A Review on the Preparation and Characterization of Sodium Alginates Beads

Sodium alginate beads are widely used polymeric delivery systems formed through ionic gelation of sodium alginate with multivalent cations, commonly calcium ions. These beads have gained significant attention in pharmaceutical, biomedical, food, and biotechnology applications due to their biocompatibility, biodegradability, non-toxicity, and mild preparation conditions. The gel network produced during cross-linking enables effective encapsulation of drugs, probiotics, enzymes, and bioactive compounds, protecting them from environmental degradation and allowing controlled or sustained release. The physicochemical properties of sodium alginate beads including size, porosity, mechanical strength, and swelling behaviour can be modified by adjusting alginate concentration, crosslinking ion concentration, curing time, and preparation techniques.1 Such tenability makes them suitable for targeted drug delivery, wound healing formulations, tissue engineering scaffolds, and encapsulation of sensitivebiomolecules. Despite several advantages, limitations such as burst release, low mechanical stability under certain conditions, and sensitivity to pH variations remain challenges that require formulation optimization. Overall, sodium alginate bead technology represents a versatile and cost-effective platform for controlled delivery and encapsulation applications across pharmaceutical and industrial fields.2