Microparticle fabricated from a series of symmetrical lipids based on dihydroxyacetone form textured architectures

Abstract

We report the synthesis of a series of symmetrical lipids composed of dihydroxyacetone and even‑carbon fatty acids (eight to sixteen carbons), both components of the human metabolome, and characterize their formulation into porous microparticles through spontaneous emulsification without the use of additional porogens. Lipid hydrolysis products were identified by ¹H NMR to validate lipid degradation into the parent metabolic synthons. Microparticle architecture, as determined by scanning electron microscopy, was lipid-length dependent, with shorter alkyl chains forming tight structures and longer alkyl chains forming larger pores with plate-like lipid architectures. In all cases, the lipids formed organized patterns, not irregular shapes. As a demonstration of the potential use of these solid lipid-based microparticles, the release kinetics of a model drug (piroxicam) was quantified showing that release was more greatly influenced by microparticle porosity, and hence surface area, than by hydrophobicity of the lipids.

Keywords: Controlled release; Dihydroxyacetone; Metabolic synthons; Porous microparticles; Spontaneous emulsification.