The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Stephen Edge - One of the best experts on this subject based on the ideXlab platform.
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Directional bonding in compacted Microcrystalline Cellulose.
Drug Development and Industrial Pharmacy, 2020Co-Authors: Stephen Edge, D. Fraser Steele, Mike Tobyn, John N. Staniforth, Ansong ChenAbstract:The mechanical properties of compacts of Microcrystalline Cellulose (MCC) and silicified Microcrystalline Cellulose (SMCC) were evaluated by tensile testing, diametric compression testing, and compression testing. For tensile and compression testing, cubic specimens were carefully machined from MCC and SMCC compacts, and the tensile and compression strengths were evaluated both normal and parallel to the compaction direction. The cubic tensile strengths were compared to values obtained from the diametric compression test. The results obtained using the diametric compression test suggested compacts of SMCC exhibit greater strength than those of MCC. In addition, the cubes machined from compacts of MCC and SMCC exhibited directional strength; the direction normal to the compaction direction displayed the greater tensile strength; and the parallel direction had greater compression strength. The diametric compression test afforded strength values with reduced spread compared to the values collected from the c...
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Surface Energy of Microcrystalline Cellulose Determined by Capillary Intrusion and Inverse Gas Chromatography
Aaps Journal, 2008Co-Authors: D. Fraser Steele, Mike Tobyn, John N. Staniforth, R. Christian Moreton, Paul M. Young, Stephen EdgeAbstract:Surface energy data for samples of Microcrystalline Cellulose have been obtained using two techniques: capillary intrusion and inverse gas chromatography. Ten Microcrystalline Cellulose materials, studied using capillary intrusion, showed significant differences in the measured surface energetics (in terms of total surface energy and the acid–base characteristics of the Cellulose surface), with variations noted between the seven different manufacturers who produced the Microcrystalline Cellulose samples. The surface energy data from capillary intrusion was similar to data obtained using inverse gas chromatography with the column maintained at 44% relative humidity for the three samples of Microcrystalline Cellulose studied. This suggests that capillary intrusion may be a suitable method to study the surface energy of pharmaceutical samples.
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Physicochemical and Mechanical Evaluation of a Novel High Density Grade of Silicified Microcrystalline Cellulose
Drug Development and Industrial Pharmacy, 2004Co-Authors: D. Fraser Steele, Stephen Edge, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:High density Microcrystalline Cellulose (MCC) is a relatively free flowing grade of MCC that finds use in direct compression tableting and hard gelatin capsule filling applications. Silicified high density Microcrystalline Cellulose has recently been introduced. This material has been compared to other grades of MCC and previously silicified Microcrystalline Cellulose (SMCC). The results suggest that, as observed for other grades of SMCC, the material exhibits no detectable chemical or polymorphic differences to standard material, some improvement in flow characteristics, but shows considerably enhanced mechanical properties.
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Adsorption of an Amine Drug onto Microcrystalline Cellulose and Silicified Microcrystalline Cellulose Samples
Drug Development and Industrial Pharmacy, 2003Co-Authors: D. Fraser Steele, Stephen Edge, Mike Tobyn, R. Christian Moreton, John N. StaniforthAbstract:The adsorption of a model amine drug (tacrine hydrochloride) from aqueous solution onto 21 Microcrystalline Cellulose (MCC) based samples has been investigated. The MCC source (manufacturer) affected adsorption. The adsorption appeared to be fully reversible. Adsorption was reduced by the use of high-density grade MCC, high-energy milling, and silicification. Adsorption of the model drug was not affected by the particle size of the MCC. Significant variations of the adsorption characteristics between batches of certain MCC products were found. The primary mode of adsorption was by ion exchange.
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The mechanical properties of compacts of Microcrystalline Cellulose and silicified Microcrystalline Cellulose
International Journal of Pharmaceutics, 2000Co-Authors: Stephen Edge, D. Fraser Steele, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:The mechanical properties of compacts of unlubricated Microcrystalline Cellulose and silicified Microcrystalline Cellulose were evaluated using the diametric tensile test. The results suggested that, under comparable testing conditions, compacts of silicified Microcrystalline Cellulose exhibited greater strength than those of Microcrystalline Cellulose. In addition to enhanced strength, silicified Microcrystalline Cellulose compacts exhibited greater stiffness and required considerably more energy for tensile failure to occur. Comparison of the data with that obtained for a dry blend of silicon dioxide/Microcrystalline Cellulose suggested that the functionality benefits of silicification were not due to a simple composite material model.
John N. Staniforth - One of the best experts on this subject based on the ideXlab platform.
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Directional bonding in compacted Microcrystalline Cellulose.
Drug Development and Industrial Pharmacy, 2020Co-Authors: Stephen Edge, D. Fraser Steele, Mike Tobyn, John N. Staniforth, Ansong ChenAbstract:The mechanical properties of compacts of Microcrystalline Cellulose (MCC) and silicified Microcrystalline Cellulose (SMCC) were evaluated by tensile testing, diametric compression testing, and compression testing. For tensile and compression testing, cubic specimens were carefully machined from MCC and SMCC compacts, and the tensile and compression strengths were evaluated both normal and parallel to the compaction direction. The cubic tensile strengths were compared to values obtained from the diametric compression test. The results obtained using the diametric compression test suggested compacts of SMCC exhibit greater strength than those of MCC. In addition, the cubes machined from compacts of MCC and SMCC exhibited directional strength; the direction normal to the compaction direction displayed the greater tensile strength; and the parallel direction had greater compression strength. The diametric compression test afforded strength values with reduced spread compared to the values collected from the c...
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Surface Energy of Microcrystalline Cellulose Determined by Capillary Intrusion and Inverse Gas Chromatography
Aaps Journal, 2008Co-Authors: D. Fraser Steele, Mike Tobyn, John N. Staniforth, R. Christian Moreton, Paul M. Young, Stephen EdgeAbstract:Surface energy data for samples of Microcrystalline Cellulose have been obtained using two techniques: capillary intrusion and inverse gas chromatography. Ten Microcrystalline Cellulose materials, studied using capillary intrusion, showed significant differences in the measured surface energetics (in terms of total surface energy and the acid–base characteristics of the Cellulose surface), with variations noted between the seven different manufacturers who produced the Microcrystalline Cellulose samples. The surface energy data from capillary intrusion was similar to data obtained using inverse gas chromatography with the column maintained at 44% relative humidity for the three samples of Microcrystalline Cellulose studied. This suggests that capillary intrusion may be a suitable method to study the surface energy of pharmaceutical samples.
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Physicochemical and Mechanical Evaluation of a Novel High Density Grade of Silicified Microcrystalline Cellulose
Drug Development and Industrial Pharmacy, 2004Co-Authors: D. Fraser Steele, Stephen Edge, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:High density Microcrystalline Cellulose (MCC) is a relatively free flowing grade of MCC that finds use in direct compression tableting and hard gelatin capsule filling applications. Silicified high density Microcrystalline Cellulose has recently been introduced. This material has been compared to other grades of MCC and previously silicified Microcrystalline Cellulose (SMCC). The results suggest that, as observed for other grades of SMCC, the material exhibits no detectable chemical or polymorphic differences to standard material, some improvement in flow characteristics, but shows considerably enhanced mechanical properties.
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Adsorption of an Amine Drug onto Microcrystalline Cellulose and Silicified Microcrystalline Cellulose Samples
Drug Development and Industrial Pharmacy, 2003Co-Authors: D. Fraser Steele, Stephen Edge, Mike Tobyn, R. Christian Moreton, John N. StaniforthAbstract:The adsorption of a model amine drug (tacrine hydrochloride) from aqueous solution onto 21 Microcrystalline Cellulose (MCC) based samples has been investigated. The MCC source (manufacturer) affected adsorption. The adsorption appeared to be fully reversible. Adsorption was reduced by the use of high-density grade MCC, high-energy milling, and silicification. Adsorption of the model drug was not affected by the particle size of the MCC. Significant variations of the adsorption characteristics between batches of certain MCC products were found. The primary mode of adsorption was by ion exchange.
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The mechanical properties of compacts of Microcrystalline Cellulose and silicified Microcrystalline Cellulose
International Journal of Pharmaceutics, 2000Co-Authors: Stephen Edge, D. Fraser Steele, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:The mechanical properties of compacts of unlubricated Microcrystalline Cellulose and silicified Microcrystalline Cellulose were evaluated using the diametric tensile test. The results suggested that, under comparable testing conditions, compacts of silicified Microcrystalline Cellulose exhibited greater strength than those of Microcrystalline Cellulose. In addition to enhanced strength, silicified Microcrystalline Cellulose compacts exhibited greater stiffness and required considerably more energy for tensile failure to occur. Comparison of the data with that obtained for a dry blend of silicon dioxide/Microcrystalline Cellulose suggested that the functionality benefits of silicification were not due to a simple composite material model.
Mike Tobyn - One of the best experts on this subject based on the ideXlab platform.
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Directional bonding in compacted Microcrystalline Cellulose.
Drug Development and Industrial Pharmacy, 2020Co-Authors: Stephen Edge, D. Fraser Steele, Mike Tobyn, John N. Staniforth, Ansong ChenAbstract:The mechanical properties of compacts of Microcrystalline Cellulose (MCC) and silicified Microcrystalline Cellulose (SMCC) were evaluated by tensile testing, diametric compression testing, and compression testing. For tensile and compression testing, cubic specimens were carefully machined from MCC and SMCC compacts, and the tensile and compression strengths were evaluated both normal and parallel to the compaction direction. The cubic tensile strengths were compared to values obtained from the diametric compression test. The results obtained using the diametric compression test suggested compacts of SMCC exhibit greater strength than those of MCC. In addition, the cubes machined from compacts of MCC and SMCC exhibited directional strength; the direction normal to the compaction direction displayed the greater tensile strength; and the parallel direction had greater compression strength. The diametric compression test afforded strength values with reduced spread compared to the values collected from the c...
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Surface Energy of Microcrystalline Cellulose Determined by Capillary Intrusion and Inverse Gas Chromatography
Aaps Journal, 2008Co-Authors: D. Fraser Steele, Mike Tobyn, John N. Staniforth, R. Christian Moreton, Paul M. Young, Stephen EdgeAbstract:Surface energy data for samples of Microcrystalline Cellulose have been obtained using two techniques: capillary intrusion and inverse gas chromatography. Ten Microcrystalline Cellulose materials, studied using capillary intrusion, showed significant differences in the measured surface energetics (in terms of total surface energy and the acid–base characteristics of the Cellulose surface), with variations noted between the seven different manufacturers who produced the Microcrystalline Cellulose samples. The surface energy data from capillary intrusion was similar to data obtained using inverse gas chromatography with the column maintained at 44% relative humidity for the three samples of Microcrystalline Cellulose studied. This suggests that capillary intrusion may be a suitable method to study the surface energy of pharmaceutical samples.
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Physicochemical and Mechanical Evaluation of a Novel High Density Grade of Silicified Microcrystalline Cellulose
Drug Development and Industrial Pharmacy, 2004Co-Authors: D. Fraser Steele, Stephen Edge, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:High density Microcrystalline Cellulose (MCC) is a relatively free flowing grade of MCC that finds use in direct compression tableting and hard gelatin capsule filling applications. Silicified high density Microcrystalline Cellulose has recently been introduced. This material has been compared to other grades of MCC and previously silicified Microcrystalline Cellulose (SMCC). The results suggest that, as observed for other grades of SMCC, the material exhibits no detectable chemical or polymorphic differences to standard material, some improvement in flow characteristics, but shows considerably enhanced mechanical properties.
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Adsorption of an Amine Drug onto Microcrystalline Cellulose and Silicified Microcrystalline Cellulose Samples
Drug Development and Industrial Pharmacy, 2003Co-Authors: D. Fraser Steele, Stephen Edge, Mike Tobyn, R. Christian Moreton, John N. StaniforthAbstract:The adsorption of a model amine drug (tacrine hydrochloride) from aqueous solution onto 21 Microcrystalline Cellulose (MCC) based samples has been investigated. The MCC source (manufacturer) affected adsorption. The adsorption appeared to be fully reversible. Adsorption was reduced by the use of high-density grade MCC, high-energy milling, and silicification. Adsorption of the model drug was not affected by the particle size of the MCC. Significant variations of the adsorption characteristics between batches of certain MCC products were found. The primary mode of adsorption was by ion exchange.
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The mechanical properties of compacts of Microcrystalline Cellulose and silicified Microcrystalline Cellulose
International Journal of Pharmaceutics, 2000Co-Authors: Stephen Edge, D. Fraser Steele, Ansong Chen, Mike Tobyn, John N. StaniforthAbstract:The mechanical properties of compacts of unlubricated Microcrystalline Cellulose and silicified Microcrystalline Cellulose were evaluated using the diametric tensile test. The results suggested that, under comparable testing conditions, compacts of silicified Microcrystalline Cellulose exhibited greater strength than those of Microcrystalline Cellulose. In addition to enhanced strength, silicified Microcrystalline Cellulose compacts exhibited greater stiffness and required considerably more energy for tensile failure to occur. Comparison of the data with that obtained for a dry blend of silicon dioxide/Microcrystalline Cellulose suggested that the functionality benefits of silicification were not due to a simple composite material model.
Mohammad L Hassan - One of the best experts on this subject based on the ideXlab platform.
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physical and mechanical properties of Microcrystalline Cellulose prepared from agricultural residues
Carbohydrate Polymers, 2007Co-Authors: Mohamed Elsakhawy, Mohammad L HassanAbstract:Microcrystalline Cellulose (MCC) was prepared from local agricultural residues, namely, bagasse, rice straw, and cotton stalks bleached pulps. Hydrolysis of bleached pulps was carried out using hydrochloric or sulfuric acid to study the effect of the acid used on the properties of the produced Microcrystalline Cellulose such as degree of polymerization (DP), crystallinity index (CrI), crystallite size, bulk density, particle size, and thermal stability. The mechanical properties of tablets made from Microcrystalline Cellulose of different agricultural residues were tested and compared to a commercial-grade MCC. The use of rice straw pulp in different proportions as a source of silica to prepare silicified Microcrystalline Cellulose (SMCC) was investigated. The effect of the percent of rice straw added on the mechanical properties of tablets before and after wet granulation was studied.
Waleed K. El-zawawy - One of the best experts on this subject based on the ideXlab platform.
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Coupled acid and enzyme mediated production of Microcrystalline Cellulose from corn cob and cotton gin waste
Cellulose, 2007Co-Authors: Foster A. Agblevor, Maha M. Ibrahim, Waleed K. El-zawawyAbstract:Microcrystalline Cellulose has applications in food, pharmaceuticals, and other industries. Most Microcrystalline Cellulose (MCC) is produced from dissolving pulp using concentrated acids. We investigated steam explosion treatment of corn cobs and cotton gin waste for the production of Microcrystalline Cellulose. The corn cob was converted into a coarse brown powder after steam explosion and the lignin and residual hemiCellulose fractions were extracted respectively with sodium hydroxide solution and water. The residual Cellulose was readily bleached with hydrogen peroxide and converted to Microcrystalline Cellulose using hydrochloric acid, sulfuric acid and cellulase enzyme preparation. The resulting Microcrystalline Cellulose samples had properties that were similar to commercial Microcrystalline Cellulose. Similarly, cotton gin waste was steam exploded and converted into Microcrystalline Cellulose, but this material was more difficult to bleach using hydrogen peroxide. The degree of polymerization for the MCC samples ranged from 188.6 to 549.8 compared to 427.4 for Avicel PH101 MCC. © Springer Science+Business Media, Inc. 2007.
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Coupled acid and enzyme mediated production of Microcrystalline Cellulose from corn cob and cotton gin waste
Cellulose, 2006Co-Authors: Foster A. Agblevor, Maha M. Ibrahim, Waleed K. El-zawawyAbstract:Microcrystalline Cellulose has applications in food, pharmaceuticals, and other industries. Most Microcrystalline Cellulose (MCC) is produced from dissolving pulp using concentrated acids. We investigated steam explosion treatment of corn cobs and cotton gin waste for the production of Microcrystalline Cellulose. The corn cob was converted into a coarse brown powder after steam explosion and the lignin and residual hemiCellulose fractions were extracted respectively with sodium hydroxide solution and water. The residual Cellulose was readily bleached with hydrogen peroxide and converted to Microcrystalline Cellulose using hydrochloric acid, sulfuric acid and cellulase enzyme preparation. The resulting Microcrystalline Cellulose samples had properties that were similar to commercial Microcrystalline Cellulose. Similarly, cotton gin waste was steam exploded and converted into Microcrystalline Cellulose, but this material was more difficult to bleach using hydrogen peroxide. The degree of polymerization for the MCC samples ranged from 188.6 to 549.8 compared to 427.4 for Avicel PH101 MCC.
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Enzyme and acid mediated production of Microcrystalline Cellulose from agricultural wastes
AIChE Annual Meeting, Conference Proceedings, 2005Co-Authors: Foster A. Agblevor, Waleed K. El-zawawyAbstract:Microcrystalline Cellulose has a wide application in food, pharmaceuticals, and other industries. Most Microcrystalline Cellulose is produced from dissolving pulps using concentrated acids. We investigated steam explosion treatment of corn cobs and cotton gin waste for the production of Microcrystalline Cellulose. Steam explosion conditions varied from severities of 2.8 to 5.0. The corn cob was converted into a fine powder after steam explosion and the hemiCellulose fraction was easily extracted with water and the lignolytic fraction was extracted with sodium hydroxide solution. The residual Cellulose was first bleached with hydrogen peroxide and then converted into Microcrystalline Cellulose using hydrochloric acid, sulfuric acid and cellulase enzyme preparation. The resulting Microcrystalline Cellulose samples had properties that were comparable to commercial Microcrystalline Cellulose. Similarly, cotton gin was steam exploded and converted into Microcrystalline Cellulose. However, the cotton gin waste was more difficult to steam treat and the product was not readily bleached. Whereas the Microcrystalline Cellulose from the cotton gin waste appeared like fiber strands, those from the corn cob were particles when analyzed with scanning electron microscope.