Enhanced pulmonary delivery of insulin by lung lavage fluid and phospholipids

Int J Pharm. 2001 Apr 17;217(1-2):25-31. doi: 10.1016/s0378-5173(01)00588-9.


Pulmonary delivery appears to be the most promising non-parenteral route of insulin administration. In this work, we investigated the enhancement of insulin absorption in the presence of phospholipids and lung lavage fluid in vivo and in vitro. In-vitro experiments of insulin uptake by type II cells showed a significantly enhanced absorption in presence of lavage fluid, compared to various buffer preparations. The same trend was obtained with in-vivo studies of tracheal instillation of insulin. The incorporation of phospholipids as absorption enhancers in 1,2-dipalmitoyl phosphatidylcholine (DPPC) dispersion was compared to blank liposomes. A significantly higher blood glucose decrease was observed with a DPPC-insulin physical mixture compared to liposome, suggesting a possible effect of the phospholipid chain physical state on the insulin in-vivo absorption.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1,2-Dipalmitoylphosphatidylcholine / pharmacokinetics*
  • Animals
  • Blood Glucose / metabolism*
  • Bronchoalveolar Lavage Fluid*
  • Cells, Cultured
  • Hypoglycemic Agents / administration & dosage
  • Hypoglycemic Agents / pharmacokinetics*
  • Insulin / administration & dosage
  • Insulin / pharmacokinetics*
  • Liposomes
  • Lung / metabolism*
  • Male
  • Phospholipids / administration & dosage
  • Phospholipids / pharmacokinetics
  • Rats
  • Rats, Sprague-Dawley


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin
  • Liposomes
  • Phospholipids
  • 1,2-Dipalmitoylphosphatidylcholine