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Agglomeration effects on the drying and dehydration stability of pharmaceutical acicular hydrate / Ji Yi Khoo in Industrial & engineering chemistry research, Vol. 49 N° 1 (Janvier 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 1 (Janvier 2010) . - pp. 422–427 Titre : Agglomeration effects on the drying and dehydration stability of pharmaceutical acicular hydrate : carbamazepine dihydrate Type de document : texte imprimé Auteurs : Ji Yi Khoo, Auteur ; Jerry Y. Y. Heng, Auteur ; Daryl R. Williams, Auteur Année de publication : 2010 Article en page(s) : pp. 422–427 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Agglomeration--Effects--Drying--Dehydration--Stability--Pharmaceutical--Acicular--Hydrate--Carbamazepine--Dihydrate Résumé : The effects of agglomeration on the dehydration kinetics and stability of carbamazepine dihydrate were investigated and are reported here. The prepared dihydrate agglomerates were sieved into six particle size distributions, ranging from 75 to ∼1800 μm, prior to gravimetric dehydration studies. It was concluded that when these agglomerates exceed a critical agglomerates size, they then retain an excess amount of physically adsorbed (unbound) water relative to the smaller agglomerate sizes. Specifically, agglomerates with particle diameter >1400 μm held up to 57.2 wt % of unbound water, residing within the funicular regime of moisture saturation. These larger agglomerates exhibit a distinct and densely packed particle structure, leading to a relatively more stable dihydrate, having a lower critical humidity of 20% RH (0.0039 kgwater/kgair) at 25 °C, than those agglomerates without inclusion of unbound water. This work demonstrates that the moisture stability performance of agglomerated solids is dependent both on the intrinsic water sorption properties of the component materials as well as the local microstructure that evolves within the agglomerated solids. Furthermore, this work also demonstrates that the moisture stability of a solid state form can be strongly influenced by local particle microstructure, which thus provides another strategy for improving moisture stability of formulated products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011968 [article] Agglomeration effects on the drying and dehydration stability of pharmaceutical acicular hydrate : carbamazepine dihydrate [texte imprimé] / Ji Yi Khoo, Auteur ; Jerry Y. Y. Heng, Auteur ; Daryl R. Williams, Auteur . - 2010 . - pp. 422–427. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 1 (Janvier 2010) . - pp. 422–427 Mots-clés : Agglomeration--Effects--Drying--Dehydration--Stability--Pharmaceutical--Acicular--Hydrate--Carbamazepine--Dihydrate Résumé : The effects of agglomeration on the dehydration kinetics and stability of carbamazepine dihydrate were investigated and are reported here. The prepared dihydrate agglomerates were sieved into six particle size distributions, ranging from 75 to ∼1800 μm, prior to gravimetric dehydration studies. It was concluded that when these agglomerates exceed a critical agglomerates size, they then retain an excess amount of physically adsorbed (unbound) water relative to the smaller agglomerate sizes. Specifically, agglomerates with particle diameter >1400 μm held up to 57.2 wt % of unbound water, residing within the funicular regime of moisture saturation. These larger agglomerates exhibit a distinct and densely packed particle structure, leading to a relatively more stable dihydrate, having a lower critical humidity of 20% RH (0.0039 kgwater/kgair) at 25 °C, than those agglomerates without inclusion of unbound water. This work demonstrates that the moisture stability performance of agglomerated solids is dependent both on the intrinsic water sorption properties of the component materials as well as the local microstructure that evolves within the agglomerated solids. Furthermore, this work also demonstrates that the moisture stability of a solid state form can be strongly influenced by local particle microstructure, which thus provides another strategy for improving moisture stability of formulated products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011968

Role of surface chemistry and energetics in high shear wet granulation / Raimundo Ho in Industrial & engineering chemistry research, Vol. 50 N° 16 (Août 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 16 (Août 2011) . - pp. 9642–9649 Titre : Role of surface chemistry and energetics in high shear wet granulation Type de document : texte imprimé Auteurs : Raimundo Ho, Auteur ; Sarah E. Dilworth, Auteur ; Daryl R. Williams, Auteur Année de publication : 2011 Article en page(s) : pp. 9642–9649 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Surface  chemistry  Energetics Résumé : This article presents a detailed study of the role of solid state surface chemistry on the high shear granulation performance of organic pharmaceutical solids. The sole effect of powder surface chemistry on granulation performance was investigated by coagglomerating untreated and silanized d-mannitol powder from a narrow sieve fraction in a high shear process. The wetting performance by polyvinylpyrrolidone (PVP) binder solutions was quantified using experimentally determined thermodynamic spreading coefficients, calculated from surface energy heterogeneity distributions obtained via inverse gas chromatography (IGC) measurements. Increases in binder wettability of the formulations correlated with increases in both granule size and compressive elastic moduli, which are attributed to an increase in interparticle contacts. In conclusion, starting materials surface chemistry plays a crucial role in final granule properties, even in highly agitated processes such as high shear granulation. The comprehensive characterization of powder surface properties is necessary to facilitate the manufacture of granules with controllable critical attributes. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009263 [article] Role of surface chemistry and energetics in high shear wet granulation [texte imprimé] / Raimundo Ho, Auteur ; Sarah E. Dilworth, Auteur ; Daryl R. Williams, Auteur . - 2011 . - pp. 9642–9649. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 16 (Août 2011) . - pp. 9642–9649 Mots-clés : Surface  chemistry  Energetics Résumé : This article presents a detailed study of the role of solid state surface chemistry on the high shear granulation performance of organic pharmaceutical solids. The sole effect of powder surface chemistry on granulation performance was investigated by coagglomerating untreated and silanized d-mannitol powder from a narrow sieve fraction in a high shear process. The wetting performance by polyvinylpyrrolidone (PVP) binder solutions was quantified using experimentally determined thermodynamic spreading coefficients, calculated from surface energy heterogeneity distributions obtained via inverse gas chromatography (IGC) measurements. Increases in binder wettability of the formulations correlated with increases in both granule size and compressive elastic moduli, which are attributed to an increase in interparticle contacts. In conclusion, starting materials surface chemistry plays a crucial role in final granule properties, even in highly agitated processes such as high shear granulation. The comprehensive characterization of powder surface properties is necessary to facilitate the manufacture of granules with controllable critical attributes. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009263