1
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Huang X, Jin K, Yang S, Zeng J, Zhou H, Zhang R, Xue J, Liu Y, Liu G, Peng H. Fabrication of polyvinylidene fluoride and acylthiourea composite membrane and its adsorption performance and mechanism on silver ions. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2023]
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2
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Ciccone L, Nencetti S, Marino M, Battocchio C, Iucci G, Venditti I, Marsotto M, Montalesi E, Socci S, Bargagna B, Orlandini E. Pterostilbene fluorescent probes as potential tools for targeting neurodegeneration in biological applications. J Enzyme Inhib Med Chem 2022; 37:1812-1820. [PMID: 35758192 PMCID: PMC9246042 DOI: 10.1080/14756366.2022.2091556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Several epidemiological studies suggest that a diet rich in fruit and vegetables reduces the incidence of neurodegenerative diseases. Resveratrol (Res) and its dimethylated metabolite, pterostibene (Ptb), have been largely studied for their neuroprotective action. The clinical use of Res is limited because of its rapid metabolism and its poor bioavailability. Ptb with two methoxy groups and one hydroxyl group has a good membrane permeability, metabolic stability and higher in vivo bioavailability in comparison with Res. The metabolism and pharmacokinetics of Ptb are still sparse, probably due to the lack of tools that allow following the Ptb destiny both in living cells and in vivo. In this contest, we propose two Ptb fluorescent derivatives where Ptb has been functionalised by benzofurazan and rhodamine-B-isothiocyanate, compounds 1 and 2, respectively. Here, we report the synthesis, the optical and structural characterisation of 1 and 2, and, their putative cytotoxicity in two different cell lines.
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Affiliation(s)
- Lidia Ciccone
- Department of Pharmacy, University of Pisa, Pisa, Italy.,CISUP - Centre for Instrumentation Sharing, University of Pisa, Pisa, Italy
| | - Susanna Nencetti
- Department of Pharmacy, University of Pisa, Pisa, Italy.,CISUP - Centre for Instrumentation Sharing, University of Pisa, Pisa, Italy
| | - Maria Marino
- Department of Science, University Roma Tre, Rome, Italy
| | | | | | - Iole Venditti
- Department of Science, University Roma Tre, Rome, Italy
| | | | | | - Simone Socci
- Department of Earth Science, University of Pisa, Pisa, Italy
| | | | - Elisabetta Orlandini
- Department of Earth Science, University of Pisa, Pisa, Italy.,Research Centre E. Piaggio, University of Pisa, Pisa, Italy
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3
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In situ discovery on the formation of supported silver catalysts for ethylene epoxidation. ADV POWDER TECHNOL 2022. [DOI: 10.1016/j.apt.2022.103732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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4
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Xie T, Brady A, Velarde C, Vaccarello DN, Callahan NW, Marino JP, Orski SV. Selective C-Terminal Conjugation of Protease-Derived Native Peptides for Proteomic Measurements. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:9119-9128. [PMID: 35856835 DOI: 10.1021/acs.langmuir.2c00359] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Bottom-up proteomic experiments often require selective conjugation or labeling of the N- and/or C-termini of peptides resulting from proteolytic digestion. For example, techniques based on surface fluorescence imaging are emerging as a promising route to high-throughput protein sequencing but require the generation of peptide surface arrays immobilized through single C-terminal point attachment while leaving the N-terminus free. While several robust approaches are available for selective N-terminal conjugation, it has proven to be much more challenging to implement methods for selective labeling or conjugation of the C-termini that can discriminate between the C-terminal carboxyl group and other carboxyl groups on aspartate and glutamate residues. Further, many approaches based on conjugation through amide bond formation require protection of the N-terminus to avoid unwanted cross-linking reactions. To overcome these challenges, herein, we describe a new strategy for single-point selective immobilization of peptides generated by protease digestion via the C-terminus. The method involves immobilization of peptides via lysine amino acids which are found naturally at the C-terminal end of cleaved peptides from digestions of certain serine endoproteinases, like LysC. This lysine and the N-terminus, the sole two primary amines in the peptide fragments, are chemically reacted with a custom phenyl isothiocyanate (EPITC) that contains an alkyne handle. Subsequent exposure of the double-modified peptides to acid selectively cleaves the N-terminal amino acid, while the modified C-terminus lysine remains unchanged. The alkyne-modified peptides with free N-termini can then be immobilized on an azide surface through standard click chemistry. Using this general approach, surface functionalization is demonstrated using a combination of X-ray photoelectron spectroscopy (XPS), ellipsometry, and atomic force microscopy (AFM).
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Affiliation(s)
- Tian Xie
- National Institute of Standards & Technology, Gaithersburg, Maryland 20899, United States
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
- Georgetown University, Washington, District of Columbia, 20057, United States
| | - Alexandria Brady
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
| | - Cecilia Velarde
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
| | - David N Vaccarello
- National Institute of Standards & Technology, Gaithersburg, Maryland 20899, United States
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
| | - Nicholas W Callahan
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
| | - John P Marino
- National Institute of Standards & Technology, Gaithersburg, Maryland 20899, United States
- University of Maryland - Institute for Bioscience and Biotechnology Research, Rockville, Maryland 20850, United States
| | - Sara V Orski
- National Institute of Standards & Technology, Gaithersburg, Maryland 20899, United States
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5
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Vesel A, Zaplotnik R, Primc G, Mozetič M, Katan T, Kargl R, Mohan T, Kleinschek KS. Rapid Functionalization of Polytetrafluorethylene (PTFE) Surfaces with Nitrogen Functional Groups. Polymers (Basel) 2021; 13:4301. [PMID: 34960856 PMCID: PMC8708819 DOI: 10.3390/polym13244301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 11/16/2022] Open
Abstract
The biocompatibility of body implants made from polytetrafluoroethylene (PTFE) is inadequate; therefore, the surface should be grafted with biocompatible molecules. Because PTFE is an inert polymer, the adhesion of the biocompatible film may not be appropriate. Therefore, the PFTE surface should be modified to enable better adhesion, preferably by functionalization with amino groups. A two-step process for functionalization of PTFE surface is described. The first step employs inductively coupled hydrogen plasma in the H-mode and the second ammonia plasma. The evolution of functional groups upon treatment with ammonia plasma in different modes is presented. The surface is saturated with nitrogen groups within a second if ammonia plasma is sustained in the H-mode at the pressure of 35 Pa and forward power of 200 W. The nitrogen-rich surface film persists for several seconds, while prolonged treatment causes etching. The etching is suppressed but not eliminated using pulsed ammonia plasma at 35 Pa and 200 W. Ammonia plasma in the E-mode at the same pressure, but forward power of 25 W, causes more gradual functionalization and etching was not observed even at prolonged treatments up to 100 s. Detailed investigation of the XPS spectra enabled revealing the surface kinetics for all three cases.
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Affiliation(s)
- Alenka Vesel
- Department of Surface Engineering, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; (R.Z.); (G.P.); (M.M.)
| | - Rok Zaplotnik
- Department of Surface Engineering, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; (R.Z.); (G.P.); (M.M.)
| | - Gregor Primc
- Department of Surface Engineering, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; (R.Z.); (G.P.); (M.M.)
| | - Miran Mozetič
- Department of Surface Engineering, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; (R.Z.); (G.P.); (M.M.)
| | - Tadeja Katan
- Institute for Chemistry and Technology of Biobased Systems, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; (T.K.); (R.K.); (T.M.); (K.S.K.)
| | - Rupert Kargl
- Institute for Chemistry and Technology of Biobased Systems, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; (T.K.); (R.K.); (T.M.); (K.S.K.)
| | - Tamilselvan Mohan
- Institute for Chemistry and Technology of Biobased Systems, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; (T.K.); (R.K.); (T.M.); (K.S.K.)
| | - Karin Stana Kleinschek
- Institute for Chemistry and Technology of Biobased Systems, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria; (T.K.); (R.K.); (T.M.); (K.S.K.)
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6
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Geißler D, Nirmalananthan-Budau N, Scholtz L, Tavernaro I, Resch-Genger U. Analyzing the surface of functional nanomaterials-how to quantify the total and derivatizable number of functional groups and ligands. Mikrochim Acta 2021; 188:321. [PMID: 34482449 PMCID: PMC8418596 DOI: 10.1007/s00604-021-04960-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 08/08/2021] [Indexed: 12/04/2022]
Abstract
Functional nanomaterials (NM) of different size, shape, chemical composition, and surface chemistry are of increasing relevance for many key technologies of the twenty-first century. This includes polymer and silica or silica-coated nanoparticles (NP) with covalently bound surface groups, semiconductor quantum dots (QD), metal and metal oxide NP, and lanthanide-based NP with coordinatively or electrostatically bound ligands, as well as surface-coated nanostructures like micellar encapsulated NP. The surface chemistry can significantly affect the physicochemical properties of NM, their charge, their processability and performance, as well as their impact on human health and the environment. Thus, analytical methods for the characterization of NM surface chemistry regarding chemical identification, quantification, and accessibility of functional groups (FG) and surface ligands bearing such FG are of increasing importance for quality control of NM synthesis up to nanosafety. Here, we provide an overview of analytical methods for FG analysis and quantification with special emphasis on bioanalytically relevant FG broadly utilized for the covalent attachment of biomolecules like proteins, peptides, and oligonucleotides and address method- and material-related challenges and limitations. Analytical techniques reviewed include electrochemical titration methods, optical assays, nuclear magnetic resonance and vibrational spectroscopy, as well as X-ray based and thermal analysis methods, covering the last 5-10 years. Criteria for method classification and evaluation include the need for a signal-generating label, provision of either the total or derivatizable number of FG, need for expensive instrumentation, and suitability for process and production control during NM synthesis and functionalization.
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Affiliation(s)
- Daniel Geißler
- Bundesanstalt für Materialforschung und -prüfung (BAM), Division Biophotonics (BAM-1.2), Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Nithiya Nirmalananthan-Budau
- Bundesanstalt für Materialforschung und -prüfung (BAM), Division Biophotonics (BAM-1.2), Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Lena Scholtz
- Bundesanstalt für Materialforschung und -prüfung (BAM), Division Biophotonics (BAM-1.2), Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Isabella Tavernaro
- Bundesanstalt für Materialforschung und -prüfung (BAM), Division Biophotonics (BAM-1.2), Richard-Willstätter-Str. 11, 12489, Berlin, Germany
| | - Ute Resch-Genger
- Bundesanstalt für Materialforschung und -prüfung (BAM), Division Biophotonics (BAM-1.2), Richard-Willstätter-Str. 11, 12489, Berlin, Germany.
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7
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A surface functionalized with per-(6-amino-6-deoxy)-β-cyclodextrin for potential organic pollutant removal from water. Carbohydr Polym 2020; 233:115865. [DOI: 10.1016/j.carbpol.2020.115865] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 12/16/2019] [Accepted: 01/12/2020] [Indexed: 12/28/2022]
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8
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Abdelhameed M, Aly S, Maity P, Manni E, Mohammed OF, Charpentier PA. Impact of the chemical nature and position of spacers on controlling the optical properties of silicon quantum dots. Phys Chem Chem Phys 2019; 21:17096-17108. [PMID: 31339151 DOI: 10.1039/c9cp03537k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The unique properties of silicon quantum dots (SQDs), including intriguing optical properties, biocompatibility, and ease of surface modification have made them excellent candidates for a variety of optoelectronic and biomedical applications. Unfortunately, the low quantum efficiency (QE), unstable photoluminescence, and poor colloidal stability of SQDs have hindered their wide applicability. Herein, we report the synthesis of four assemblies of SQDs (1.6-1.8 nm average diameter) functionalized with fluorescein dye through isothiocyanate (-NCS) and carboxylate (COO-) spacers in the benzene ring of the fluorescein to produce the dyads Am-SQD-Fl, DiAm-SQD-Fl, urea-SQD-Fl, and SQD-Fl. The photophysical measurements showed that the spacer played a key role in directing and controlling the optical properties of SQDs dyads, with the isothiocyanate spacer leading to a significant improvement in the QE of the dyad systems up to 65% and extending their photostability for at least one year. The interactions between the SQDs and fluorescein in the dyads Am-SQD-Fl, DiAm-SQD-Fl, and SQD-Fl were found to mainly proceed through photoinduced electron transfer at different rates, while energy transfer was confirmed to be the predominant process in the dyad urea-SQD-Fl. To demonstrate the suitability of the functionalized SQDs for bioimaging applications, the water-soluble dyads were examined for fluorescence imaging of human bone cancerous U2OS cells.
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Affiliation(s)
- Mohammed Abdelhameed
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario N6A 5B9, Canada.
| | - Shawkat Aly
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario N6A 5B9, Canada.
| | - Partha Maity
- Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Emad Manni
- Department of Biochemistry, Western University, London, Ontario N6A 5B9, Canada
| | - Omar F Mohammed
- Physical Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia.
| | - Paul A Charpentier
- Department of Chemical and Biochemical Engineering, Western University, London, Ontario N6A 5B9, Canada.
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9
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Huang X, Cao X, Wang W, Zhong H, Cao ZF. Investigation of removal of Ag(I) from aqueous solution by a novel chelating resin containing acyl and thiourea groups. J DISPER SCI TECHNOL 2019. [DOI: 10.1080/01932691.2018.1470011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Xiaoping Huang
- College of Chemistry and Chemical Engineering, Central South University, Yuelu District, Changsha, Hunan, China
| | - Xiaoyu Cao
- College of Chemistry and Chemical Engineering, Central South University, Yuelu District, Changsha, Hunan, China
| | - Weihong Wang
- College of Chemistry and Chemical Engineering, Central South University, Yuelu District, Changsha, Hunan, China
| | - Hong Zhong
- College of Chemistry and Chemical Engineering, Central South University, Yuelu District, Changsha, Hunan, China
| | - Zhan-Fang Cao
- College of Chemistry and Chemical Engineering, Central South University, Yuelu District, Changsha, Hunan, China
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10
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Nilam M, Ahmed M, Alnajjar MA, Hennig A. Characterization of mixed-ligand shells on gold nanoparticles by transition metal and supramolecular surface probes. Analyst 2019; 144:579-586. [DOI: 10.1039/c8an01181h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two simple colorimetric and fluorimetric methods to probe the surface of gold nanoparticles.
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Affiliation(s)
- Mohamed Nilam
- Department of Life Sciences and Chemistry
- Jacobs University Bremen
- 28759 Bremen
- Germany
| | - Mostafa Ahmed
- Department of Life Sciences and Chemistry
- Jacobs University Bremen
- 28759 Bremen
- Germany
- Department of Chemistry
| | - Mohammad A. Alnajjar
- Department of Life Sciences and Chemistry
- Jacobs University Bremen
- 28759 Bremen
- Germany
| | - Andreas Hennig
- Department of Life Sciences and Chemistry
- Jacobs University Bremen
- 28759 Bremen
- Germany
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11
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Fujimori T, Nakamura M, Takaoka M, Shiota K, Kitajima Y. Synergetic inhibition of thermochemical formation of chlorinated aromatics by sulfur and nitrogen derived from thiourea: Multielement characterizations. JOURNAL OF HAZARDOUS MATERIALS 2016; 311:43-50. [PMID: 26954475 DOI: 10.1016/j.jhazmat.2016.02.054] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 01/25/2016] [Accepted: 02/24/2016] [Indexed: 06/05/2023]
Abstract
Nitrogen and sulfur (N/S)-containing compounds inhibit the formation of polychlorinated dibenzo-p-dioxins (PCDDs) and furans (PCDFs) in thermal processes. However, few studies have examined the inhibition mechanisms of N/S-containing compounds. In the present study, we focused on thiourea [(NH2)2CS] as such a compound and investigated its inhibition effects and mechanisms. The production of PCDD/Fs, polychlorinated biphenyls (PCBs), and chlorobenzenes (CBzs) were inhibited by >99% in the model fly ash in the presence of 1.0% thiourea after heating at 300 °C. Experimental results using real fly ash series were indicative of the thermal destruction of these chlorinated aromatics by thiourea. Multielement characterization using K-edge X-ray absorption fine structures of copper, chlorine, sulfur, nitrogen, and carbon revealed three possible inhibition paths, namely, (a) sulfidization of the copper catalyst to CuS, Cu2S, and CuSO4; (b) blocking the chlorination of carbon via the reaction of chlorine with N-containing compounds to generate ammonium chloride and other minor compounds; and (c) changing the carbon frame involved in attacking the carbon matrix by sulfur and nitrogen. Thus, thiourea plays a role as a sulfur and nitrogen donor to achieve multiple and synergistic inhibition of chlorinated aromatics. Our results suggest that other N/S-containing inhibitors function based on similar mechanisms.
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Affiliation(s)
- Takashi Fujimori
- Department of Global Ecology, Graduate School of Global Environmental Studies, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan; Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan.
| | - Madoka Nakamura
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan
| | - Masaki Takaoka
- Department of Global Ecology, Graduate School of Global Environmental Studies, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan; Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan
| | - Kenji Shiota
- Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Nisikyo-ku, Kyoto 615-8540, Japan
| | - Yoshinori Kitajima
- Photon Factory, Institute of Materials Structure Science (IMSS), High Energy Accelerator Research Organization (KEK), Oho 1-1, Tsukuba, Ibaraki 305-0801, Japan
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12
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Wang S, Yin D, Wang W, Shen X, Zhu JJ, Chen HY, Liu Z. Targeting and Imaging of Cancer Cells via Monosaccharide-Imprinted Fluorescent Nanoparticles. Sci Rep 2016; 6:22757. [PMID: 26948803 PMCID: PMC4780104 DOI: 10.1038/srep22757] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/23/2016] [Indexed: 02/07/2023] Open
Abstract
The recognition of cancer cells is a key for cancer diagnosis and therapy, but the specificity highly relies on the use of biorecognition molecules particularly antibodies. Because biorecognition molecules suffer from some apparent disadvantages, such as hard to prepare and poor storage stability, novel alternatives that can overcome these disadvantages are highly important. Here we present monosaccharide-imprinted fluorescent nanoparticles (NPs) for targeting and imaging of cancer cells. The molecularly imprinted polymer (MIP) probe was fluorescein isothiocyanate (FITC) doped silica NPs with a shell imprinted with sialic acid, fucose or mannose as the template. The monosaccharide-imprinted NPs exhibited high specificity toward the target monosaccharides. As the template monosaccharides used are over-expressed on cancer cells, these monosaccharide-imprinted NPs allowed for specific targeting cancer cells over normal cells. Fluorescence imaging of human hepatoma carcinoma cells (HepG-2) over normal hepatic cells (L-02) and mammary cancer cells (MCF-7) over normal mammary epithelial cells (MCF-10A) by these NPs was demonstrated. As the imprinting approach employed herein is generally applicable and highly efficient, monosaccharide-imprinted NPs can be promising probes for targeting cancer cells.
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Affiliation(s)
- Shuangshou Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Danyang Yin
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Wenjing Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xiaojing Shen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jun-Jie Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hong-Yuan Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Zhen Liu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.,Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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13
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Fischer T, Dietrich PM, Unger WES, Rurack K. Multimode Surface Functional Group Determination: Combining Steady-State and Time-Resolved Fluorescence with X-ray Photoelectron Spectroscopy and Absorption Measurements for Absolute Quantification. Anal Chem 2016; 88:1210-7. [DOI: 10.1021/acs.analchem.5b03468] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tobias Fischer
- Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Paul M. Dietrich
- Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Wolfgang E. S. Unger
- Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Knut Rurack
- Bundesanstalt für Materialforschung und −prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
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14
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Dietrich PM, Streeck C, Glamsch S, Ehlert C, Lippitz A, Nutsch A, Kulak N, Beckhoff B, Unger WES. Quantification of Silane Molecules on Oxidized Silicon: Are there Options for a Traceable and Absolute Determination? Anal Chem 2015; 87:10117-24. [DOI: 10.1021/acs.analchem.5b02846] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- P. M. Dietrich
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - C. Streeck
- Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany
| | - S. Glamsch
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
- Institut
für Chemie und Biochemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195 Berlin, Germany
| | - C. Ehlert
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
- Institut
für Chemie, Universität Potsdam, Karl-Liebknecht-Straße 24-25, 14476 Potsdam, Germany
| | - A. Lippitz
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - A. Nutsch
- Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany
| | - N. Kulak
- Institut
für Chemie und Biochemie, Freie Universität Berlin, Fabeckstr. 34/36, 14195 Berlin, Germany
| | - B. Beckhoff
- Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany
| | - W. E. S. Unger
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12205 Berlin, Germany
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15
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Chen S, Itoh Y, Masuda T, Shimizu S, Zhao J, Ma J, Nakamura S, Okuro K, Noguchi H, Uosaki K, Aida T. Ionic interactions. Subnanoscale hydrophobic modulation of salt bridges in aqueous media. Science 2015; 348:555-9. [PMID: 25931555 DOI: 10.1126/science.aaa7532] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Polar interactions such as electrostatic forces and hydrogen bonds play an essential role in biological molecular recognition. On a protein surface, polar interactions occur mostly in a hydrophobic environment because nonpolar amino acid residues cover ~75% of the protein surface. We report that ionic interactions on a hydrophobic surface are modulated by their subnanoscale distance to the surface. We developed a series of ionic head groups-appended self-assembled monolayers with C2, C6, C8, and C12 space-filling alkyl chains, which capture a dendritic guest via the formation of multiple salt bridges. The guest release upon protonolysis is progressively suppressed when its distance from the background hydrophobe changes from 1.2 (C2) to 0.2 (C12) nanometers, with an increase in salt bridge strength of ~3.9 kilocalories per mole.
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Affiliation(s)
- Shuo Chen
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yoshimitsu Itoh
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
| | - Takuya Masuda
- Global Research Center for Environment and Energy based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan
| | - Seishi Shimizu
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
| | - Jun Zhao
- Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China
| | - Jing Ma
- Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China
| | - Shugo Nakamura
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Kou Okuro
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hidenori Noguchi
- Global Research Center for Environment and Energy based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan. International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan. Graduate School of Chemical Science and Engineering, Hokkaido University, Sapporo 060-0810, Japan
| | - Kohei Uosaki
- Global Research Center for Environment and Energy based on Nanomaterials Science (GREEN), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan. International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba 305-0044, Japan. Graduate School of Chemical Science and Engineering, Hokkaido University, Sapporo 060-0810, Japan
| | - Takuzo Aida
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. RIKEN Center for Emergent Matter Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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16
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Fischer T, Dietrich PM, Streeck C, Ray S, Nutsch A, Shard A, Beckhoff B, Unger WES, Rurack K. Quantification of Variable Functional-Group Densities of Mixed-Silane Monolayers on Surfaces via a Dual-Mode Fluorescence and XPS Label. Anal Chem 2015; 87:2685-92. [DOI: 10.1021/ac503850f] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Tobias Fischer
- Division
1.9 Chemical and Optical Sensing, BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
| | - Paul M. Dietrich
- Division
6.8 Surface Analysis and Interfacial Chemistry, BAM Federal Institute for Materials Research and Testing, Unter den Eichen 44-46, 12203 Berlin, Germany
| | - Cornelia Streeck
- X-ray
and IR Spectrometry Group, Physikalisch-Technische Bundesanstalt PTB, Abbestrasse
2-12, 10587 Berlin, Germany
| | - Santanu Ray
- Surface
and Nanoanalysis Group, Analytical Science Division, National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Andreas Nutsch
- X-ray
and IR Spectrometry Group, Physikalisch-Technische Bundesanstalt PTB, Abbestrasse
2-12, 10587 Berlin, Germany
| | - Alex Shard
- Surface
and Nanoanalysis Group, Analytical Science Division, National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW, United Kingdom
| | - Burkhard Beckhoff
- X-ray
and IR Spectrometry Group, Physikalisch-Technische Bundesanstalt PTB, Abbestrasse
2-12, 10587 Berlin, Germany
| | - Wolfgang E. S. Unger
- Division
6.8 Surface Analysis and Interfacial Chemistry, BAM Federal Institute for Materials Research and Testing, Unter den Eichen 44-46, 12203 Berlin, Germany
| | - Knut Rurack
- Division
1.9 Chemical and Optical Sensing, BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse 11, 12489 Berlin, Germany
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17
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Vuori L, Leppiniemi J, Hannula M, Lahtonen K, Hirsimäki M, Nõmmiste E, Costelle L, Hytönen VP, Valden M. Biofunctional hybrid materials: bimolecular organosilane monolayers on FeCr alloys. NANOTECHNOLOGY 2014; 25:435603. [PMID: 25297847 DOI: 10.1088/0957-4484/25/43/435603] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Hybrid organic-inorganic interfaces are the key to functionalization of stainless steel (SS). We present a solution-based deposition method for fabricating uniform bimolecular organosilane monolayers on SS and show that their properties and functionalities can be further developed through site-specific biotinylation. We correlate molecular properties of the interface with its reactivity via surface sensitive synchrotron radiation mediated high-resolution photoelectron spectroscopy (HR-PES) and chemical derivatization (CD), and we demonstrate specific bonding of streptavidin proteins to the hybrid interface. The method facilitates efficient growth of uniform bimolecular organosilane monolayers on SS under ambient conditions without the need to prime the SS surface with vacuum-deposited inorganic buffer layers. The obtained insights into molecular bonding, orientation, and behaviour of surface-confined organofunctional silanes on SS enable a new generic approach to functionalization of SS surfaces with versatile nanomolecular organosilane layers.
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Affiliation(s)
- Leena Vuori
- Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, PO Box 692, FI-33101 Tampere, Finland
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18
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Nietzold C, Dietrich PM, Ivanov-Pankov S, Lippitz A, Gross T, Weigel W, Unger WES. Functional group quantification on epoxy surfaces by chemical derivatization (CD)-XPS. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5433] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Carolin Nietzold
- BAM Federal Institute for Materials Research and Testing; Unter den Eichen 87 12205 Berlin Germany
| | - Paul M. Dietrich
- BAM Federal Institute for Materials Research and Testing; Unter den Eichen 87 12205 Berlin Germany
| | | | - Andreas Lippitz
- BAM Federal Institute for Materials Research and Testing; Unter den Eichen 87 12205 Berlin Germany
| | - Thomas Gross
- BAM Federal Institute for Materials Research and Testing; Unter den Eichen 87 12205 Berlin Germany
| | | | - Wolfgang E. S. Unger
- BAM Federal Institute for Materials Research and Testing; Unter den Eichen 87 12205 Berlin Germany
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19
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Hecht M, Fischer T, Dietrich P, Kraus W, Descalzo AB, Unger WES, Rurack K. Fluorinated Boron-Dipyrromethene (BODIPY) Dyes: Bright and Versatile Probes for Surface Analysis. ChemistryOpen 2013; 2:25-38. [PMID: 24551526 PMCID: PMC3594589 DOI: 10.1002/open.201200039] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Indexed: 12/22/2022] Open
Abstract
A family of bright boron-dipyrromethene-type fluorophores with a high number of fluorine atoms (F-BODIPYs) has been developed and characterized by X-ray crystallography and optical spectroscopy. The introduction of 3,5-bis(trifluoromethyl)phenyl and pentafluorophenyl moieties significantly enhances the photostability of such dyes, yielding for instance photostable near-infrared (NIR) fluorophores that show emission maxima>750 nm, when the BODIPY's π system is extended with two (dimethylamino)styryl and (dimethylamino)naphthastyryl moieties, or green-emitting BODIPYs with fluorescence quantum yields of unity. When equipped with a suitable group that selectively reacts for instance with amines, F-BODIPYs can be used as potent dual labels for the quantification of primary amino groups on surfaces by X-ray photoelectron spectroscopy (XPS) and fluorescence, two powerful yet complementary tools for the analysis of organic surface functional groups. The advantage of reactive F-BODIPYs is that they allow a fast and non-destructive mapping of the labelled supports with conventional fluorescence scanners and a subsequent quantification of selected areas of the same sample by the potentially traceable XPS technique. The performance is exemplarily shown here for the assessment of the amino group density on SiO2 supports, one of the most common reactive silica supports, in particular, for standard microarray applications.
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Affiliation(s)
- Mandy Hecht
- Division 1.9 Sensor Materials, BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11, 12489 Berlin (Germany) E-mail:
| | - Tobias Fischer
- Division 1.9 Sensor Materials, BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11, 12489 Berlin (Germany) E-mail:
| | - Paul Dietrich
- Division 6.8 Surface Analysis and Interfacial Chemistry, BAM Federal Institute for Materials Research and Testing Unter den Eichen 44-46, 12203 Berlin (Germany)
| | - Werner Kraus
- Division 1.3 Structural Analysis, BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11, 12489 Berlin (Germany)
| | - Ana B Descalzo
- Division 1.9 Sensor Materials, BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11, 12489 Berlin (Germany) E-mail:
| | - Wolfgang E S Unger
- Division 6.8 Surface Analysis and Interfacial Chemistry, BAM Federal Institute for Materials Research and Testing Unter den Eichen 44-46, 12203 Berlin (Germany)
| | - Knut Rurack
- Division 1.9 Sensor Materials, BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Str. 11, 12489 Berlin (Germany) E-mail:
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20
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Azucena C, Eber FJ, Trouillet V, Hirtz M, Heissler S, Franzreb M, Fuchs H, Wege C, Gliemann H. New approaches for bottom-up assembly of tobacco mosaic virus-derived nucleoprotein tubes on defined patterns on silica- and polymer-based substrates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:14867-14877. [PMID: 22950722 DOI: 10.1021/la302774h] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The capability of some natural molecular building blocks to self-organize into defined supramolecular architectures is a versatile tool for nanotechnological applications. Their site-selective integration into a technical context, however, still poses a major challenge. RNA-directed self-assembly of tobacco mosaic virus-derived coat protein on immobilized RNA scaffolds presents a possibility to grow nucleoprotein nanotubes in place. Two new methods for their site-selective, bottom-up assembly are introduced. For this purpose, isothiocyanate alkoxysilane was used to activate oxidic surfaces for the covalent immobilization of DNA oligomers, which served as linkers for assembly-directing RNA. Patterned silanization of surfaces was achieved (1) on oxidic surfaces via dip-pen nanolithography and (2) on polymer surfaces (poly(dimethylsiloxane)) via selective oxidization by UV-light irradiation in air. Atomic force microscopy and X-ray photoelectron spectroscopy were used to characterize the surfaces. It is shown for the first time that the combination of the mentioned structuring methods and the isothiocyanate-based chemistry is appropriate (1) for the site-selective immobilization of nucleic acids and, thus, (2) for the formation of viral nanoparticles by bottom-up self-assembly after adding the corresponding coat proteins.
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Affiliation(s)
- Carlos Azucena
- Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
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21
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Hennig A, Borcherding H, Jaeger C, Hatami S, Würth C, Hoffmann A, Hoffmann K, Thiele T, Schedler U, Resch-Genger U. Scope and Limitations of Surface Functional Group Quantification Methods: Exploratory Study with Poly(acrylic acid)-Grafted Micro- and Nanoparticles. J Am Chem Soc 2012; 134:8268-76. [DOI: 10.1021/ja302649g] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Andreas Hennig
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | | | - Christian Jaeger
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | - Soheil Hatami
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | - Christian Würth
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | - Angelika Hoffmann
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | - Katrin Hoffmann
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
| | - Thomas Thiele
- PolyAn GmbH, Rudolf-Baschant-Strasse 2,
D-13086 Berlin, Germany
| | - Uwe Schedler
- PolyAn GmbH, Rudolf-Baschant-Strasse 2,
D-13086 Berlin, Germany
| | - Ute Resch-Genger
- BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Strasse
11, D-12489 Berlin, Germany
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22
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Vogt AP, Trouillet V, Greiner AM, Kaupp M, Geckle U, Barner L, Hofe T, Barner-Kowollik C. A Facile Route to Boronic Acid Functional Polymeric Microspheres via Epoxide Ring Opening. Macromol Rapid Commun 2012; 33:1108-13. [DOI: 10.1002/marc.201200144] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 03/22/2012] [Indexed: 11/10/2022]
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23
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Pippig F, Holländer A. Hydrogel Nanofilms for Biomedical Applications: Synthesis via Polycondensation Reactions. Macromol Biosci 2010; 10:1093-105. [DOI: 10.1002/mabi.201000052] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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24
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Dietrich PM, Horlacher T, Gross T, Wirth T, Castelli R, Shard AG, Alexander M, Seeberger PH, Unger WES. Surface analytical characterization of carbohydrate microarrays. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3255] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Dietrich PM, Graf N, Gross T, Lippitz A, Schüpbach B, Bashir A, Wöll C, Terfort A, Unger WES. Self-assembled monolayers of aromatic omega-aminothiols on gold: surface chemistry and reactivity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:3949-3954. [PMID: 20041682 DOI: 10.1021/la903293b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Amino-terminated self-assembled monolayers on gold substrates were studied by X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) measurements, and atomic force microscopy (AFM). Two different omega-amino-4,4'-terphenyl substituted alkanethiols of the general structure H(2)N-(C(6)H(4))(3)-(CH(2))(n)-SH (ATPn) were used: 2-(4''-amino-1,1':4',1''-terphenyl-4-yl)ethane-1-thiol (n = 2, ATP2) and 3-(4''-amino-1,1':4',1''-terphenyl-4-yl)propane-1-thiol (n = 3, ATP3). Moreover, the addressability of amino groups within the films was investigated by chemical derivatization of ATPn SAMs with 3,5-bis(trifluoromethyl)phenyl isothiocyanate (ITC) forming fluorinated thiourea ATPn-F films. Evaluation of high-resolution C 1s and N 1s XPS data revealed successful derivatization of at least 50% of surface amino species. Furthermore, it could be demonstrated by angle-resolved NEXAFS spectroscopy that chemical derivatization with ITC has no noticeable influence on the preferential upright orientation of the molecules in the SAMs.
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Affiliation(s)
- Paul M Dietrich
- BAM Bundesanstalt für Materialforschung und -prüfung, D-12203 Berlin, Germany
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