Roll Compaction/Dry Granulation (Rcdg): Technologies and Their Applications In Drug Delivery and Development

Abstract

Recently molecular modelling, high throughput screening, combinatorial and parallel synthesis techniques have increased the number of drug molecules ready for formulation into suitable delivery systems. However, many of these drugs have poor physicochemical properties. Oral route is the most preferred route of drug administration due to its convenience, highest patient compliance and low production cost. However, formulating drugs having inconsistent low densities, with poor flow properties and compressibility in solid dosage forms poses a major challenge for the formulation scientist. Roll Compaction/Dry Granulation (RCDG) is a pressure agglomeration method in which powder(s) is densified by passing between two counter-rotating rolls. The RCDG technique has significant effect on fluidity, compressibility and compactibility of the pharmaceutical active pharmaceutical ingredients and excipients consequently, influencing drug release profile and tablet properties. There is an increasing interest of industry and academia in RCDG technique, since RCDG excludes any liquid solvent or binder solution and is environmentally safe and cost-effective. Various mathematical models for analysis of powder compaction are reported, that allow better understanding of process parameters, leading to its better design and control. However, losses of tabletability/reworkability, high fines fraction, non-homogeneity of compacts are few challenges in formulation development using roll compaction. These can be overcome by judicious optimization of process parameters and selection of appropriate excipients. This article aims at discussing the current technological advancements related to roll compactor devices available for dry granulation, their working principle, benefits and challenges of RCDG technology along with various applications relevant to the pharmaceutical field.