Ganoderma lucidum polysaccharide loaded sodium alginate micro-particles prepared via electrospraying in controlled deposition environments.

Ganoderma lucidum polysaccharide (GLP) is a functional food source deployed in preventative medicine. However, applications utilizing GLP are limited due to oxidative and acidic environmental damage. Advances in preserving GLP structure (and therefore function), in situ, will diversify their applications within biomedical fields (drug and antibacterial active delivery via the enteral route). In this study, GLP loaded sodium alginate (NaAlg) micro-particles (size range 225-355μm) were generated using the electrospray (ES) process. The loading capacity and encapsulation efficiency of GLP for composite particles (collected at different temperatures) were ∼23% and 71%, respectively. The collection substrate (CaCl2, 1-20w/v%) concentration was explored and preliminary findings indicated a 10w/v% solution to be optimal. The process was further modified by manipulating the collection environment temperature (∼25 to 50°C). Based on this, NaAlg/GLP micro-particles were engineered with variable surface morphologies (porous and crinkled), without effecting the chemical composition of either material (GLP and NaAlg). In-vitro release studies demonstrated pH responsive release rates. Modest release of GLP from micro-particles in simulated gastric fluid (pH ∼1.7) was observed, while rapid release was exhibited under simulated intestinal conditions (pH ∼7.4). Release of GLP from NaAlg beads was the greatest from samples prepared at elevated environmental temperatures. These findings demonstrate a facile route to fabricate GLP-NaAlg loaded micro-particles with various shapes, surface topographies and release characteristics via a one-step ES process.