Performance of alkyl β-D-maltosides in molecular self-assembly and formation of oil-in-water nanoemulsions as drug delivery systems

Abstract

Alkyl β-D-maltosides are nonionic sugar-based surfactants that can be used as excipients in lipid-based nanoparticles because of their physiological functions and biocompatibility. The self-assembly of alkyl β-D-maltosides (C8-C12) was studied to investigate the effects of alkyl chain length in the binary and ternary systems. Surface tension measurements in the binary systems revealed a synergistic effect on the stability of mixed surfactants with Tween 80 (T80) in the critical aggregation concentration (CAC). Subsequently, formulations of 10:90 wt% oil-in-water (O/W) nanoemulsions (ternary systems) containing T80/alkyl β-D-maltosides with and without cyclosporine (CsA) as the hydrophobic model drug were characterised by particle size, polydispersity index (PDI), morphology, rheology, and physical stability. The formulations of all nanoemulsion systems were found to be stable against phase separation for 28 days at room temperature. The hydrophobic effect of n-dodecyl-β-D-maltoside (DDM, C12) was stronger by enhancing the stability of T80 nanoemulsion in molecular self-assembly compared to the shorter chains of the maltosides. The in vitro drug release study showed that T80/DDM nanoemulsion improved the cumulative release of CsA in 24 h by 98.33 ± 7.72% compared to T80 nanoemulsion at 83.75 ± 4.05%. The release of CsA has the highest fit with the Korsmeyer-Peppas kinetic model (R2 > 0.9), suggesting that CsA is released slowly from the oily core of nanoemulsions to the dissolution medium due to its hydrophobic nature. The cytotoxicity study against 3T3 cells showed that all formulations had no cytotoxicity effect (IC50) up to 500 μg/mL. The findings demonstrated that T80/DDM nanoemulsion holds great promise as a drug delivery system for the treatment of psoriasis.