Čes. slov. farm. 2013, 62(1):28-34

Diclofenac sodium entrapment and release from halloysite nanotubules

Kateřina Krejčová¹, Patrick B. Deasy¹, Miloslava Rabišková^2,*

¹ School of Pharmacy, Trinity College Dublin, Dublin, Ireland

² Department of Pharmaceutical Technology, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic

Halloysite was found to have interesting nanotubular geometry viable for the entrapment of various active agents. In this experiment, the ability of hollow halloysite cylinders to entrap the anionic model drug diclofenac sodium and to retard drug dissolution rate was investigated. Drugs could be incorporated into layered tubules via three different mechanisms: adsorption, intercalation and tubular entrapment. Based on the adsorption studies, some diclofenac sodium was shown to be adsorbed to the polyionic mineral surface despite its permanent negative charge. The X-ray powder diffraction analysis (XRPD) results did not prove any intercalation reaction to occur. The most important drug-loading mechanism involved the tubular entrapment with encapsulation efficiency 48.1%. The drug release from halloysite was prolonged in comparison with the dissolution of pure drug. Halloysite itself as well as halloysite loaded with the drug proved to be appropriate material to form pellets by extrusion /spheronization method.

Keywords: halloysite; diclofenac sodium; drug entrapment; pellets; prolonged drug release

Received: December 12, 2012; Accepted: January 16, 2013; Published: January 1, 2013  Show citation