title: Preparation of a nanoscale baohuoside I-phospholipid complex and determination of its absorption: in vivo and in vitro evaluations.
abstract: BACKGROUND
  Baohuoside I is a potential anticancer drug for a variety of malignancies and has been approved for in vitro use. However, baohuoside I has very poor oral absorption.
  
  
  METHODS
  In the present study, we prepared baohuoside I-phospholipid complexes of different diameters and determined their physicochemical properties using transmission electron microscopy, ultraviolet spectroscopy, and differential scanning calorimetry. The in vitro absorption of baohuoside I and baohuoside I-phospholipid complexes of different sizes were compared using the Caco-2 cell culture model, and subsequently, the bioavailability of baohuosidel and its complexes were estimated in vivo.
  
  
  RESULTS
  Compared with the large-sized phospholipid complexes, a nanoscale phospholipid complex improved the oral bioavailability of baohuoside I. In addition, our results suggest that the smaller the particle size, the faster the complexes crossed the Caco-2 monolayer and the faster they were resorbed after oral administration in rats. The relative oral bioavailability of a nanoscale size 81 ± 10 nm baohuoside I-phospholipid complex (area under the concentration-time curve [AUC](0-∞)) was 342%, while that of baohuoside I and a 227.3 ± 65.2 μm baohuoside I-phospholipid complex was 165%.
  
  
  CONCLUSIONS
  We enhanced the oral bioavailability of baohuoside I by reducing the particle size of the phospholipid complex to the nanometer range, thereby improving its potential for clinical application.
authors.affiliation: Key Laboratory of New Drug Delivery System of Chinese Materia Medica, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Jin
authors.forename: Zhen-hai
authors.initials: ZH
authors.lastname: Zhang
authors.forename: E
authors.initials: E
authors.lastname: Sun
authors.forename: Qian
authors.initials: Q
authors.lastname: Qian
authors.forename: Xiao-bin
authors.initials: XB
authors.lastname: Tan
authors.forename: Xiao-bin
authors.initials: XB
authors.lastname: Jia
mesh_terms: D000042:Absorption; D000284:Administration, Oral; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000737:chemistry; D018938:Caco-2 Cells; D004058:Diffusion; D005419:Flavonoids / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008422:Materials Testing; D008657:Metabolic Clearance Rate; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D009928:Organ Specificity; D010743:Phospholipids / Q000737:chemistry*; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
chemical_list: D000970:Antineoplastic Agents; D005419:Flavonoids; D053769:Nanocapsules; D010743:Phospholipids; C060988:baohuoside I