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David J.w. Grant - One of the best experts on this subject based on the ideXlab platform.
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Computing the Relative Nucleation Rate of Phenylbutazone and Sulfamerazine in Various Solvents
Crystal Growth & Design, 2005Co-Authors: Sharmistha Datta, David J.w. GrantAbstract:This work simulates the nucleation of Sulfamerazine in acetone, methanol, or water, and phenylbutazone in diethyl ether, methanol, or acetone. A new method is developed to estimate the time of onse...
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Crystallization and Transitions of Sulfamerazine Polymorphs
Journal of pharmaceutical sciences, 2002Co-Authors: Geoff G. Z. Zhang, Mark T. Zell, R. Todd Burkhardt, Eric J. Munson, David J.w. GrantAbstract:A bulk powder of Sulfamerazine polymorph II in a narrow distribution of particle size was prepared for the first time. The two known Sulfamerazine polymorphs, I and II, were physically characterized by optical microscopy, powder X-ray diffractometry, differential scanning calorimetry, carbon-13 solid-state nuclear magnetic resonance spectroscopy, and measurements of aqueous solubility and density. The thermodynamics and kinetics of the transition between the polymorphs was examined under various pharmaceutically relevant conditions, such as heating, cooling, milling, compaction, and contact with solvents. The two polymorphs were found to be enantiotropes with slow kinetics of interconversion. The thermodynamic transition temperature lies between 51 and 54°C, with polymorph II stable at lower temperatures. Ostwald's Rule of Stages explains the crystallization of the polymorphs from various solvents and may account for the delay in the discovery of polymorph II. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:1089–1100, 2002
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polymorph screening influence of solvents on the rate of solvent mediated polymorphic transformation
Journal of Pharmaceutical Sciences, 2001Co-Authors: Victor G Young, David J.w. GrantAbstract:Solvent-mediated polymorphic transformation is an efficient technique to obtain the most stable polymorph. The rate of solvent-mediated polymorphic transformation of Sulfamerazine at 24°C in various solvents and solvent mixtures is controlled by the nucleation rate of the more stable Form II. The transformation rate is generally higher in the solvent giving a higher solubility and is low in the solvent giving a low solubility (8 mmol/L). In these solvents, because of a high interfacial energy, the metastable zone may be wider than the solubility difference between two polymorphs, such that the critical free energy barrier for nucleation cannot be overcome. In addition to the solubility, the strength of the solvent-solute interactions is also important in determining the transformation rate. For Sulfamerazine, the transformation rate is lower in the solvent with a stronger hydrogen bond acceptor propensity. Because solubility is higher in the solvent with stronger hydrogen bond acceptor propensity, the balance of solubility and strength of hydrogen bonding interactions between the solute and solvent molecules determines the polymorphic transformation rate. Degree of agitation and temperature also change the polymorphic transformation rate by influencing the crystallization kinetics of the more stable polymorph. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:1878–1890, 2001
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Influence of Crystal Structure on the Tableting Properties of Sulfamerazine Polymorphs
Pharmaceutical Research, 2001Co-Authors: Changquan Sun, David J.w. GrantAbstract:Purpose . To understand the influence of polymorphic structure on the tableting properties of Sulfamerazine. Methods . Bulk powders of Sulfamerazine polymorph I and of two batches, II(A) and II(B) of different particle size, of polymorph II were crystallized. The powders were compressed to form tablets whose porosity and tensile strength were measured. The relationships between tensile strength, porosity and compaction pressure were analyzed by the method developed by Joiris, E., et al. Pharm. Res. 15 :1122-1130 (1998). Results . The sensitivity of tensile strength to compaction pressure, known as the tabletability, follows the order, I >> II(A) > II(B) and the porosity at the same compaction pressure, which measures the compressibility, follows the order, I
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Influence of crystal structure on the tableting properties of Sulfamerazine polymorphs.
Pharmaceutical research, 2001Co-Authors: Changquan Calvin Sun, David J.w. GrantAbstract:Purpose. To understand the influence of polymorphic structure on the tableting properties of Sulfamerazine.
Lenuta Profire - One of the best experts on this subject based on the ideXlab platform.
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Article Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
2016Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:Abstract: The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190 % and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan relate
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Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
International journal of molecular sciences, 2015Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190% and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan related to DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability. This compound showed also a good ferric reducing power and improved total antioxidant capacity.
G Golzar M Hossain - One of the best experts on this subject based on the ideXlab platform.
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Sulfamerazine tetra hydro furan monosolvate
IUCrData, 2016Co-Authors: G Golzar M HossainAbstract:The title solvate, C11H12N4O2S·C4H8O, crystallizes with three molecules of Sulfamerazine [4-amino-N-(4-methylpyrimidin-2-yl)benzenesulfonamide] and three molecules of tetrahydrofuran solvent in the asymmetric unit. The dihedral angles between the aromatic rings in the Sulfamerazine molecules are 83.40 (12), 87.40 (12) and 89.54 (12)°. In the crystal, molecules are linked by N—H⋯O and N—H⋯N hydrogen bonds, generating (10-6) sheets.
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syntheses and characterisation of mercury complexes of sulfadiazine Sulfamerazine and sulfamethazine
Polyhedron, 2007Co-Authors: G Golzar M Hossain, Angelo James Amoroso, Afroza Banu, K M A MalikAbstract:Abstract The triple sulfa drugs, sulfadiazine, Sulfamerazine and sulfamethazine, form a large number of metal complexes in different solvent media. The present studies show the synthesis and characterization of the Hg(II) complexes of sulfadiazine 1, Sulfamerazine 2 and sulfamethazine 3 in dimethylformamide solution in presence of ammonia. The compounds were characterised by spectroscopic methods and crystal structures of the complexes were determined. All the compounds, 1, 2 and 3, crystallise in monoclinic crystal systems with the space groups of C2/c, C2/c and P21/c, respectively. Compounds 1 and 3 have eight coordinate ‘2+6’ geometries, with two tridentate sulfonamide ions and two DMF molecules in the coordination sphere. Complex 2 has a six co-ordinate, ‘2+4’ geometry which contains a short linear N–Hg–N moiety from co-ordinated sulfonamides. The IR spectral data suggest the binding of mercury atom to the sulfonamidic nitrogen atoms in agreement with the crystal structure determination.
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a new polymorph of Sulfamerazine
Acta Crystallographica Section E-structure Reports Online, 2006Co-Authors: G Golzar M HossainAbstract:In the title compound, C11H12N4O2S, molecules are linked by intermolecular N—H⋯N and O—H⋯O hydrogen bonds, forming a hydrogen-bonded network.
Oana Maria Dragostin - One of the best experts on this subject based on the ideXlab platform.
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Article Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
2016Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:Abstract: The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190 % and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan relate
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Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
International journal of molecular sciences, 2015Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190% and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan related to DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability. This compound showed also a good ferric reducing power and improved total antioxidant capacity.
Sangram Keshari Samal - One of the best experts on this subject based on the ideXlab platform.
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Article Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
2016Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:Abstract: The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190 % and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan relate
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Development and Characterization of Novel Films Based on Sulfonamide-Chitosan Derivatives for Potential Wound Dressing
International journal of molecular sciences, 2015Co-Authors: Oana Maria Dragostin, Sangram Keshari Samal, Florentina Lupascu, Andreea Pânzariu, Peter Dubruel, Dan Lupascu, Cristina Tuchilus, Cornelia Vasile, Lenuta ProfireAbstract:The objective of this study was to develop new films based on chitosan functionalized with sulfonamide drugs (sulfametoxydiazine, sulfadiazine, sulfadimetho-xine, sulfamethoxazol, Sulfamerazine, sulfizoxazol) in order to enhance the biological effects of chitosan. The morphology and physical properties of functionalized chitosan films as well the antioxidant effects of sulfonamide-chitosan derivatives were investigated. The chitosan-derivative films showed a rough surface and hydrophilic properties, which are very important features for their use as a wound dressing. The film based on chitosan-sulfisoxazol (CS-S6) showed the highest swelling ratio (197%) and the highest biodegradation rate (63.04%) in comparison to chitosan film for which the swelling ratio was 190% and biodegradation rate was only 10%. Referring to the antioxidant effects the most active was chitosan-Sulfamerazine (CS-S5) which was 8.3 times more active than chitosan related to DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability. This compound showed also a good ferric reducing power and improved total antioxidant capacity.
