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AAPS PharmSciTech. 2006 March; 7(1): E199–E205.
Published online 2006 March 24. doi:  10.1208/pt070128
PMCID: PMC2750735

Porous polystyrene beads as carriers for self-emulsifying system containing loratadine


The aim of this study was to formulate a self-emulsifying system (SES) containing a lipophilic drug, loratadine, and to explore the potential of preformed porous polystyrene beads (PPB) to act as carriers for such SES. Isotropic SES was formulated, which comprised Captex 200 (63% wt/wt), Cremophore EL (16% wt/wt), Capmul MCM (16% wt/wt), and loratadine (5% wt/wt). SES was evaluated for droplet size, drug content, and in vitro drug release. SES was loaded into preformed and characterized PPB using solvent evaporation method. SES-loaded PPB were evaluated using scanning electron microscopy (SEM) for density, specific surface area (SBET), loading efficiency, drug content, and in vitro drug release. After SES loading, specific surface area reduced drastically, indicating filling of PPB micropores with SES. Loading efficiency was least for small size (SS) and comparable for medium size (MS) and large size (LS) PPB fractions. In vitro drug release was rapid in case of SS beads due to the presence of SES near to surface. LS fraction showed inadequate drug release owing to presence of deeper micropores that resisted outward diffusion of entrapped SES. Leaching of SES from micropores was the rate-limiting step for drug release. Geometrical features such as bead size and pore architecture of PPB were found to govern the loading efficiency and in vitro drug release from SES-loaded PPB.

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Selected References

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1. Gursoy RN, Benita S. Self-emulsifying drug delivery systems for improved oral delivery of lipophilic drugs. Biomed Pharmacother. 2004;58:173–182. doi: 10.1016/j.biopha.2004.02.001. [PubMed] [Cross Ref]
2. Pouton CW. SEDDS: assessment of the efficiency of emulsification. Int J Pharm. 1985;27:335–348. doi: 10.1016/0378-5173(85)90081-X. [Cross Ref]
3. Charman SA, Charman WN, Rogge MC, Wilson TD, Pouton CW. Self-emulsifying drug delivery systems: formulation and biopharmaceutical evaluation of an investigational lipophilic compound. Pharm Res. 1992;9:87–93. doi: 10.1023/A:1018987928936. [PubMed] [Cross Ref]
4. Shah NH, Carvajal MT, Patel CI, Infeld NH, Malick AW. Self-emulsifying drug delivery systems (SEDDS) with polyglycolyzed glycerides for improving in vitro dissolution and oral absorption of lipophilic drugs. Int J Pharm. 1994;106:15–23. doi: 10.1016/0378-5173(94)90271-2. [Cross Ref]
5. Yang KY, Glemza R, Jarowski CI. Effect of amorphous silicon dioxide on drug dissolution. J Pharm Sci. 1979;68:560–565. doi: 10.1002/jps.2600680511. [PubMed] [Cross Ref]
6. Liao C, Jarowski CI. Dissolution rates of corticoid solutions dispersed on silicas. J Pharm Sci. 1984;73:401–403. doi: 10.1002/jps.2600730330. [PubMed] [Cross Ref]
7. Spireas SS, Jarowski CI, Rohera BD. Powdered solution technology: principles and mechanism. Pharm Res. 1992;9:1351–1358. doi: 10.1023/A:1015877905988. [PubMed] [Cross Ref]
8. Spireas S, Sadu S, Grover R. In vitro release evaluation of hydrocortisone liquisolid tablets. J Pharm Sci. 1998;87:867–872. doi: 10.1021/js970346g. [PubMed] [Cross Ref]
9. Nazzal S, Nutan M, Palamakula A, Shah R, Zaghloul AA, Khan MA. Optimization of self-nanoemulsified tablet dosage from of ubiquinone using response surface methodology: effect of formulation ingredients. Int J Pharm. 2002;240:103–114. doi: 10.1016/S0378-5173(02)00130-8. [PubMed] [Cross Ref]
10. Attama AA, Nzekwe IT, Nnamani PO, Adikwu MU, Onugu CO. The use of solid self-emulsifying systems in the delivery of diclofenac. Int J Pharm. 2003;262:23–28. doi: 10.1016/S0378-5173(03)00315-6. [PubMed] [Cross Ref]
11. Booth SW, Clarke A, Newton JM, inventors. Spheronized self-emulsifying system for hydrophobic and water sensitive agents. US patent 6 630 150. October 7, 2003.
12. Schwarz J, inventor. Solid self-emulsifying dosage form for improved delivery of poorly soluble hydrophobic compounds and the process of preparation thereof. US patent application 20030072798. April 17, 2003.
13. Patil P, Joshi P, Paradkar A. Effect of formulation variables on preparation and evaluation of gelled self-emulsifying drug delivery system (SEDDS) of ketoprofen. AAPS PharmSciTech. 2004;5:E42–E42. doi: 10.1208/pt050342. [PMC free article] [PubMed] [Cross Ref]
14. Øye G, Roucoules V, Cameron AM, et al. Plasmachemical amine functionalization of porous polystyrene beads: the importance of pore architecture. Langmur. 2002;18:8996–8999. doi: 10.1021/la0202935. [Cross Ref]
15. Rigby SP, Fletcher RS, Riley SN. Characterization of porous solids using integrated nitrogen sorption and mercury porosimetry. Chem Eng Sci. 2004;59:41–51. doi: 10.1016/j.ces.2003.09.017. [Cross Ref]
16. Won R, inventor. Method for delivering an active ingredient by controlled time release utilizing a novel delivery vehicle which can be prepared by a process utilizing an active ingredient as a porogen. US patent 4 690 825. September 1, 1987.
17. Barby D, Haq Z, inventors. Low density porous cross-linked materials and their preparation and use as carriers for included liquids. US patent 4 522 953. June 11, 1985.
18. Landgraf W, Li NH, Benson JR. Polymer microcarrier exhibiting zero order release. Drug Deliv Technol. 2003;3:56–63.
19. Iconomopoulou SM, Andreopoulou AK, Soto A, Kallitsis JK, Voyiatzis GA. Incorporation of low molecular weight biocodes into polystyrene-divinyl benzene beads with controlled release characteristics. J Control Release. 2005;102:223–233. doi: 10.1016/j.jconrel.2004.10.006. [PubMed] [Cross Ref]
20. Khan MZI, Rasul D, Zanoski R, et al. Classification of loratadine based on the biopharmaceutics drug classification concept and possible in vitro-in vivo correlation. Biol Pharm Bull. 2004;27:1630–1635. doi: 10.1248/bpb.27.1630. [PubMed] [Cross Ref]
21. Salis A, Sanjust E, Solinas V, Monduzzi M. Characterization of Accurel MP1004 polypropylene powder and its use as a support for lipase immobilization. J Mol Catal, B Enzym. 2003;24–25:75–82. doi: 10.1016/S1381-1177(03)00112-7. [Cross Ref]
22. Peck GE, editor. Separation. 20th ed. Philadelphia, PA: Lippincott Williams and Wilkins; 2000. pp. 669–680.
23. Li ZZ, Wen LX, Shao L, Chen JF. Fabrication of porous hollow silica nanoparticles and their applications in drug release control. J Control Release. 2004;98:245–254. doi: 10.1016/j.jconrel.2004.04.019. [PubMed] [Cross Ref]

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