Proficiency of pluronic based niosomes as an effective nano-carrier for the formulation of toll-like receptor-7/8 agonists

Imidazoquinoline (IMDQ) based small molecule TLR7/8 agonists are the immunostimulating agents with potential to be used as vaccine adjuvants . However, these immune-activating molecules have limitations, including poor solubility and side effects due to systemic exposure. To address these inadequacies, efforts are being made to develop efficient delivery systems. In the present study, two niosome formulations of TLR7/8 agonists BBIQ and m -AMBBIQ were prepared: one using PF-68, Tween 80 , and Span 60 , and the other using PF-127, Tween 80, and Span 60, which were analyzed by dynamic light scattering . The optimized niosomal formulation comprising PF-127, Tween 80, and Span 60 excipients was found to be stable with high drug entrapment efficiencies (>90 %). The shape and size of the niosomes were characterized using dynamic light scattering and high-resolution transmission electron microscopy. The interactions between TLR7/8 agonists and the niosome system was studied using Fourier transform infrared spectroscopy . In vitro release studies and kinetic modeling were performed to examine the drug release behavior from the niosomes. In vitro cytotoxicity and hemolytic studies confirmed that the prepared pluronic-based niosomes are safe, efficient, and biocompatible nanocarrier for delivering small molecule TLR7/8 agonists. • Pluronic F-127-based niosomes were prepared for the effective delivery of TLR7/8 agonists BBIQ and m -AMBBIQ. • The prepared niosomes exhibited high encapsulation efficiency (>90 %). • The release kinetics of TLR7/8 agonists-loaded niosomes followed the Weibull model. • The TLR7/8 agonist-loaded niosomes demonstrated no toxicity towards human breast cancer cell lines and were non-hemolytic.