Brain targeting of venlafaxine HCl as a hydrophilic agent prepared through green lipid nanotechnology

Abstract This study aimed to improve venlafaxine HCl brain delivery using solid lipid nanoparticles (SLNs) made by an ultrasonication method. The impact of the ratio of two surfactants (Tween:Span) on nanoparticle behaviors and their efficiency was examined to achieve optimal brain delivery for venlafaxine. To study the solid-state of venlafaxine in SLNs and detect any potential interactions between the drug and other formulation excipients, PCS, TEM, ATR-FTIR, and DSC were employed. By reducing the HLB (Hydrophilic–lipophilic balance) of the binary surfactants, the particle size of SLN increased. The optimized nanoparticles showed an average particle size of 311.33 ± 9.29 nm when the HLB of the ratio of the surfactants (Tween:Span) was adjusted to 8. The zeta potential of SLNs decreased from −15.90 ± 0.70 to −6.95 ± 0.42 mV when the HLB of the system was reduced from 14 to 8. According to the results, the highest entrapment efficiency of 76.05 ± 1.42% was observed for the formulation with the largest particle size and the lowest HLB value (HLB 8). DSC analysis showed that venlafaxine was in an amorphous state in SLN. The findings of the ATR-FTIR also excluded any chemical interactions between excipients and the drug. Venlafaxine-SLN had a prolonged release pattern, according to the in vitro diffusion process. Venlafaxine oral absorption from SLN was also substantially higher than venlafaxine solution after single-dose oral administration of venlafaxine preparations. This research demonstrated that the venlafaxine-SLN might be employed as a potential nano-vehicle for venlafaxine brain delivery and potentially opens up new avenues for depression treatment.