Abstract

DRY POWDER INHALATION FORMULATION CONTAINING SPRAY DRIED ESSENTIAL OIL FOR PULMONARY DELIVERY

Aishwarya A. Mane* and Dr. Amrita Bajaj

ABSTRACT

The study embroils development of pulmonary drug delivery system based on dry powder inhalers containing microencapsulated essential oil and characterization of the developed formulation. Microparticles of eucalyptus oil to be incorporated for pulmonary delivery was formulated using technique of microencapsulation of inclusion complex by spray drying. Encapsulating and complexing materials used were Gum acacia, maltodextrin & betacyclodextrin. This dry powder was then blended with Respitose ML006 & transfer inti Aphaler DPI device. To determine the eucalyptol content, a gas chromatography method was developed using the solvent ethanol, nitrogen as the carrier gas and 15% OV17 column; and validated for various parameters like linearity (R2of 0.9998). The encapsulation efficiency of the formulation procedure determined by GC analytical method was 93.95 % w/w. Formulated powder of eucalyptus oil exhibited excellent flow properties. The SEM studies confirmed the encapsulation of essential oil. In vitro pulmonary deposition studies were carried out using twin stage impinger apparatus & it showed high respirable fraction up to 38 %. Formulated powder of eucalyptus oil was found to be stable over a period of 2 months. From the current study it could be concluded that the technique of microencapsulation of inclusion complex by spray drying enhanced the availability and stability of eucalyptus oil. The developed DPI formulations containing natural oil hold promising future due to reduction in problems associated with inhalation of eucalyptus oil and have potential for improving patient compliance & showed high potential for successful pulmonary delivery.

Keywords: Dry powder inhalers, Eucalyptus oil, Microencapsulation, Spray drying, Gas chromatography, Twin stage impinger.