@prefix prodottidellaricerca: . @prefix istituto: . @prefix prodotto: . istituto:CDS063 prodottidellaricerca:prodotto prodotto:ID39996 . @prefix pubblicazioni: . @prefix unitaDiPersonaleInterno: . unitaDiPersonaleInterno:MATRICOLA20474 pubblicazioni:autoreCNRDi prodotto:ID39996 . unitaDiPersonaleInterno:MATRICOLA9511 pubblicazioni:autoreCNRDi prodotto:ID39996 . @prefix modulo: . modulo:ID2682 prodottidellaricerca:prodotto prodotto:ID39996 . @prefix rdf: . @prefix retescientifica: . prodotto:ID39996 rdf:type retescientifica:ProdottoDellaRicerca , prodotto:TIPO1101 . @prefix rdfs: . prodotto:ID39996 rdfs:label "Calorimetric relaxation in pharmaceutical molecular glasses and its utility in understanding their stability against crystallization (Articolo in rivista)"@en . @prefix xsd: . prodotto:ID39996 pubblicazioni:anno "2008-01-01T00:00:00+01:00"^^xsd:gYear ; pubblicazioni:doi "10.1021/jp801794a"^^xsd:string . @prefix skos: . prodotto:ID39996 skos:altLabel "
Tombari E.; Ferrari C.; Johari G.P.; Shanker R.M. (2008)
Calorimetric relaxation in pharmaceutical molecular glasses and its utility in understanding their stability against crystallization
in The journal of physical chemistry. B
"^^rdf:HTML ; pubblicazioni:autori "Tombari E.; Ferrari C.; Johari G.P.; Shanker R.M."^^xsd:string ; pubblicazioni:paginaInizio "10806"^^xsd:string ; pubblicazioni:paginaFine "10814"^^xsd:string ; pubblicazioni:numeroVolume "112"^^xsd:string . @prefix ns11: . prodotto:ID39996 pubblicazioni:rivista ns11:ID195845 ; skos:note "ISI Web of Science (WOS)"^^xsd:string ; pubblicazioni:affiliazioni "Istituto per i Processi Chimico-Fisici del CNR, Via G. Moruzzi 1, 56124 Pisa, Italy\nDepartment of Materials Science and Engineering, McMaster UniVersity, Hamilton, Ontario L8S 4L7, Canada\nGroton Laboratories, Pfizer Inc., Groton, Connecticut 06340"^^xsd:string ; pubblicazioni:titolo "Calorimetric relaxation in pharmaceutical molecular glasses and its utility in understanding their stability against crystallization"^^xsd:string ; prodottidellaricerca:abstract "Glassy states of three pharmaceuticals, acetaminophen, griseofulvin. and nifedipine, and an acetaminophen-aspirin (1:1 mol) alloy were made by slow cooling of the melt and Studied by calorimetry. Measurements were performed by cooling and heating at significantly slow rates of 20 K/h, which were comparable to the rate used in adiabatic calorimetry. The results were modeled in terms of a nonexponential, nonlinear structural relaxation. The calorimetric relaxation of all four pharmaceutical samples were less nonexponential than those of polymeric or inorganic glasses, and this finding was attributed to additional contributions to energy change that Would arise from temperature and time dependent variation in the hydrogen bond population, the extent of isomerization, and/or the ionic equilibria that exist in these materials. Four calculated and relevant parameters for the pharmaceutical samples were, ln A = -1837 beta = 0.75, x = 0.4, and Delta h* = 457 kJ/mol for acetaminoplien, ln A = -170, beta = 0.75, x = 0.45, and Delta h* = 516 kJ/mol for griseofulvin, ln A = -189, beta = 0.69, x = 0.39, and Delta h* = 503 kJ/mnol for nifedipine, and ln A = -160, beta = 0.70, x 0.50, and Delta h* = 363 kJ/mol for the acetaminophen-aspirin alloy. The significance of these parameters and, in particular, their values are discussed in the context of the stability of the pharmaceuticals against crystallization and compared against the significance of the localized motions of the JG relaxation in the same context. Acetaminophen was found to be significantly more prone to crystallization on heating than the other two pharmaceuticals as well as the acetaminophen-aspirin alloy."@en ; prodottidellaricerca:prodottoDi modulo:ID2682 , istituto:CDS063 ; pubblicazioni:autoreCNR unitaDiPersonaleInterno:MATRICOLA9511 , unitaDiPersonaleInterno:MATRICOLA20474 . @prefix parolechiave: . prodotto:ID39996 parolechiave:insiemeDiParoleChiave . ns11:ID195845 pubblicazioni:rivistaDi prodotto:ID39996 . parolechiave:insiemeDiParoleChiaveDi prodotto:ID39996 .