-oxazoline) as promising coating material for antifouling applications. J Mater Chem B 2014; 2:4883-4893. [DOI: 10.1039/c4tb00193a] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The antifouling properties against the simultaneous attack of five different bacteria and the stability of surface tethered poly(2-ethyl-2-oxazoline)s were investigated.
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Affiliation(s)
- Lutz Tauhardt
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Marion Frant
- Institute for Bioprocessing and Analytical Measurement Techniques e.V. (IBA)
- 37308 Heilbad Heiligenstadt, Germany
| | - David Pretzel
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Matthias Hartlieb
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Christian Bücher
- Institute for Bioprocessing and Analytical Measurement Techniques e.V. (IBA)
- 37308 Heilbad Heiligenstadt, Germany
| | - Gerhard Hildebrand
- Institute for Bioprocessing and Analytical Measurement Techniques e.V. (IBA)
- 37308 Heilbad Heiligenstadt, Germany
| | - Bernd Schröter
- Institute for Solid State Physics
- Friedrich Schiller University Jena
- 07743 Jena, Germany
| | - Christine Weber
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Kristian Kempe
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Michael Gottschaldt
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
| | - Klaus Liefeith
- Institute for Bioprocessing and Analytical Measurement Techniques e.V. (IBA)
- 37308 Heilbad Heiligenstadt, Germany
| | - Ulrich S. Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC)
- Friedrich Schiller University Jena
- 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM)
- Friedrich Schiller University Jena
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23
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Sterner O, Serrano Â, Mieszkin S, Zürcher S, Tosatti S, Callow ME, Callow JA, Spencer ND. Photochemically prepared, two-component polymer-concentration gradients. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:13031-13041. [PMID: 24059827 DOI: 10.1021/la402168z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A versatile, photochemical surface-modification approach using nitrene-insertion reactions has been employed to develop an ultrathin, two-component, polymer-gradient coating. Perfluorophenyl azide (PFPA) acted as the photosensitive moiety, forming a nitrene radical upon 254 nm UV exposure. Cationic poly(allyl amine) was grafted with PFPA and surface-anchored onto silicon wafers by means of electrostatic self-assembly. After spin-coating of polystyrene (PS), the substrate was illuminated from behind a moving shutter, thereby controlling the azide-to-nitrene conversion degree across the substrate, and leading to a gradually varying PS density after rinsing. Backfilling with poly(vinyl pyrrolidone) (PVP) and re-exposing to UV light formed a two-component polymer-density gradient. The composition varied linearly following exposure to a linear UV exposure profile, as determined with spectroscopic ellipsometry (ELM) and X-ray photoelectron spectroscopy (XPS). High-spatial-resolution, time-of-flight secondary ion mass spectrometry (ToF-SIMS) revealed a high degree of mixing between the two incompatible polymers on the micrometer scale. The dynamic water-contact angle (dCA) was found to depend strongly on the sample history, suggesting adaptive properties of the coating, which was further confirmed by angle-resolved XPS (ARXPS). To confirm the applicability of the system for biological investigations, gradients were exposed to zoospores of the macrofouling alga Ulva linza , and a critical PS composition of 70% was identified, above which settlement started to increase. It has been shown that a two-component polymer-density gradient can provide a high-throughput platform for determining critical surface properties of polymer blend materials.
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Affiliation(s)
- Olof Sterner
- Laboratory for Surface Science and Technology, Department of Materials, ETH Zurich , Wolfgang-Pauli-Str. 10, CH-8093 Zurich, Switzerland
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24
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Quartz crystal microbalance with dissipation (QCM-D) as tool to exploit antigen–antibody interactions in pancreatic ductal adenocarcinomadetection. Biosens Bioelectron 2013; 42:646-52. [DOI: 10.1016/j.bios.2012.10.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 09/22/2012] [Accepted: 10/03/2012] [Indexed: 01/14/2023]
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25
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Abstract
Graphene, a material made exclusively of sp(2) carbon atoms with its π electrons delocalized over the entire 2D network, is somewhat chemically inert. Covalent functionalization can enhance graphene's properties including opening its band gap, tuning conductivity, and improving solubility and stability. Covalent functionalization of pristine graphene typically requires reactive species that can form covalent adducts with the sp(2) carbon structures in graphene. In this Account, we describe graphene functionalization reactions using reactive intermediates of radicals, nitrenes, carbenes, and arynes. These reactive species covalently modify graphene through free radical addition, CH insertion, or cycloaddition reactions. Free radical additions are among the most common reaction, and these radicals can be generated from diazonium salts and benzoyl peroxide. Electron transfer from graphene to aryl diazonium ion or photoactivation of benzoyl peroxide yields aryl radicals that subsequently add to graphene to form covalent adducts. Nitrenes, electron-deficient species generated by thermal or photochemical activation of organic azides, can functionalize graphene very efficiently. Because perfluorophenyl nitrenes show enhanced bimolecular reactions compared with alkyl or phenyl nitrenes, perfluorophenyl azides are especially effective. Carbenes are used less frequently than nitrenes, but they undergo CH insertion and C═C cycloaddition reactions with graphene. In addition, arynes can serve as a dienophile in a Diels-Alder type reaction with graphene. Further study is needed to understand and exploit the chemistry of graphene. The generation of highly reactive intermediates in these reactions leads to side products that complicate the product composition and analysis. Fundamental questions remain about the reactivity and regioselectivity of graphene. The differences in the basal plane and the undercoordinated edges of graphene and the zigzag versus arm-chair configurations warrant comprehensive studies. The availability of well-defined pristine graphene starting materials in large quantities remains a key obstacle to the advancement of synthetic graphene chemistry.
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Affiliation(s)
- Jaehyeung Park
- Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, Massachusetts 01854, United States
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, Massachusetts 01854, United States
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Abstract
We report that proteins labeled with fluorescein-doped silica nanoparticles (FSNPs) showed drastically different fouling behavior than those labeled with the fluorescein dye. Arrays of polymer films were covalently immobilized on silicon wafers and were treated with protein conjugated on FSNPs. Fluorescence imaging showed that the protein-FSNP conjugate adsorbed strongly on hydrophilic polymers such as poly(ethylene oxide) (PEO) and weakly on hydrophobic polymers such as polystyrene (PS), and the extent of adsorption decreased with increasing hydrophobicity of the polymer film. Thus, carbohydrate microarrays probed with FSNP-labeled lectin showed significantly enhanced signals when PS was used as the antifouling coating than when PEO was used, or when using bovine serum albumin as the blocking agent.
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Affiliation(s)
- Hui Wang
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854
| | - Qi Tong
- Department of Chemistry, Portland State University, Portland, OR 97207
| | - Mingdi Yan
- Department of Chemistry, University of Massachusetts Lowell, Lowell, MA 01854
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27
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Tauhardt L, Kempe K, Gottschaldt M, Schubert US. Poly(2-oxazoline) functionalized surfaces: from modification to application. Chem Soc Rev 2013; 42:7998-8011. [DOI: 10.1039/c3cs60161g] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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28
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Zheng Z, Zhao H, Fa W, He W, Wong KW, Kwok RWM, Lau WM. Construction of cross-linked polymer films covalently attached on silicon substrate via a self-assembled monolayer. RSC Adv 2013. [DOI: 10.1039/c3ra40949j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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29
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Abstract
We report a new type of microarray, based on glyconanoparticles (GNPs), to study glycan-lectin interactions. GNPs, synthesized by conjugating carbohydrate ligands on silica nanoparticles, were printed on a photoactive surface followed by covalent immobilization by light activation. The GNP microarrays could be probed by lectins labeled with fluorescein as well as fluorescein-doped silica nanoparticles (FSNPs). Results showed that FSNP as the label enhanced the signals for the higher affinity ligands than the lower ones.
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Affiliation(s)
- Qi Tong
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207
| | - Xin Wang
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207
| | - Hui Wang
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854
| | - Takuya Kubo
- Graduate School of Environment Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aobaku, Sendai 9808579, Japan
| | - Mingdi Yan
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207
- Department of Chemistry, University of Massachusetts Lowell, 1 University Ave., Lowell, MA 01854
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30
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Wang H, Lee IH, Yan M. A general method to determine ionization constants of responsive polymer thin films. J Colloid Interface Sci 2012; 365:178-83. [PMID: 21962542 PMCID: PMC4034268 DOI: 10.1016/j.jcis.2011.08.081] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 08/26/2011] [Accepted: 08/29/2011] [Indexed: 02/05/2023]
Abstract
A general method has been developed to determine the ionization constants of polymer thin films based on the stimuli-responsiveness of the polymer. Robust polymer films were fabricated on silicon wafers and gold slides using perfluorophenyl azide (PFPA) as the coupling agent. The ionization constants were measured by a number of techniques including ellipsometry, dynamic contact angle goniometry, and surface plasmon resonance imaging (SPRi). Using poly(4-vinylpyridine) (P4VP) as the model system, P4VP thin films were fabricated and the ionization constants of the films were measured taking advantage of the pH responsive property of the polymer. The pK(a) determined by ellipsometry, ~4.0, reflects the swelling of the polymer film in response to pH. The pK(a) value calculated from the dynamic contact angle measurements, ~5.0, relies on the change in hydrophilicity/hydrophobicity of the films as the polymer undergoes protonation/deprotonation. The pK(a) value measured by SPRi, ~4.9, monitors in situ the change of refractive index of the polymer thin film as it swells upon protonation. This was the first example where SPRi was used to measure the ionization constants of polymers.
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Affiliation(s)
- Hui Wang
- Department of Chemistry, Portland State University, PO Box 751, Portland, OR, U.S.A. 97207-0751
| | - Irene H. Lee
- Department of Chemistry, Portland State University, PO Box 751, Portland, OR, U.S.A. 97207-0751
| | - Mingdi Yan
- Department of Chemistry, Portland State University, PO Box 751, Portland, OR, U.S.A. 97207-0751
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Zhang Y, Su Y, Chen W, Peng J, Dong Y, Jiang Z, Liu H. Appearance of poly(ethylene oxide) segments in the polyamide layer for antifouling nanofiltration membranes. J Memb Sci 2011. [DOI: 10.1016/j.memsci.2011.08.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Wang H, Li L, Tong Q, Yan M. Evaluation of photochemically immobilized poly(2-ethyl-2-oxazoline) thin films as protein-resistant surfaces. ACS APPLIED MATERIALS & INTERFACES 2011; 3:3463-71. [PMID: 21834589 PMCID: PMC3184304 DOI: 10.1021/am200690s] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Poly(2-ethyl-2-oxazoline) (PEOX) of various molecular weights were covalently immobilized on silicon wafers and gold slides to form protein-resistant surfaces via a fast and general photocoupling chemistry based on the CH insertion reaction of light-activated perfluorophenyl azide (PFPA). The thicknesses of the immobilized PEOX films ranged from 23 to 80 Å for molecular weight of 5000 to 500,000, and the grafting density reached 3.2 × 10(-3) Å(-2) for PEOX 5000. The protein-resistant property of the films was studied using bovine serum albumin (BSA) by fluorescence imaging, ellipsometry, and surface plasmon resonance imaging (SPRi). The fluorescence imaging and ellipsometry studies showed the largest amount of BSA adsorbed on PEOX 5000 and the smallest on PEOX 500,000. This was consistent with the kinetic analysis of BSA adsorption by SPRi showing that PEOX 5000 exhibited the fastest association rate and the slowest dissociation rate whereas PEOX 500,000 had the slowest association rate and the fastest dissociation rate. The PEOX film was then applied in the fabrication of carbohydrate microarrays to reduce the nonspecific adsorption of lectins and thus the background noises. Results showed that the microarray signals were significantly enhanced when the PEOX film was used.
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Affiliation(s)
- Hui Wang
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
| | - Liling Li
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
| | - Qi Tong
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
| | - Mingdi Yan
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, OR 97207-0751
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Kubo T, Wang X, Tong Q, Yan M. Polymer-based photocoupling agent for the efficient immobilization of nanomaterials and small molecules. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:9372-8. [PMID: 21699222 PMCID: PMC3148948 DOI: 10.1021/la201324h] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A highly efficient photocoupling agent, based on perfluorophenylazide (PFPA)-conjugated polyallylamine (PAAm), was developed for the efficient immobilization of polymers, nanoparticles, graphene, and small molecules. The conjugate, PAAm-PFPA, was synthesized, and the percentage of the photoactive moiety, PFPA, can be controlled by the ratio of the two components in the synthesis. By treating epoxy-functionalized wafers with PAAm-PFPA, photoactive surfaces were generated. Compared with the PFPA surface, these polymer-based photocoupling matrix resulted in significantly enhanced immobilization efficiencies, especially for nanomaterials and small molecules. Thus, polystyrene nanoparticles (PS NPs) and alkyl-functionalized silica nanoparticles (SNPs) were successfully immobilized on the PAAm-PFPA surface, resulting in a high material density. Graphene flakes patterned on the PAAm-PFPA surface showed improved feature resolution in addition to a higher material density compared to that of flakes immobilized on the PFPA surface. Furthermore, 2-O-α-D-mannopyranosyl-D-mannopyranose (Man2) immobilized on the PAAm-PFPA surface exhibited significantly enhanced signals when treated with lectin concanavalin A (Con A).
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Affiliation(s)
- Takuya Kubo
- Department of Chemistry, Portland State University, 1719 SW 10th Ave. Portland, OR 97201
- Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aobaku, Sendai 9808579, Japan
| | - Xin Wang
- Department of Chemistry, Portland State University, 1719 SW 10th Ave. Portland, OR 97201
| | - Qi Tong
- Department of Chemistry, Portland State University, 1719 SW 10th Ave. Portland, OR 97201
| | - Mingdi Yan
- Department of Chemistry, Portland State University, 1719 SW 10th Ave. Portland, OR 97201
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Gosecka M, Griffete N, Mangeney C, Chehimi MM, Slomkowski S, Basinska T. Preparation and optical properties of novel bioactive photonic crystals obtained from core-shell poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) microspheres. Colloid Polym Sci 2011; 289:1511-1518. [PMID: 21892246 PMCID: PMC3140920 DOI: 10.1007/s00396-011-2447-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 05/06/2011] [Accepted: 05/11/2011] [Indexed: 11/15/2022]
Abstract
Optical properties of polymer microspheres with polystyrene cores and polyglycidol-enriched shells poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGL) particles with number average diameters Dn determined by scanning electron microscopy equal 237 and 271 nm), were studied before and after immobilization of ovalbumin. The particles were synthesized by emulsifier-free emulsion copolymerization of styrene and polyglycidol macromonomer (poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol)) initiated with potassium persulfate. Molar fraction of polyglycidol units in the interfacial layer of the microspheres determined by XPS was equal 42.6 and 34.0%, for the particles with Dn equal 137 and 271 nm, respectively. Colloidal crystals from the aforementioned particles were prepared by deposition of particle suspensions on the glass slides and subsequent evaporation of water. It was found that optical properties of colloidal crystals from the P(S/PGL) microspheres strongly depend on modification of their interfacial layer by covalent immobilization of ovalbumin. The coating of particles with ovalbumin resulted in decreasing their refractive index from 1.58 to 1.52.
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Liu Y, Guo CX, Hu W, Lu Z, Li CM. Sensitive protein microarray synergistically amplified by polymer brush-enhanced immobilizations of both probe and reporter. J Colloid Interface Sci 2011; 360:593-9. [PMID: 21640998 DOI: 10.1016/j.jcis.2011.05.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 05/09/2011] [Accepted: 05/10/2011] [Indexed: 01/28/2023]
Abstract
Great challenge remains to continuously improve sensitivity of protein microarrays for broad applications. A copolymer brush is in situ synthesized on both substrate and silica nanoparticle (SNP) surface to efficiently immobilize probe and reporter protein respectively for synergistic amplification of protein microarray signals. As a demonstration, sandwich immunoassay for a cancer biomarker carcinoembryonic antigen (CEA) detection is performed on microarray platform, showing a limit of detection (LOD) of 10 pg/ml and dynamic range of 10 pg/ml to 100 ng/ml. Two orders improvement of LOD is achieved in comparison to the small crosslinker-activated substrate. The improved sensitivity is attributed to not only the high immobilization amount of both probe and reporter but also the favorite protein binding orientations offered by the flexible brushes. This work provides a universal approach to inexpensively and significantly improve protein microarray sensitivity.
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Affiliation(s)
- Yingshuai Liu
- Institute for Clean Energy & Advanced Materials, Southwest University, Chongqing 400715, PR China
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Deng L, Norberg O, Uppalapati S, Yan M, Ramström O. Stereoselective synthesis of light-activatable perfluorophenylazide-conjugated carbohydrates for glycoarray fabrication and evaluation of structural effects on protein binding by SPR imaging. Org Biomol Chem 2011; 9:3188-98. [PMID: 21423935 PMCID: PMC4030401 DOI: 10.1039/c1ob05040k] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of light-activatable perfluorophenylazide (PFPA)-conjugated carbohydrate structures have been synthesized and applied to glycoarray fabrication. The glycoconjugates were structurally varied with respect to anomeric attachment, S-, and O-linked carbohydrates, respectively, as well as linker structure and length. Efficient stereoselective synthetic routes were developed, leading to the formation of the PFPA-conjugated structures in good yields over few steps. The use of glycosyl thiols as donors proved especially efficient and provided the final compounds in up to 70% total yield with high anomeric purities. PFPA-based photochemistry was subsequently used to generate carbohydrate arrays on a polymeric surface, and surface plasmon resonance imaging (SPRi) was applied for evaluation of carbohydrate-protein interactions using the plant lectin Concanavalin A (Con A) as a probe. The results indicate better performance and equal efficiency of S- and O-linked structures with intermediate linker length.
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Affiliation(s)
- Lingquan Deng
- Department of Chemistry, KTH - Royal Institute of Technology, Teknikringen 30, S-10044, Stockholm, Sweden
| | - Oscar Norberg
- Department of Chemistry, KTH - Royal Institute of Technology, Teknikringen 30, S-10044, Stockholm, Sweden
| | - Suji Uppalapati
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Mingdi Yan
- Department of Chemistry, KTH - Royal Institute of Technology, Teknikringen 30, S-10044, Stockholm, Sweden
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, Oregon, 97207-0751, USA
| | - Olof Ramström
- Department of Chemistry, KTH - Royal Institute of Technology, Teknikringen 30, S-10044, Stockholm, Sweden
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Liu LH, Yan M. Perfluorophenyl azides: new applications in surface functionalization and nanomaterial synthesis. Acc Chem Res 2010; 43:1434-43. [PMID: 20690606 PMCID: PMC2982936 DOI: 10.1021/ar100066t] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A major challenge in materials science is the ongoing search for coupling agents that are readily synthesized, capable of versatile chemistry, able to easily functionalize materials and surfaces, and efficient in covalently linking organic and inorganic entities. A decade ago, we began a research program investigating perfluorophenylazides (PFPA) as the coupling agents in surface functionalization and nanomaterial synthesis. The p-substituted PFPAs are attractive heterobifunctional coupling agents because of their two distinct and synthetically distinguishable reactive centers: (i) the fluorinated phenylazide, which is capable of forming stable covalent adducts, and (ii) the functional group R, which can be tailored through synthesis. Two approaches have been undertaken for material synthesis and surface functionalization. The first method involves synthesizing PFPA bearing the first molecule or material with a functional linker R and then attaching the resulting PFPA to the second material by activating the azido group. In the second approach, the material surface is first functionalized with PFPA via functional center R, and coupling of the second molecule or material is achieved with the surface azido groups. In this Account, we review the design and protocols of the two approaches, providing examples in which PFPA derivatives were successfully used in material surface functionalization, ligand conjugation, and the synthesis of hybrid nanomaterials. The methods developed have proved to be general and versatile, and they are applicable to a wide range of materials (especially those that lack reactive functional groups or are difficult to derivatize) and to various substrates of polymers, oxides, carbon materials, and metal films. The coupling chemistry can be initiated by light, heat, and electrons. Patterned structures can be generated by selectively activating the areas of interest. Furthermore, the process is easy to perform, and light activation occurs in minutes, greatly facilitating the efficiency of the reaction. PFPAs indeed demonstrate many benefits as versatile surface coupling agents and offer opportunities for further exploration.
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Affiliation(s)
- Li-Hong Liu
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, Oregon 97207-0751
| | - Mingdi Yan
- Department of Chemistry, Portland State University, P.O. Box 751, Portland, Oregon 97207-0751
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