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Anne Marie Healy - One of the best experts on this subject based on the ideXlab platform.
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modelling and shadowgraph imaging of cocrystal dissolution and assessment of in vitro antimicrobial activity for Sulfadimidine 4 aminosalicylic acid cocrystals
European Journal of Pharmaceutical Sciences, 2016Co-Authors: Dolores R. Serrano, Carolina Galiana, Tim Persoons, Deirdre M Darcy, Maria Auxiliadora Deaayuela, Anne Marie HealyAbstract:Abstract Purpose The aim of this work was to evaluate the influence of crystal habit on the dissolution and in vitro antibacterial and anitiprotozoal activity of Sulfadimidine:4-aminosalicylic acid cocrystals. Methods Cocrystals were produced via milling or solvent mediated processes. In vitro dissolution was carried out in the flow-through apparatus, with shadowgraph imaging and mechanistic mathematical models used to observe and simulate particle dissolution. In vitro activity was tested using agar diffusion assays. Results Cocrystallisation via milling produced small polyhedral crystals with antimicrobial activity significantly higher than Sulfadimidine alone, consistent with a fast dissolution rate which was matched only by cocrystals which were milled following solvent evaporation. Cocrystallisation by solvent evaporation (ethanol, acetone) or spray drying produced flattened, plate-like or quasi-spherical cocrystals, respectively, with more hydrophobic surfaces and greater tendency to form aggregates in aqueous media, limiting both the dissolution rate and in vitro activity. Deviation from predicted dissolution profiles was attributable to aggregation behaviour, supported by observations from shadowgraph imaging. Conclusions Aggregation behaviour during dissolution of cocrystals with different habits affected the dissolution rate, consistent with in vitro activity. Combining mechanistic models with shadowgraph imaging is a valuable approach for dissolution process analysis.
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Modelling and shadowgraph imaging of cocrystal dissolution and assessment of in vitro antimicrobial activity for Sulfadimidine/4-aminosalicylic acid cocrystals
European Journal of Pharmaceutical Sciences, 2016Co-Authors: Dolores R. Serrano, Carolina Galiana, María Auxiliadora Dea-ayuela, Deirdre M. D’arcy, Tim Persoons, Anne Marie HealyAbstract:Abstract Purpose The aim of this work was to evaluate the influence of crystal habit on the dissolution and in vitro antibacterial and anitiprotozoal activity of Sulfadimidine:4-aminosalicylic acid cocrystals. Methods Cocrystals were produced via milling or solvent mediated processes. In vitro dissolution was carried out in the flow-through apparatus, with shadowgraph imaging and mechanistic mathematical models used to observe and simulate particle dissolution. In vitro activity was tested using agar diffusion assays. Results Cocrystallisation via milling produced small polyhedral crystals with antimicrobial activity significantly higher than Sulfadimidine alone, consistent with a fast dissolution rate which was matched only by cocrystals which were milled following solvent evaporation. Cocrystallisation by solvent evaporation (ethanol, acetone) or spray drying produced flattened, plate-like or quasi-spherical cocrystals, respectively, with more hydrophobic surfaces and greater tendency to form aggregates in aqueous media, limiting both the dissolution rate and in vitro activity. Deviation from predicted dissolution profiles was attributable to aggregation behaviour, supported by observations from shadowgraph imaging. Conclusions Aggregation behaviour during dissolution of cocrystals with different habits affected the dissolution rate, consistent with in vitro activity. Combining mechanistic models with shadowgraph imaging is a valuable approach for dissolution process analysis.
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a comparison of spray drying and milling in the production of amorphous dispersions of sulfathiazole polyvinylpyrrolidone and Sulfadimidine polyvinylpyrrolidone
Molecular Pharmaceutics, 2011Co-Authors: Vincent Caron, Lidia Tajber, Owen I Corrigan, Anne Marie HealyAbstract:Formulations containing amorphous active pharmaceutical ingredients (APIs) present great potential to overcome problems of limited bioavailability of poorly soluble APIs. In this paper, we directly compare for the first time spray drying and milling as methods to produce amorphous dispersions for two binary systems (poorly soluble API)/excipient: sulfathiazole (STZ)/polyvinylpyrrolidone (PVP) and Sulfadimidine (SDM)/PVP. The coprocessed mixtures were characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and intrinsic dissolution tests. PXRD and DSC confirmed that homogeneous glassy solutions (mixture with a single glass transition) of STZ/PVP were obtained for 0.05 ≤ XPVP (PVP weight fraction) < 1 by spray drying and for 0.6 ≤ XPVP < 1 by milling (at 400 rpm), and homogeneous glassy solutions of SDM/PVP were obtained for 0 < XPVP < 1 by spray drying and for 0.7 ≤ XPVP < 1 by milling. For these amorphous composites, the val...
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A comparison of spray drying and milling in the production of amorphous dispersions of sulfathiazole/polyvinylpyrrolidone and Sulfadimidine/polyvinylpyrrolidone.
Molecular Pharmaceutics, 2011Co-Authors: Vincent Caron, Lidia Tajber, Owen I Corrigan, Anne Marie HealyAbstract:Formulations containing amorphous active pharmaceutical ingredients (APIs) present great potential to overcome problems of limited bioavailability of poorly soluble APIs. In this paper, we directly compare for the first time spray drying and milling as methods to produce amorphous dispersions for two binary systems (poorly soluble API)/excipient: sulfathiazole (STZ)/polyvinylpyrrolidone (PVP) and Sulfadimidine (SDM)/PVP. The coprocessed mixtures were characterized by powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and intrinsic dissolution tests. PXRD and DSC confirmed that homogeneous glassy solutions (mixture with a single glass transition) of STZ/PVP were obtained for 0.05 ≤ XPVP (PVP weight fraction) < 1 by spray drying and for 0.6 ≤ XPVP < 1 by milling (at 400 rpm), and homogeneous glassy solutions of SDM/PVP were obtained for 0 < XPVP < 1 by spray drying and for 0.7 ≤ XPVP < 1 by milling. For these amorphous composites, the val...
Mino R. Caira - One of the best experts on this subject based on the ideXlab platform.
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effect of crystal packing on h bond parameters x ray structure of the Sulfadimidine p chlorobenzoic acid co crystal
Analytical Sciences: X-ray Structure Analysis Online, 2008Co-Authors: Roxana Lucaciu, Alexander F. Wildervanck, Corina Ionescu, Mino R. CairaAbstract:The X-ray structure of the 1:1 co-crystal (1) between the antibacterial drug Sulfadimidine (SD) and p-chlorobenzoic acid (PCL) is reported. Compound 1 crystallizes in the space group P21/c with a = 15.354(5)A, b = 14.433(4)A, c = 18.732(5)A, β = 94.540(5)°, and Z = 8. In the two independent co-crystal units, identical R22(8) hydrogen-bonded motifs occur, each involving the hydrogen bond SD(-SO2-N-H)…O=C(PCL) and the hydrogen bond PCL(O-H)…N(SD pyrimidinyl). A significant inequality of the two N…O distances in the chemically identical N-H…O=C hydrogen bonds indicates that such parameters can be strongly influenced by the crystal packing factors.
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Selective formation of hydrogen bonded cocrystals between a sulfonamide and aromatic carboxylic acids in the solid state
Journal of The Chemical Society-perkin Transactions 1, 1995Co-Authors: Mino R. Caira, Luigi R. Nassimbeni, Alexander F. WildervanckAbstract:Co-grinding Sulfadimidine [4-amino-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide] with several aromatic carboxylic acids in the solid state produces 1 : 1 hydrogen bonded cocrystals which are identical to those obtained from reaction between the components in solution. The kinetics of solid state formation of selected cocrystals have been measured using X-ray powder diffraction. Sulfadimidine selectively cocrystallizes with 2-aminobenzoic acid when the latter is present in binary mixtures of acids. Solid state reaction of the cocrystal Sulfadimidine·2-hydroxybenzoic acid with 2-aminobenzoic acid results in elimination of 2-hydroxybenzoic acid and formation of the cocrystal Sulfadimidine·2-aminobenzoic acid.
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Molecular complexes of sulfonamides. 2.1:1 complexes between drug molecules: Sulfadimidine-acetylsalicylic acid and Sulfadimidine-4-aminosalicylic acid
Journal of Crystallographic and Spectroscopic Research, 1992Co-Authors: Mino R. CairaAbstract:The preparation and crystal structures of the 1:1 complexes Sulfadimidine-acetylsalicylic acid ( I ) and Sulfadimidine-4-aminosalicylic acid ( II ) are described. Each complex unit is maintained by two intermolecular hydrogen bonds, namely N-H⋯O=C and N⋯H-O, involving the N atom of the sulfonamide group and one pyrimidine N atom of the sulfonamide and the carboxylic group of the acid. Molecular parameters for protonated complexed aspirin, as found in I, are reported for the first time and reveal a significantly different conformation from that of the uncomplexed aspirin molecule. The structure of the 4-aminosalicylic acid molecule does not change significantly on complexation with Sulfadimidine. Variation in the hydrogen bonded N⋯O distances in these complexes and their analogs is discussed.
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molecular complexes of sulfonamides part 1 1 1 complexes between Sulfadimidine 4 amino n 4 6 dimethyl 2 pyrimidinyl benzenesulfonamide and 2 and 4 aminobenzoic acids
Journal of Chemical Crystallography, 1991Co-Authors: Mino R. CairaAbstract:The crystal and molecular structures of the 1∶1 complexes Sulfadimidine·2-aminobenzoic acid (I) and Sulfadimidine·4-aminobenzoic acid (II) are described and compared with known structures containing Sulfadimidine. In each complex, molecular association is maintained by one N-H⋯O hydrogen bond, and one O-H⋯N hydrogen bond involving the imino N and one pyrimidinyl N atom of Sulfadimidine and the two carboxyl O atoms of the aromatic acid. The conformation of the Sulfadimidine molecule inII is unusual for anN1-substituted arylsulfonamide. Molecular dimensions for the complexed aminobenzoic acids are virtually the same as those reported for the free acids. Partial correlation between carboxylic acid strengths and the hydrogen bonded N⋯O distances is observed in Sulfadimidine complexes of this type.
Jianzhong Shen - One of the best experts on this subject based on the ideXlab platform.
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selection of anti Sulfadimidine specific scfvs from a hybridoma cell by eukaryotic ribosome display
PLOS ONE, 2009Co-Authors: Yonghua Qi, Shaochen Wang, Siyang Huang, Yongning Wu, Congming Wu, Suxia Zhang, Zhanhui Wang, Jianzhong ShenAbstract:BACKGROUND: Ribosome display technology has provided an alternative platform technology for the development of novel low-cost antibody based on evaluating antibiotics derived residues in food matrixes. METHODOLOGY/PRINCIPAL FINDINGS: In our current studies, the single chain variable fragments (scFvs) were selected from hybridoma cell lines against Sulfadimidine (SM(2)) by using a ribosome library technology. A DNA library of scFv antibody fragments was constructed for ribosome display, and then mRNA-ribosome-antibody (MRA) complexes were produced by a rabbit reticulocyte lysate system. The synthetic Sulfadimidine-ovalbumin (SM(2)-OVA) was used as an antigen to pan MRA complexes and putative scFv-encoding genes were recovered by RT-PCR in situ following each panning. After four rounds of ribosome display, the expression vector pCANTAB5E containing the selected specific scFv DNA was constructed and transformed into Escherichia coli HB2151. Three positive clones (SAS14, SAS68 and SAS71) were screened from 100 clones and had higher antibody activity and specificity to SM(2) by indirect ELISA. The three specific soluble scFvs were identified to be the same molecular weight (approximately 30 kDa) by Western-blotting analysis using anti-E tag antibodies, but they had different amino acids sequence by sequence analysis. CONCLUSIONS/SIGNIFICANCE: The selection of anti-SM(2) specific scFv by in vitro ribosome display technology will have an important significance for the development of novel immunodetection strategies for residual veterinary drugs.
Dolores R. Serrano - One of the best experts on this subject based on the ideXlab platform.
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modelling and shadowgraph imaging of cocrystal dissolution and assessment of in vitro antimicrobial activity for Sulfadimidine 4 aminosalicylic acid cocrystals
European Journal of Pharmaceutical Sciences, 2016Co-Authors: Dolores R. Serrano, Carolina Galiana, Tim Persoons, Deirdre M Darcy, Maria Auxiliadora Deaayuela, Anne Marie HealyAbstract:Abstract Purpose The aim of this work was to evaluate the influence of crystal habit on the dissolution and in vitro antibacterial and anitiprotozoal activity of Sulfadimidine:4-aminosalicylic acid cocrystals. Methods Cocrystals were produced via milling or solvent mediated processes. In vitro dissolution was carried out in the flow-through apparatus, with shadowgraph imaging and mechanistic mathematical models used to observe and simulate particle dissolution. In vitro activity was tested using agar diffusion assays. Results Cocrystallisation via milling produced small polyhedral crystals with antimicrobial activity significantly higher than Sulfadimidine alone, consistent with a fast dissolution rate which was matched only by cocrystals which were milled following solvent evaporation. Cocrystallisation by solvent evaporation (ethanol, acetone) or spray drying produced flattened, plate-like or quasi-spherical cocrystals, respectively, with more hydrophobic surfaces and greater tendency to form aggregates in aqueous media, limiting both the dissolution rate and in vitro activity. Deviation from predicted dissolution profiles was attributable to aggregation behaviour, supported by observations from shadowgraph imaging. Conclusions Aggregation behaviour during dissolution of cocrystals with different habits affected the dissolution rate, consistent with in vitro activity. Combining mechanistic models with shadowgraph imaging is a valuable approach for dissolution process analysis.
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Modelling and shadowgraph imaging of cocrystal dissolution and assessment of in vitro antimicrobial activity for Sulfadimidine/4-aminosalicylic acid cocrystals
European Journal of Pharmaceutical Sciences, 2016Co-Authors: Dolores R. Serrano, Carolina Galiana, María Auxiliadora Dea-ayuela, Deirdre M. D’arcy, Tim Persoons, Anne Marie HealyAbstract:Abstract Purpose The aim of this work was to evaluate the influence of crystal habit on the dissolution and in vitro antibacterial and anitiprotozoal activity of Sulfadimidine:4-aminosalicylic acid cocrystals. Methods Cocrystals were produced via milling or solvent mediated processes. In vitro dissolution was carried out in the flow-through apparatus, with shadowgraph imaging and mechanistic mathematical models used to observe and simulate particle dissolution. In vitro activity was tested using agar diffusion assays. Results Cocrystallisation via milling produced small polyhedral crystals with antimicrobial activity significantly higher than Sulfadimidine alone, consistent with a fast dissolution rate which was matched only by cocrystals which were milled following solvent evaporation. Cocrystallisation by solvent evaporation (ethanol, acetone) or spray drying produced flattened, plate-like or quasi-spherical cocrystals, respectively, with more hydrophobic surfaces and greater tendency to form aggregates in aqueous media, limiting both the dissolution rate and in vitro activity. Deviation from predicted dissolution profiles was attributable to aggregation behaviour, supported by observations from shadowgraph imaging. Conclusions Aggregation behaviour during dissolution of cocrystals with different habits affected the dissolution rate, consistent with in vitro activity. Combining mechanistic models with shadowgraph imaging is a valuable approach for dissolution process analysis.
N Sardone - One of the best experts on this subject based on the ideXlab platform.
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trimethoprim Sulfadimidine 1 2 molecular complex monohydrate
Acta Crystallographica Section C-crystal Structure Communications, 1997Co-Authors: N Sardone, Giampiero Bettinetti, Milena Lillina SorrentiAbstract:In the title compound, C14H18N4O3.2C12H14N4O2S.H2O, trimethoprim [5-(3,4,5-trimethoxybenzyl)pyrimidine-2,4diamine, TMP] interacts with one Sulfadimidine [4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide, SDMD] molecule through two N-H⋯N hydrogen bonds forming an eight-membered ring, as in the 1:1 methanolate complex, with no proton transfer from the imino sulfonamide N atom to the pyrimidine N atom of the partner. Association with the second Sulfadimidine molecule (SDMD') occurs through an N-H⋯N interaction involving the same pyrimidine N atom of TMP (which therefore acts as a double acceptor) and the NH imino group of the sulfonamide. The water molecule bridges the sulfonamido O atom and the p-aminophenyl group of SDMD' of two molecular complex units.
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Trimethoprim–Sulfadimidine 1:2 Molecular Complex Monohydrate
Acta Crystallographica Section C-crystal Structure Communications, 1997Co-Authors: N Sardone, Giampiero Bettinetti, Milena Lillina SorrentiAbstract:In the title compound, C14H18N4O3.2C12H14N4O2S.H2O, trimethoprim [5-(3,4,5-trimethoxybenzyl)pyrimidine-2,4diamine, TMP] interacts with one Sulfadimidine [4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide, SDMD] molecule through two N-H⋯N hydrogen bonds forming an eight-membered ring, as in the 1:1 methanolate complex, with no proton transfer from the imino sulfonamide N atom to the pyrimidine N atom of the partner. Association with the second Sulfadimidine molecule (SDMD') occurs through an N-H⋯N interaction involving the same pyrimidine N atom of TMP (which therefore acts as a double acceptor) and the NH imino group of the sulfonamide. The water molecule bridges the sulfonamido O atom and the p-aminophenyl group of SDMD' of two molecular complex units.
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methanol solvate of the 1 1 molecular complex of trimethoprim and Sulfadimidine
Acta Crystallographica Section C-crystal Structure Communications, 1997Co-Authors: Giampiero Bettinetti, N SardoneAbstract:In the title complex, C 14 H 18 N 4 O 3 .Cl 2 H 14 N 4 O 2 S.CH 4 O, the molecular association between trimethoprim { 5-[(3,4,5-trimethoxyphenyl)methyl]pyrimidine-2,4-diamine; TMP} and Sulfadimidine [4-amino-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulfonamide; SDMD] is maintained by two N-H...N hydrogen bonds with no proton transfer from the sulfonamide imino N atom to the pyrimidine N atom of TMP. The methanol solvate molecule is linked to an O atom of the sulfonamido group through a strong O-H...O interaction and does not seem to play an important role in the crystal-packing stabilization.
