SYMMETRICAL 1,3-DIGLYCERIDES AS SOLID LIPID MICROPARTICLES FOR CONTROLLED DRUG DELIVERY
Solid lipid microparticles (SLM) made from triglycerides and waxes are promising colloidal systems for controlled drug delivery. In this study, new symmetrical 1,3-diglycerides compromised of dihydroxyacetone and lipids of varying chain length were synthesized and used to fabricate solid lipid microparticles via a modified solvent-emulsification evaporation method. Particles were physically characterized in terms of size, surface morphology, surface charge as a function of lipid chain length. Scanning electron micrograph images showed that lipid particles display a distinct surface morphology depending on lipid chain length, with morphology transitions from smooth to porous structures with increasing chain length. Results of zeta potential measurements showed that the spheres are negatively charged and are susceptible to Schiff base reaction or reductive amination reaction with primary and secondary amines such as linear- polyethylenimine on the surface. Hydrophobic (nile red) and hydrophilic (rhodamine-B) model drug compounds were incorporated into the microparticles to determine encapsulation efficiency and in vitro release kinetics. Release kinetics of the hydrophobic compound nile red showed increasing release kinetics with increasing chain length, while microparticles incorporating the hydrophilic compound rhodamine-B exhibited burst release characteristics in all cases. These results outline the initial characterization of dihydroxyacetone-based symmetrical 1,3-diglycerides as new materials for controlled drug delivery.
Controoled drug delivery; Solid lipid microparticles; rhodamine-B; nile red; dihydroxyacetone; 1.3-diglycerides