Swallowing a cellular automaton pill: predicting drug release from a matrix tablet

TL;DR

This paper presents a cellular automaton model to simulate drug release from matrix tablets, accurately reproducing experimental profiles and aiding in formulation optimization.

Contribution

The authors develop a novel CA model that incorporates dissolution, diffusion, fracture, and polymer melting to predict drug release from matrix tablets.

Findings

Simulations match experimental drug release profiles

Model captures effects of tablet fracture and polymer melting

Tool can streamline sustained release tablet formulation

Abstract

Matrix tablets are drug delivery devices designed to release a drug in a controlled manner over an extended period of time. We develop a cellular automaton (CA) model for the dissolution and release of a water-soluble drug and excipient from a matrix tablet of water-insoluble polymer. Cells of the CA are occupied by drug, excipient, water or polymer and the CA updating rules simulate the dissolution of drug and excipient and the subsequent diffusion of the dissolved substances. In addition we simulate the possible fracture of brittle drug and excipient powders during the tablet compression and the melting of the polymer during a possible thermal curing process. Different stirring mechanisms that facilitate the transport of dissolved drug in the fluid in which the tablet is immersed are modeled in the water cells adjacent to the boundary of the tablet. We find that our simulations can reproduce experimental drug release profiles. Our simulation tool can be used to streamline the formulation and production of sustained release tablets.