Spray-dried carbamazepine-loaded chitosan and HPMC microspheres: preparation and characterisation

Abstract

In this study, the potential of the spray-drying technique for preparing microspheres able to modify the release profile of carbamazepine was investigated. Low-, medium- and high-molecular-weight chitosan and hydroxypropyl methylcellulose (HPMC) in different drug-polymer ratios were used for the preparation of microspheres. The microspheres, characterized by X-ray powder diffractometry (XRD) and differential scanning calorimetry (DSC), were also studied with respect to particle size distribution, drug content and drug release. The results indicated that the entrapment efficiency (EE), as well as carbamazepine release profile, depended on polymeric composition and drug-polymer ratios of the microspheres prepared. The best entrapment efficiencies were obtained when chitosan of low-molecular-weight (CL) or HPMC were used for the microencapsulation. For all types of polymer used, the microspheres with low carbamazepine loading (6.3% w/w) showed better control of drug release than the microspheres with higher drug loadings. The HPMC microspheres showed the slowest carbamazepine release profile with no initial burst effect. Carbamazepine release profiles from ternary systems, carbamazepine-CL-HPMC microspheres, depended mostly on HPMC content and showed similar carbamazepine release profile as CL microspheres when HPMC content was low (9:1 CL-HPMC ratio, w/w). Otherwise, the carbamazepine release from CL-HPMC microspheres was remarkably faster than from either chitosan or HPMC microspheres. The release profile of carbamazepine from the microspheres was highly correlated with the crystalline changes occurring in the matrix.

Improvement of Albendazole Dissolution by Preparing Microparticles Using Spray-Drying Technique

“…Examples of successfully tested-drugs which improved their dissolution by spray drying technique are indomethacin [17], tolbutamide [18], carbamazepine [19], and ketoprofen [20].…”

Two-stage optimization process for formulation of chitosan microspheres

“…1,2 Chitosan microspheres have been prepared by chemical denaturation, 3,4 ion-induced coagulation, 2,5 and spray-drying methods. 6,7 Of these methods, the most common method used to prepare chitosan microspheres is the chemical denaturation method. Chemical denaturation involves denaturation of chitosan present in the inner phase of water/oil (w/o) emulsion.…”

Optimization of prednisolone acetate-loaded chitosan microspheres using a 23factorial design for preventing restenosis

“…The total amount of PA was calculated from the aliquots of each extract. The encapsulation efficiency was calculated (Filipovic-Grcic et al, 2003). All analyses were carried out in triplicate.…”