Accelerated ketoprofen release from polymeric matrices: importance of the homogeneity/heterogeneity of excipient distribution.
Polymeric matrices loaded with 10-50% ketoprofen were prepared by hot-melt extrusion or spray-drying. Eudragit E, PVP, PVPVA and HPMC were studied as matrix formers. Binary "drug-Eudragit E" as well as ternary "drug-Eudragit E-PVP", "drug-Eudragit E-PVPVA" and "drug-Eudragit E-HPMC" combinations were investigated and characterized by optical macro/microscopy, SEM, particle size measurements, mDSC, X-ray diffraction and in vitro drug release studies in 0.1 M HCl. In all cases ketoprofen release was much faster compared to a commercially available product and the dissolution of the drug powder (as received). Super-saturated solutions were obtained, which were stable during at least 2 h. Importantly, not only the composition of the systems, but also their inner structure potentially significantly affected the resulting ketoprofen release kinetics: For instance, spray-drying ternary ketoprofen:Eudragit E:HPMC combinations led to a more homogenous HPMC distribution within the systems than hot-melt extrusion, as revealed by mDSC and X-ray diffraction. This more homogenous HPMC distribution resulted in more pronounced hindrance for water and drug diffusion and, thus, slower drug release from spray-dried powder compared to hot-melt extrudates of identical composition. This "homogeneity/heterogeneity effect" even overcompensated the "system size effect": the surface exposed to the release medium was much larger in the case of the spray-dried powder. All formulations were stable during storage at ambient conditions in open vials.
Université de Lille 2, College of Pharmacy, 3 Rue du Prof. Laguesse, 59006 Lille, France; INSERM U 1008, Controlled Drug Delivery Systems and Biomaterials, 3 Rue du Prof. Laguesse, 59006 Lille, France.
E
E
Gue
J F
JF
Willart
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S
Muschert
F
F
Danede
E
E
Delcourt
M
M
Descamps
J
J
Siepmann
D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D004339:Drug Compounding; D005079:Excipients / Q000737:chemistry*; D007660:Ketoprofen / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012995:Solubility
D000894:Anti-Inflammatory Agents, Non-Steroidal; D005079:Excipients; D011108:Polymers; D007660:Ketoprofen
Hot-melt extrusion; Ketoprofen, Eudragit(®) E; Poorly soluble drugs; Spray-drying