Thermochimica Acta, Vol.340-341, 147-164, 1999
Investigation of the applicability of a titration method to determine parameters related to porosity in pharmaceutical suspension dosage forms
The purpose of this study was to find a more efficient method for determining the porosity, or voids, using an insoluble powder in a pharmaceutical suspension. In a random arrangement of uniform spheres the only concern is with the limits of porosity existing within that collection. Theoretically, no equation can completely describe the physical properties of a sediment in a liquid medium without considering its particle size, size distribution, shape features, surface characteristics, etc. For the ideal case dealing with uniform spherical particles, it is expected that the plot of the weight of solid versus the volume of liquid used to fill the voids should be a straight line with zero intercept. A new titration method has been proposed to directly measure the immediate pore volume between particles in the suspension. Further investigation is required to determine its sensitivity such that it may provide a means of differentiating the nature of the particle-particle and particle-liquid attractive forces within a given pharmaceutical suspension system.