Effects of moisture content, shape and particle size of composite particles of rice starch and microcrystalline cellulose on tabletting

Abstract

To investigate the effects of moisture content, shape and particle size of composite particles between rice starch (RS) and microcrystalline cellulose (MCC) on tabletting properties. The composite particles (RS:MCC) which composed of RS and MCC in the ratio of 7:3 were prepared by spray drying technique. MCC from two sources were used, CEOLUS® PH 101 and COMPRECEL®. Two groups of MCC were used, that passing through a sieve number 45 having an opening aperture of 355 µm (CS) and that its size was reduced by jet mill (CJM). It was found that using CS produced composite particles in “rugby ball” shape while using CJM gave composite particles of spherical shape. Powder characterizations of RS:MCC prepared by using MCC from two sources gave similar flowability index. However, the hardness of the 500 mg and 350 mg RS:MCC tablets composed of CEOLUS® PH 101 was higher than composite particles using COMPRECEL®. The composite particles using CEOLUS® PH 101 which having 7.01, 10.79 and 15.73 percent moisture content exhibited different tabletting properties in particular the hardness of tablet. Capping of tablet was found at 15.73 percent of moisture content level. Moreover, comparing with commercial spray dried rice starch without MCC (Eratab®), the Eratab® tablets were likely to be friable than RS:MCC tablets at the moisture content of approximately 10.79%. The relationship of particle sizes of RS:MCC composite particles with their tabletting properties was unclear. Perhaps, the particle size range of RS:MCC composite particles chosen for the study was inappropriate. Particle shape of RS:MCC composite particles especially affected on the hardness of 350 mg tablet when compressed with lower force as 1 and 1.5 metric tons. Tablets made from spherical shape RS:MCC (using CJM as starting materials) was harder than those of made from “rugby ball” shape RS:MCC (using CS as starting materials).