Systematic Study of the Effects of High Shear Granulation Parameters on Process Yield, Granule Size, and Shape by Dynamic Image Analysis

Evaluation of different techniques for wet granulation and pelletization processes using milk as innovative pharmaceutical excipient for pediatric use

The present study focused on the use of milk as a novel excipient for the manufacture of pharmaceutical dosage forms specifically designed for the pediatric population. Dairy milks with different fat contents were studied to deliver paracetamol orally. The World Health Organization included milk in the list of GRAS (generally recognized as safe) substances, which together with its taste-masking ability and solubility solving properties, makes it a good candidate as an excipient in formulations containing paracetamol for pediatrics. The influence of the fat content in the milk, the fraction of paracetamol, the type of diluent and drying temperature (considered independent variables) were systematically investigated using a Design of Experiments (DoE) approach for the preparation of granules for oral administration, by wet agglomeration using different processing techniques, enabled the construction of mathematical models reflecting the correlation between the variables. Four different techniques were evaluated: wet granulation by low shear mixer, wet granulation by high shear mixer, wet granulation by fluidized bed, and extrusion and spheronization. The granules and pellets obtained were characterized for size, and size distribution of agglomerates, and complete release of the drug (dependent variables), according to the European Pharmacopoeia. The fraction of fat content in the milk promoted an increase on the dissolution rate of paracetamol. The key finding of the first two process techniques was a migration of paracetamol from powdered agglomerates towards the larger particles, probably due to friction and attrition events, which created a fraction of smaller size granules due to the fragmentation and loss of powder from the larger granules. The study has confirmed the potential of milk to be a novel and efficient excipient that can be used as a liquid binder in various agglomeration techniques to deliver drugs orally.

Chitosan and Sodium Alginate Implementation as Pharmaceutical Excipients in Multiple-Unit Particulate Systems

This study aimed to prepare and evaluate pellets containing acyclovir as a model drug. Pellets were prepared by the extrusion–spheronization process. Aqueous solutions of natural marine polymers (sodium alginate, chitosan) were compared to semi-synthetic hydroxypropyl methylcellulose (HPMC) in the role of binders. The study focused on the characterization of the pellet properties that are crucial for the formulation of the final dosage form, such as in multi-unit pellet system (MUPS) tablets or hard gelatin capsules filled with the pellets. Finally, the mentioned dosage forms were tested for drug dissolution. The morphology of pellets observed by scanning electron microscopy correlated with the shape evaluation performed by dynamic image analysis. Sodium alginate pellets exhibited the lowest value of sphericity (0.93), and many elongated rods and dumbbells were observed in this batch. Chitosan pellets had the highest value of sphericity (0.97) and were also less rough on the surface. The pellets maintained a constant surface geometry during the dissolution studies; they only reduced in size. The most significant reduction in size and weight was assessed after 2 h of dissolution testing. This fact was in line with the drug release from pellets in capsules or MUPS tablets, which was massive during the first hour, in both cases. The dissolution profiles of all of the batches were comparable.