title: Preparation, characterization and pharmacokinetics of enrofloxacin-loaded solid lipid nanoparticles: influences of fatty acids.
abstract: Enrofloxacin-loaded solid lipid nanoparticles (SLN) were prepared using fatty acids (tetradecanoic acid, palmitic acid, stearic acid) as lipid matrix by hot homogenization and ultrasonication method. The effect of fatty acids on the characteristics and pharmacokinetics of the SLN were investigated. The results showed that the encapsulation efficiency and loading capacity of nanoparticles varied with fatty acids in the order of stearic acid>palmitic acid>tetradecanoic acid. Furthermore, stearic acid-SLN had larger particle size, bigger polydispersity index (PDI) and higher zeta potential compared with the other two fatty acid formulated SLN. The SLN showed sustained releases in vitro and the released enrofloxacin had the same antibacterial activity as that of the native enrofloxacin. Although in vitro release exhibited similar patterns, within 24 h the releasing rates of the three formulations were significantly different (tetradecanoic acid-SLN>palmitic acid-SLN>stearic acid-SLN). Pharmacokinetic study after a single dose of intramuscular administration to mice demonstrated that tetradecanoic acid-SLN, palmitic acid-SLN, and stearic acid-SLN increased the bioavailability by 6.79, 3.56 and 2.39 folds, and extended the mean residence time (MRT) of the drug from 10.60 h to 180.36, 46.26 and 19.09 h, respectively. These results suggest that the enrofloxacin-fatty acid SLN are promising formulations for sustained release while fatty acids had significant influences on the characteristics and performances of the SLN.
authors.affiliation: Department of Preventive Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, 2 Yuanmingyuan Road West, Beijing 100193, PR China.
authors.forename: Shuyu
authors.initials: S
authors.lastname: Xie
authors.forename: Luyan
authors.initials: L
authors.lastname: Zhu
authors.forename: Zhao
authors.initials: Z
authors.lastname: Dong
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Xihe
authors.initials: X
authors.lastname: Li
authors.forename: WenZhong
authors.initials: W
authors.lastname: Zhou
mesh_terms: D000077422:Enrofloxacin; D005227:Fatty Acids / Q000737:chemistry*; D024841:Fluoroquinolones / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics*; D008055:Lipids / Q000138:chemical synthesis / Q000737:chemistry / Q000493:pharmacokinetics*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D005227:Fatty Acids; D024841:Fluoroquinolones; D008055:Lipids; D000077422:Enrofloxacin