Preparation and evaluation of Baicalin-loaded cationic solid lipid nanoparticles conjugated with OX26 for improved delivery across the BBB.

PURPOSE: A novel brain targeting drug delivery system based on OX26 antibody conjugation on PEGylated cationic solid lipid nanoparticles (OX26-PEG-CSLN) was prepared. METHODS: The Baicalin-loaded PEGylated cationic solid lipid nanoparticles modified by OX26 antibody (OX26-PEG-CSLN) were prepared by emulsion evaporation-solidification at low temperature method. The immune-gold labeled OX26-PEG-CSLN was visualized by transmission electron microscopy. The mean diameter and zeta potential of OX26-PEG-CSLN, PEG-CSLN and CSLN were determined using a Zetasizer. The entrapment efficiency of OX26-PEG-CSLN, PEG-CSLN and CSLN was determined by ultrafiltration centrifugation method. And the solid-state characterization of OX26-PEG-CSLN and CSLN were analyzed by X-ray. Pharmacokinetics studies were conducted by in vivo microdialysis in rat cerebrospinal fluid. RESULTS: The results showed that the OX26-PEG-CSLN, PEG-CSLN and CSLN had average diameters of 47.68 ± 1.65, 27.20 ± 1.70 and 33.89 ± 5.74 nm, Zeta potentials of -0.533 ± 0.115 mV, 11.200 ± 0.500 mV and 11.080 ± 1.170 mV and entrapment efficiencies of 83.03 ± 0.01%, 92.90 ± 3.50% and 97.83 ± 0.19%, respectively. In the pharmacokinetics studies, the AUC value of OX26-PEG-CSLN was11.08-fold higher than that of the Baicalin solution (SOL) (p<0.01), and 1.12-fold higher than that of the CSLN (p>0.05); the Cmax value of OX26-PEG-CSLN was 7.88-fold higher than that of SOL (p<0.01) and 1.12-fold (p<0.01) higher than that of the CSLN, respectively. CONCLUSION: These results demonstrated OX26-PEG-CSLN could be a promising carrier to deliver drugs across the BBB for the treatment of brain diseases.