Oral delivery of near-infrared quantum dot loaded micelles for noninvasive biomedical imaging

ACS Appl Mater Interfaces. 2012 Aug;4(8):3880-7. doi: 10.1021/am301048m. Epub 2012 Aug 10.

Abstract

The purpose of this study is to design, develop, and characterize an optical imaging agent for oral administration. The hydrophobic, nanosized (7 nm), near-infrared (NIR) quantum dots (QDs) have been loaded into deoxycholic acid (DOCA) conjugated low molecular weight heparin (LMWH) micelles. The QD-loaded LMWH-DOCA (Q-LHD) nanoparticles have been characterized by electrophoretic light scattering (ELS) and a transmission electron microscope (TEM) which shows the average particle size was 130-220 nm in diameter. The Q-LHD nanoparticles also show the excellent stability in different pH conditions, and the release profile demonstrates the slow release of QDs after 5 days of oral administration. Concfocal laser microscopic scanning images show that the Q-LHD nanoparticles penetrate the cell membrane and are located inside the cell membrane. The real time pharmacokinetics studies show the absorption, distribution, metabolism, and elimination profile of Q-LHD nanoparticles, observed by the Kodak molecular imaging system (KMIS). This study has demonstrated that the orally administered Q-LHD nanoparticles are absorbed in the small intestine through the bile acid transporter and eliminated through the kidneys.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Biochemistry / methods
  • Caco-2 Cells
  • Cadmium / chemistry
  • Deoxycholic Acid / chemistry
  • Diagnostic Imaging / methods*
  • Female
  • Heparin, Low-Molecular-Weight / chemistry
  • Humans
  • Hydrogen-Ion Concentration
  • Light
  • Mice
  • Mice, Nude
  • Micelles*
  • Microscopy, Electron, Transmission / methods
  • Nanoparticles / chemistry
  • Quantum Dots*
  • Scattering, Radiation
  • Spectroscopy, Near-Infrared / methods

Substances

  • Heparin, Low-Molecular-Weight
  • Micelles
  • Deoxycholic Acid
  • Cadmium