Preparation, characterization and in vivo distribution of solid lipid nanoparticles loaded with syringopicroside.

A solvent emulsification evaporation method was employed to prepare solid lipid nanoparticles (SLN) loaded with syringopicroside. The conventional broad-spectrum antibacterial and antiviral drug syringopicroside was incorporated into SLN to improve drug targeting. The SYR-SLNs were spherical and uniform in transmission electron microscopy (TEM). The mean particle size and potential were 180.31 +/- 10 nm, and -41.9 +/- 10.3 mV, respectively. Also, a sephadex column chromatography was adopted to investigate the encapsulation efficiency (EE %) of the SLN. This method is based on the principle of molecular sieve effect, and the EE% of the optimal formulation was 42.35 %. Drug-loading capacity was 5.33 %. The in vitro release profile revealed that syringopicroside was released from SLN efficiently and completely in normal saline (NS) compared with other release media. A HPLC method was established for in vivo assay of syringopicroside. A tissue distribution study was conducted in rats after iv administration of 15 mg/kg SYR-SLN and syringopicroside NS, and it was found that SYR-SLN has improved delivery to the liver compared with any other organizations. These results indicated that solvent emulsification evaporation is a simple, easy, available and effective method for preparing SYR-SLN.