Evaluation of Ludipress as a “Multipurpose Excipeent” for Direct Compression: Part I: Powder Characteristics and Tableting Properties

Abstract
The powder characteristics and tableting properties of Ludipress, a lactose-based, free flowing granule containing povidone and crospovidone have been evaluated and compared to the physical blend of the base materials in Ludipress and to other filler/binders including Cellactose and Avicel PH 200. The data were determined in order to evaluate flowability, bulk density, tapped density, Hausner ratio, angle of repose and particle size distribution. The particle morphology and constitution were examined using scanning electron microscopy (SEM). Differential scanning calorimetry (DSC) was used to detect differences between lactose based products. Several Ludipress samples exhibited a good batch-to-batch uniformity and flow characteristics compared to the physical blend and other excipients investigated. The tableting parameters tested were crushing strength, friability and disintegration time. The ability to form coherent compacts was similar for Ludipress, Cellactose and Avicel PH 200, whereas tablets made from the physical blend resulted significantly softer. Determination of tablet disintegration time revealed a disintegration time minimum at about 100 MPa for Ludipress compacts. By augmenting compaction load from 100 to 185 MPa Cellactose showed an increase in disintegration time to more than 20 minutes. The disintegration times of Avicel PH 200 compacts were nearly constant and were also the shortest in the compaction load range examined.