Hydrophobically Modified Cellulose Nanofibers-Enveloped Solid Lipid Microparticles for Improved Antioxidant Cargo Retention

This study introduces a cellulose nanofiber surfactant system, in which the surface is hydrophobically modified with different alkyl chain structures for the effective envelopment of solid lipid microparticles (SLMs). To endow bacterial cellulose nanofibers (BCNFs) with excellent ability to assemble at the lipid-water interface, alkyl chains with designated molecular structures, such as decane, didecane, and eicosane, are covalently grafted onto the BCNF surface. Interfacial tension and interfacial rheology measurements indicate that dialkyl chain-grafted BCNFs (diC(10)BCNF) exhibit strong interfibrillar association at the interface. The formation of a dense and tough fibrillary membrane contributes significantly to the enveloping of the SLMs, regardless of the lipid type. Because the diC(10)BCNF-enveloped SLMs exhibit a core molecular crystalline phase at the microscale, they can immobilize an oil-soluble antioxidant while maintaining its long-term storage stability. These findings show that the cellulose-surfactant-based SLM technology is applicable to the stabilization and formulation of readily denatured active ingredients.

Automated summary

This study introduces a cellulose nanofiber surfactant system that effectively envelops solid lipid microparticles (SLMs) by modifying the fiber surface with different alkyl chain structures. The research shows that alkyl chains with specific molecular structures can facilitate the assembly of cellulose nanofibers at the lipid-water interface, resulting in the formation of a dense and tough fibrillary membrane that envelopes the SLMs. Furthermore, this technology enables the immobilization of oil-soluble antioxidants while maintaining their long-term storage stability.