Purpose: To prepare and characterize polisorbate 80 coated lipid nanoparticles for brain delivery containing loperamide as model drug. Methods: Lipid nanoparticles (LNs) were prepared using hot high pressure homogenization method (65°C, 150000 KPa, 7 homogenization cycles). Cetyl palmitate was chosen as matrix material, while polisorbate 80 was used as emulsion stabilizer. Loperamide (Lop) was encapsulated (3% w/w) as a model drug. The obtained LNs were characterized for their process yield, drug content, dimensions (photon correlation spectroscopy), morphology (transmission electron microscopy, TEM), thermal behavior (differential scanning calorimetry) and physical stability. Preliminary biocompatibility studies were performed on chick embryos using the chorioallantoic membrane (CAM) assay. Results: Blank LNs, prepared in replicate of four to assess method reproducibility, showed a mean diameter of 185 +/- 8 nm with a method yield of around 92 %. LNs were stable at 4°C for a one year period. Lop was embedded with an encapsulation efficiency of about 70%, corresponding to 2.3% of drug content. The encapsulation of the model drug did not influence significantly particle size and distribution (185 +/- 5 nm) that remained unchanged for 5 months. TEM analysis evidenced a similar morphology for blank and loaded LNs. CAM assay evidenced a high biocompatibility of the carrier. In fact, LNs did not stimulate inflammatory reaction as well as angiogenic process. Conclusion: Lop was successfully encapsulated within cetyl palmitate LNs with a good encapsulation efficiency. Particle characteristics and biocompatibility are very promising for brain targeting application.
Colloidal dispersions for targeted brain drug delivery
BLASI, PAOLO;SCHOUBBEN, Aurelie Marie Madeleine;GIOVAGNOLI, Stefano;BARBERINI, Lanfranco;CIROTTO, Carlo;ROSSI, Carlo;RICCI, Maurizio
2009
Abstract
Purpose: To prepare and characterize polisorbate 80 coated lipid nanoparticles for brain delivery containing loperamide as model drug. Methods: Lipid nanoparticles (LNs) were prepared using hot high pressure homogenization method (65°C, 150000 KPa, 7 homogenization cycles). Cetyl palmitate was chosen as matrix material, while polisorbate 80 was used as emulsion stabilizer. Loperamide (Lop) was encapsulated (3% w/w) as a model drug. The obtained LNs were characterized for their process yield, drug content, dimensions (photon correlation spectroscopy), morphology (transmission electron microscopy, TEM), thermal behavior (differential scanning calorimetry) and physical stability. Preliminary biocompatibility studies were performed on chick embryos using the chorioallantoic membrane (CAM) assay. Results: Blank LNs, prepared in replicate of four to assess method reproducibility, showed a mean diameter of 185 +/- 8 nm with a method yield of around 92 %. LNs were stable at 4°C for a one year period. Lop was embedded with an encapsulation efficiency of about 70%, corresponding to 2.3% of drug content. The encapsulation of the model drug did not influence significantly particle size and distribution (185 +/- 5 nm) that remained unchanged for 5 months. TEM analysis evidenced a similar morphology for blank and loaded LNs. CAM assay evidenced a high biocompatibility of the carrier. In fact, LNs did not stimulate inflammatory reaction as well as angiogenic process. Conclusion: Lop was successfully encapsulated within cetyl palmitate LNs with a good encapsulation efficiency. Particle characteristics and biocompatibility are very promising for brain targeting application.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
