Application of a novel 3-fluid nozzle spray drying process for the microencapsulation of therapeutic agents using incompatible drug-polymer solutions
The aim of this study was to evaluate a novel 3-fluid concentric nozzle (3-N) spray drying process for the microencapsulation of omeprazole sodium (OME) using Eudragit L100 (EL100). Feed solutions containing OME and/or EL100 in ethanol were assessed visually for OME stability. Addition of OME solution to EL100 solution resulted in precipitation of OME followed by degradation of OME reflected by a colour change from colourless to purple and brown. This was related to the low pH of 2.8 of the EL100 solution at which OME is unstable. Precipitation and progressive discoloration of the 2-fluid nozzle (2-N) feed solution was observed over the spray drying time course. In contrast, 3-N solutions of EL100 or OME in ethanol were stable over the spray drying period. Microparticles prepared using either nozzle showed similar characteristics and outer morphology however the internal morphology was different. DSC showed a homogenous matrix of drug and polymer for 2-N microparticles while 3-N microparticles had defined drug and polymer regions distributed as core and coat. The results of this study demonstrate that the novel 3-N spray drying process can allow the microencapsulation of a drug using an incompatible polymer and maintain the drug and polymer in separate regions of the microparticles.
KeywordsSpray drying Three-fluid nozzle Two-fluid nozzle Microencapsulation Incompatible OME sodium Eudragit L100
- Figueiras, A., R.A. Carvalho, L. Ribeiro, J.J. Torres-Labandeira, and F.J. Veiga. 2007. Solid-state characterization and dissolution profiles of the inclusion complexes of omeprazole with native and chemically modified beta-cyclodextrin. European Journal of Pharmaceutics and Biopharmaceutics 67: 531–539.CrossRefPubMedGoogle Scholar
- Garg, S., D. Svirskis, M. Al-Kabban, S. Farhan, M. Komeshi, J. Lee, Q. Liu, S. Naidoo, and T. Kairuz. 2009. Chemical stability of extemporaneously compounded omeprazole formulations: A comparison of two methods of compounding. International Journal of Pharmaceutical Compounding 13: 250–253.Google Scholar
- Harsha, S., Al-Khars, M., Al-Hassan, M., Kumar, N. P., Nair, A.B., Attimarad, M., and B.E. Al-Dhubiab. 2013. Pharmacokinetics and tissue distribution of spray-dried carboplatin microspheres: Lung targeting via intravenous route. Archives of Pharmacal Research 1–9.Google Scholar
- Ramtoola, Z. 2008. Method of producing microcapsules. WO Patent 2,008,056,344.Google Scholar
- Swarbrick, J., and J.C. Boylan. 1996. Encyclopedia of pharmaceutical technology. New York: Marcel Dekker.Google Scholar