Background: The treatment of schizophrenia typically involves the use of olanzapine (OLZ), a typical antipsychotic drug that has poor oral bioavailability due to its low solubility and first-pass effect. Objective: To prepare and optimize OLZ as nanoparticles for transdermal delivery to avoid problems with oral administration. Methods: The nanoprecipitation technique was applied for the preparation of eight OLZ nanoparticles by using different polymers with various ratios. Nanoparticles were evaluated using different methods, including particle size, polydispersity index (PDI), entrapment efficiency (EE%), zeta potential and an in vitro release study. The morphology was evaluated by a field emission scanning electron microscope (FESEM) and an atomic force microscope (AFM). We also perform differential scanning calorimetry (DSC). Results: Characterization studies of OLZ nanoparticles showed that OLZ-6 was the best formula with a particle size of 115.76 nm, a PDI of 0.24, a high EE% of 78.4%, and a high zeta potential of -19.01 mV. The in vitro release of OLZ was higher than that of other formulations. FESEM reveals the spherical shape of the nanoparticles, and AFM screening confirms that the OLZ-6 size is comparable to what the Zeta sizer finds. The DSC results confirm the purity of OLZ and the compatibility between the drug and polymer. Conclusions: OLZ-6, as a transdermal delivery system, is a promising formula to overcome the problems associated with oral drug administration and could enhance its bioavailability.
