Functional cellulose-based beads for drug delivery: Preparation, functionalization, and applications

In pharmaceutical technology, maintaining and controlling the rate of drug release is essential to ensure optimal therapeutic effects, consistent dosage, sustained release, and compliance with treatment by the patient. Cellulose-based beads have distinctive features that include biodegradability, biocompatibility, safety, cost performance, and stability under varying conditions, particularly humidity, pH, and temperature changes. Additionally, due to their versatility, they can be easily functionalized using a range of chemical groups to control the release of drugs and better target particular tissues. Moreover, the porous structure of cellulose-based beads ensures sustained drug release for an extended period. This review deals with producing functional beads from cellulose and its derivatives, which offer the potential to be used as a drug delivery system. In the first part of the review, we present the present knowledge on the extraction methods and properties of cellulose, its different morphological forms, and its applications in drug delivery. In the second part, we discuss the methods of production of cellulose beads production methods, including dissolution/regeneration and simple mechanical process along with their functionalization routes. The last part of the paper focuses on the use of cellulose-based beads as carriers for drug delivery applications, with a focus on the approaches used to load the beads with drugs, and the mechanism of drug release as well as the controlled release.