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Dong A, Lin L, Mu R, Li R, Li K, Wang C, Cao Y, Ling Y, Chen Y, Yang F, Pan X, Fu Q, Bao X. Modulating the Formation and Evolution of Surface Hydrogen Species on ZnO through Cr Addition. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00978] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Aiyi Dong
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Science, Dalian Maritime University, Dalian 116026, China
| | - Le Lin
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Rentao Mu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Rongtan Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Kun Li
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- School of Science, Dalian Maritime University, Dalian 116026, China
| | - Chao Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Yunjun Cao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Yunjian Ling
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Yuxiang Chen
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- University of Chinese Academy of Sciences, Beijing 100039, China
| | - Fan Yang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xiulian Pan
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Qiang Fu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Xinhe Bao
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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Mehmood Y, Khan IU, Shahzad Y, Khan RU, Khalid SH, Yousaf AM, Hussain T, Asghar S, Khalid I, Asif M, Shah SU. Amino-decorated mesoporous silica nanoparticles for controlled sofosbuvir delivery. Eur J Pharm Sci 2019; 143:105184. [PMID: 31846695 DOI: 10.1016/j.ejps.2019.105184] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/13/2019] [Accepted: 12/13/2019] [Indexed: 01/28/2023]
Abstract
The present study describes synthesis of amino-decorated mesoporous silica nanoparticles (MSNs) for sustained delivery and enhanced bioavailability of sofosbuvir. Sofosbuvir is active against hepatitis C virus and pharmaceutically classified as class III drug according to biopharmaceutics classification system (BCS). MSNs were synthesized using modified sol-gel method and the surface was decorated with amino functionalization. Drug loaded MSNs were also grafted with polyvinyl alcohol in order to compare it with the amino-decorated MSNs for sustained drug release. The prepared MSNs were extensively characterized and the optimized formulation was toxicologically and pharmacokinetically evaluated. The functionalized MSNs of 196 nm size entrapped 29.13% sofosbuvir in the pores, which was also confirmed by the decrease in surface area, pore volume and pore size. The drug-loaded amino-decorated MSNs revealed an improved thermal stability as confirmed by thermal analysis. Amino-decorated MSNs exhibited Fickian diffusion controlled sofosbuvir release as compared with non-functionalized and PVA grafted MSNs. Amino-decorated MSNs were deemed safe to use in Sprague-Dawley rats after 14-days exposure as confirmed by the toxicological studies. More interestingly, we achieved a 2-fold higher bioavailability of sofosbuvir in Sprague-Dawley rats in comparison with sofosbuvir alone, and the Tmax was delayed 3-times indicating a sustained release of sofosbuvir.
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Affiliation(s)
- Yasir Mehmood
- Deaprtment of Pharmaceutics, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Ikram Ullah Khan
- Deaprtment of Pharmaceutics, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan.
| | - Yasser Shahzad
- Department of Pharmacy, COMSATS University Islamabad, Lahore Campus, Lahore, Pakistan.
| | - Rizwan Ullah Khan
- Department of Pathology, Prince Faisal Oncology Centre, Buraydah Al Qassim, Saudi Arabia
| | - Syed Haroon Khalid
- Deaprtment of Pharmaceutics, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Abid Mehmood Yousaf
- Department of Pharmacy, COMSATS University Islamabad, Lahore Campus, Lahore, Pakistan
| | - Talib Hussain
- Department of Pharmacy, COMSATS University Islamabad, Lahore Campus, Lahore, Pakistan
| | - Sajid Asghar
- Deaprtment of Pharmaceutics, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Ikrima Khalid
- Deaprtment of Pharmaceutics, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Asif
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University Faisalabad, Faisalabad, Pakistan
| | - Shefaat Ullah Shah
- Department of Pharmaceutics, Faculty of Pharmacy, Gomal University, Dera Ismail Khan, Pakistan
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Wang Y, Sun Y, Wang J, Yang Y, Li Y, Yuan Y, Liu C. Charge-Reversal APTES-Modified Mesoporous Silica Nanoparticles with High Drug Loading and Release Controllability. ACS APPLIED MATERIALS & INTERFACES 2016; 8:17166-17175. [PMID: 27314423 DOI: 10.1021/acsami.6b05370] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this study, we demonstrate a facile strategy (DL-SF) for developing MSN-based nanosystems through drug loading (DL, using doxorubicin as a model drug) followed by surface functionalization (SF) of mesoporous silica nanoparticles (MSNs) via aqueous (3-aminopropyl)triethoxysilane (APTES) silylation. For comparison, a reverse functionalization process (i.e., SF-DL) was also studied. The pre-DL process allows for an efficient encapsulation (encapsulation efficiency of ∼75%) of an anticancer drug [doxorubicin (DOX)] inside MSNs, and post-SF allows in situ formation of an APTES outer layer to restrict DOX leakage under physiological conditions. This method makes it possible to tune the DOX release rate by increasing the APTES decoration density through variation of the APTES concentration. However, the SF-DL approach results in a rapid decrease in drug loading capacity with an increase in APTES concentration because of the formation of the APTES outer layer hampers the inner permeability of the DOX drug, resulting in a burst release similar to that of undecorated MSNs. The resulting DOX-loaded DL-SF MSNs present a slightly negatively charged surface under physiological conditions and become positively charged in and extracellular microenvironment of solid tumor due to the protonation effect under acidic conditions. These merits aid their maintenance of long-term stability in blood circulation, high cellular uptake by a kind of skin carcinoma cells, and an enhanced intracellular drug release behavior, showing their potential in the delivery of many drugs beyond anticancer chemotherapeutics.
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Affiliation(s)
- Yifeng Wang
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Yi Sun
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Jine Wang
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Yang Yang
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Yulin Li
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
- Shanghai Collaborative Innovation Center for Biomanufacturing, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Yuan Yuan
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
| | - Changsheng Liu
- Key Laboratory for Ultrafine Materials of Ministry of Education, The State Key Laboratory of Bioreactor Engineering, and Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology , Shanghai 200237, People's Republic of China
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5
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Fully atomistic molecular dynamics simulation of nanosilica-filled crosslinked polybutadiene. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.04.061] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Prodinger S, Derewinski MA, Vjunov A, Burton SD, Arslan I, Lercher JA. Improving Stability of Zeolites in Aqueous Phase via Selective Removal of Structural Defects. J Am Chem Soc 2016; 138:4408-15. [DOI: 10.1021/jacs.5b12785] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sebastian Prodinger
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Miroslaw A. Derewinski
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Aleksei Vjunov
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Sarah D. Burton
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Ilke Arslan
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
| | - Johannes A. Lercher
- Institute for Integrated
Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, United States
- Department of Chemistry and Catalysis Research
Institute, TU München, Lichtenbergstrasse 4, 85748 Garching, Germany
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Parameters optimization of recombinant hepatitis B antigen adsorption–desorption in purification process on three different kinds of diatomaceous earth matrix. Chem Eng Res Des 2014. [DOI: 10.1016/j.cherd.2014.03.015] [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]
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8
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Identification and Characterization of Surface Hydroxyl Groups by Infrared Spectroscopy. ADVANCES IN CATALYSIS 2014. [DOI: 10.1016/b978-0-12-800127-1.00002-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Rimola A, Costa D, Sodupe M, Lambert JF, Ugliengo P. Silica surface features and their role in the adsorption of biomolecules: computational modeling and experiments. Chem Rev 2013; 113:4216-313. [PMID: 23289428 DOI: 10.1021/cr3003054] [Citation(s) in RCA: 323] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Albert Rimola
- Departament de Química, Universitat Autònoma de Barcelona, 08193 Bellaterra (Cerdanyola del Vallès), Spain
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Wang Y, Wang F, Song Q, Xin Q, Xu S, Xu J. Heterogeneous Ceria Catalyst with Water-Tolerant Lewis Acidic Sites for One-Pot Synthesis of 1,3-Diols via Prins Condensation and Hydrolysis Reactions. J Am Chem Soc 2013; 135:1506-15. [DOI: 10.1021/ja310498c] [Citation(s) in RCA: 179] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Yehong Wang
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Feng Wang
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Qi Song
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Qin Xin
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Shutao Xu
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Jie Xu
- State Key Laboratory of Catalysis, Dalian
National
Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
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Wisser FM, Abele M, Gasthauer M, Müller K, Moszner N, Kickelbick G. Detection of surface silanol groups on pristine and functionalized silica mixed oxides and zirconia. J Colloid Interface Sci 2012; 374:77-82. [PMID: 22342222 DOI: 10.1016/j.jcis.2012.01.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 12/16/2011] [Accepted: 01/08/2012] [Indexed: 11/16/2022]
Abstract
The surface hydroxyl content and surface structure of silica and other oxides with and without surface modification were systematically studied by solid state (29)Si NMR, thermogravimetric analysis, and the lithium alanate method. Aerosil 90 as a well described reference system and functionalized zirconia-silica particles were used in the validation of the lithium alanate method. 3-Methacryloxypropyltrimethoxysilane and dodecylphosphonic acid were applied as surface modifiers. The determination of silanol content of Aerosil 90 by (29)Si NMR and TGA confirms the results obtained by the lithium alanate method, which also allows for the determination of the remaining surface hydroxyl content after surface modification. For both silane coupling agents, the residual hydroxyl content of modified zirconia-silica is decreased by a factor of approximately 2 compared with that of the unmodified mixed oxide, whereas after modification with dodecylphosphonic acid, the hydroxyl content is slightly higher. These results are again in good agreement with those by (29)Si NMR confirming that the lithium alanate method is a reliable and easily practicable method for surface hydroxyl determination.
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Affiliation(s)
- Florian M Wisser
- Saarland University, Inorganic Solid State Chemistry, Am Markt Zeile 3, D-66125 Saarbrücken, Germany
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Pervaporation of organic/water mixtures with hydrophobic silica membranes functionalized by phenyl groups. J Memb Sci 2011. [DOI: 10.1016/j.memsci.2011.06.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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A fascinating Suzuki homo-coupling reaction over anchored gold Schiff base complexes on mesoporous host. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.molcata.2011.04.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Veera Dandu PR, Penta NK, Peethala BC, Babu SV. Novel phosphate-functionalized silica-based dispersions for selectively polishing silicon nitride over silicon dioxide and polysilicon films. J Colloid Interface Sci 2010; 348:114-8. [PMID: 20471025 DOI: 10.1016/j.jcis.2010.04.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 04/14/2010] [Accepted: 04/15/2010] [Indexed: 11/17/2022]
Abstract
We prepared and characterized novel phosphate-functionalized silica particles, and showed that, by using them during chemical mechanical polishing, both silicon dioxide and polysilicon removal rates can be suppressed while simultaneously enhancing silicon nitride removal rates. We achieved a silicon nitride:silicon dioxide:polysilicon removal rate selectivity of (>20):1:1. The measured removal rates of silicon dioxide, silicon nitride, and polysilicon are related to the electrostatic interactions and chemical reactivity between these films and the modified-silica abrasives.
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Affiliation(s)
- P R Veera Dandu
- Department of Chemical and Biomolecular Engineering and Center for Advanced Materials Processing, Clarkson University, Potsdam, NY 13676, USA
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Czaun M, Hevesi L, Takafuji M, Ihara H. Novel Surface-Attachable Multifunctional Initiators: Synthesis, Grafting, and Polymerization in Aprotic and Protic Solvents. Macromolecules 2009. [DOI: 10.1021/ma900419q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Miklós Czaun
- Laboratoire de Chimie des Matériaux Organiques, Facultés Universitaires Notre-Dame de la Paix, 61 Rue de Bruxelles, Namur 5000, Belgium
- Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
| | - László Hevesi
- Laboratoire de Chimie des Matériaux Organiques, Facultés Universitaires Notre-Dame de la Paix, 61 Rue de Bruxelles, Namur 5000, Belgium
| | - Makoto Takafuji
- Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
| | - Hirotaka Ihara
- Department of Applied Chemistry and Biochemistry, Faculty of Engineering, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
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Chen ZM, Jie CY, Li S, Wang HL, Wang CX, Xu JR, Hua W. Heterogeneous reactions of methacrolein and methyl vinyl ketone: Kinetics and mechanisms of uptake and ozonolysis on silicon dioxide. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009754] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Atmospheric heterogeneous reaction of acetone: Adsorption and desorption kinetics and mechanisms on SiO2 particles. Sci Bull (Beijing) 2008. [DOI: 10.1007/s11434-007-0489-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lercher JA, Jentys A. Infrared and Raman Spectroscopy for Characterizing Zeolites. STUDIES IN SURFACE SCIENCE AND CATALYSIS 2007. [DOI: 10.1016/s0167-2991(07)80801-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Berrier E, Zoller C, Beclin F, Turrell S, Bouazaoui M, Capoen B. Microstructures and Structural Properties of Sol−Gel Silica Foams. J Phys Chem B 2005; 109:22799-807. [PMID: 16853970 DOI: 10.1021/jp053089+] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Silica xerogels were synthesized and annealed at 1000 degrees C for different durations to yield stable silica materials. The samples were prepared through base-catalyzed hydrolysis and condensation of tetramethyl orthosilicate in methanol. After aging and drying steps, clear and solid xerogels exhibiting a narrow pore size distribution were achieved. The annealing treatment of these xerogels was performed at 1000 degrees C and proved in the present study to lead to a monolithic glass when a progressive heat-treatment procedure was employed to attain 1000 degrees C. In addition to the expected glass, silica foams and ordered phases were observed when the samples were instantaneously heat-treated at 1000 degrees C. Raman spectra of the foamed materials exhibit the classical features of amorphous silica, whereas transmission electronic microscopy pictures reveal the presence of crystallized domains within the vitreous matrix. These crystallites are prone to nucleation and growth processes, which jeopardize the believed stability of the silica foam. The assessment of the hydroxyl content by IR spectroscopy reveals the role played by the latter polycondensation of silanols. The occurrence of foaming process was thus found to result from two competitive phenomena occurring at 1000 degrees C: evacuation of water-related species and viscous sintering.
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Affiliation(s)
- Elise Berrier
- Laboratoire PhLAM (CNRS, UMR 8523), Université des Sciences et Technologies de Lille, Villeneuve d'Ascq F-59655, France
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Haider MM, Hartinger I, Göschl K, Demmelmair A. Quantitative determination of silanol in quartz applying diffuse reflectance infrared fourier transform and chemometrics. APPLIED SPECTROSCOPY 2004; 58:679-682. [PMID: 18171511 DOI: 10.1366/000370204872935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The silanol concentration of quartz was determined by mixing 50 mg ground silica sample with 500 mg KBr followed by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and chemometric data analysis. Reference samples were prepared by blending ground quartz of different silanol content. Good correlation was achieved between 10 and 240 ppm Si-OH by mass. The chemometric model's quality is characterized by a correlation coefficient of 0.965 (cross-validation) using five latent variables (factors) and a root mean square error of calibration (RMSEC) of 7 ppm. Chemometric data is compared to results from univariate data analysis. The biggest impact on the reproducibility is due to sample preparation (grinding and blending), which is dependant on the operator involved.
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Affiliation(s)
- Markus M Haider
- Zentrale Analytik, Wacker Chemie, Johannes Hess Str. 24, Burghausen D84480, Germany
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22
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Huang HY, Yang RT, Chinn D, Munson CL. Amine-Grafted MCM-48 and Silica Xerogel as Superior Sorbents for Acidic Gas Removal from Natural Gas. Ind Eng Chem Res 2002. [DOI: 10.1021/ie020440u] [Citation(s) in RCA: 581] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Dijkstra TW, Duchateau R, Van Santen RA, Meetsma A, Yap GPA. Silsesquioxane models for geminal silica surface silanol sites. A spectroscopic investigation of different types of silanols. J Am Chem Soc 2002; 124:9856-64. [PMID: 12175245 DOI: 10.1021/ja0122243] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The incompletely condensed monosilylated silsesquioxanes (c-C5H9)7Si7O9(OSiRR'2)(OH)2 (SiRR'2 = SiMe3, SiMe2C(H)CH2, SiMePh2) were reacted with SiCl(4) in the presence of an amine which yielded the dichloro compounds (c-C5H9)7Si7O9(OSiRR'2)O2SiCl2 (1-3). These compounds could be hydrolyzed into the corresponding silsesquioxanes containing geminal silanols, (c-C5H9)7Si7O9(OSiRR'2)O2Si(OH)2 (4-6). At elevated temperatures, the geminal silsesquioxanes 4 and 5 undergo condensation reactions and form the closed-cage silsesquioxane monosilanol, (c-C5H9)7Si8O12(OH). The more sterically hindered geminal silsesquioxane 6 undergoes in solution intermolecular dehydroxylation, yielding the thermodynamically stable dimeric disilanol, [(c-C5H9)7Si7O9(OSiMePh2)(O2Si(OH)-)]2-(mu-O) (7). NMR and FT-IR studies show that the two silanols of the geminal silsesquioxanes 4-6 are different from each other with respect to hydrogen bonding, both in solution and in the solid state. Hydrogen bonding of the geminal silanol-containing silsesquioxanes was examined and compared to hydrogen bonding in silsesquioxanes possessing vicinal or isolated silanol groups. The relative Brønsted acidity of the geminal silanols was determined using pK(ip) (ion-pair acidity) measurements in THF with UV-vis. These acidities were compared with those of other silsesquioxanes containing silanol groups. Acidities of 4-6 were found to be among the lowest known for silsesquioxanes.
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Affiliation(s)
- Tessa W Dijkstra
- Schuit Institute of Catalysis and Department of Polymer Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
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Watson RB, Ozkan US. Spectroscopic and Structural Characterization of Low-Level Alkali Doping Effects on Mo/Silica−Titania Catalysts. J Phys Chem B 2002. [DOI: 10.1021/jp025512+] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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The effect of the nature and the state of the surface of highly dispersed silicon, aluminum, and titanium oxides on their sorption characteristics. THEOR EXP CHEM+ 2000. [DOI: 10.1007/bf02511532] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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