Formulation, optimization and full characterization of mirtazapine loaded aquasomes: a new technique to boost antidepressant effects.

Objective: The development of Mirtazapine (MRT)-loaded aquasomes by co-precipitation sonication technique to boost the antidepressant potential of MRT.

Methodology: MRT-loaded aquasomes formulations were prepared using Box-Behnken design to investigate the effect of independent factors including sonication time (X1), sonication temperature (X2), and sugar concentration (X3) on the dependent variables as particle size and drug loading efficiency. The formulation of the optimized formula was verified by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and X-ray Powder Diffraction (XRPD). Furthermore, the morphology of the formula was evaluated by Transmission Electron Microscopy (TEM). The optimum MRT- loaded aquasomes was assessed for physiochemical properties, in vitro MRT release and in vivo antidepressant effects in mice model.

Results: The results revealed that the optimized formula showed a small particle size of 202.7 ± 3.7 nm and a high loading efficiency of 77.65 ± 2.6%. Thermal DSC and XRPD studies demonstrated the amorphous nature of MRT-loaded aquasomes. The in vitro study demonstrated sustained release of F (opt) 88.16% after 8 h, compared with plain MRT release of 63.06% after 1 h. Mice treated with MRT-loaded aquasomes demonstrated reduced immobility time in behavioral analysis to 37% with MRT-loaded aquasomes, while plain MRT reduced it to 55%.

Conclusion: These results confirmed that the antidepressant effect of MRT was significantly boosted in formulated aquasomes, and thereby they provide a promising carrier nano vesicular system for effective delivery of MRT.