Effect of Maize Starch Excipient Properties on Drug Release Rate

Multivariate feed forward process control and optimization of an industrial, granulation based tablet manufacturing line using historical data

The purpose of this work was to understand the variability in disintegration time and tableting yield of high drug load (>60%) tablets prepared by batch-wise high shear wet granulation. The novelty of the study is the use of multivariate methods (Batch Evolution Models - BEMs and Batch Level Models - BLMs) to enhance process control, with a feed forward component, using prediction models built from a historical dataset acquired for 95 industrial scale batches. Time dependent process variables and significant influences on investigated parameters were identified. Prediction of output from input was tested with Partial Least Squares (PLS) and Artificial Neural Network (ANN) modeling. A reliable prediction ability was achieved for granulation water amount (±2 kg in a 16-31 kg range), tableting speed (±5000 tablets/h in a 23,000-72,500 tabl./h range) and disintegration time of cores (±100 s; in a 250-900 s range). Offsets from the optimal process evolution and certain raw material properties were correlated with differences observed in the output variables. Improvement options were identified for 80% of the batches with high disintegration time. Hence, the trained models can be applied for systematic process improvement, enabling feed forward control.

Investigation of Dissolution Mechanism and Release Kinetics of Poorly Water-Soluble Tadalafil from Amorphous Solid Dispersions Prepared by Various Methods

The aims of this study were to investigate how the release of tadalafil is influenced by two grades of polyvinylpyrrolidone (Kollidon® 12 PF and Kollidon® VA 64) and various methods of preparing solid dispersions (solvent evaporation, spray drying and hot-melt extrusion). Tadalafil is poorly water-soluble and its high melting point makes it very sensitive to the solid dispersion preparation method. Therefore, the objectives were to make a comparative evaluation among different solid dispersions and to assess the effect of the physicochemical nature of solid dispersions on the drug release profile with respect to the erosion-diffusion mechanism. The solid dispersions were evaluated for dissolution profiles, XRD, SEM, FT-IR, DSC, and solubility or stability studies. It was found that tadalafil release was influenced by polymer molecular weight. Therefore, solid dispersions containing Kollidon® 12 PF showed a faster dissolution rate compared to Kollidon® VA 64. Tadalafil was released from solid dispersions containing Kollidon® 12 PF because of the combination of erosion and diffusion mechanisms. The diffusion mechanisms were predominant in the initial phase of the experiment and the slow erosion was dissolution-controlling at the second stage of the dissolution. On the contrary, the tadalafil release rate from solid dispersions containing Kollidon® VA 64 was controlled solely by the erosion mechanism.

Studies on effect of co-processing on palmyrah and maize starch mixtures using DOE approach

Starch mixture is an important approach in designing drug delivery system with modulated properties. The aim of the present work is to study the effect of pregelatinization on starch mixture by varying the concentration of palmyrah and maize starch. All the starch mixtures were statistically designed using 3² full factorial design. Further, the mixtures were characterized for physicochemical and drug release properties. The amylose content, water holding capacity (WHC), swelling and solubility power tend to increase with increase in pregelatinization time. The X-ray diffractogram (XRD) confirmed the reduction in crystallinity of starch mixture with increase in pregelatinization time. The FT-IR study confirmed the gelatinization characteristics of the mixture. All the pregelatinized starch mixture exhibited shear-thinning behavior. Micromeritic property of various starch mixture showed the good flow properties. Formulation with this novel excipient system, using paracetamol as model drug indicated its utility for immediate release dosage form.