The influence of lung surfactant liquid crystalline nanostructures on respiratory drug delivery.
The respiratory route increasingly has been used for both local and systemic drug delivery. Although drug is absorbed rapidly after respiratory delivery, the role of lung surfactant in drug delivery is not well understood. The human lung contains only around 15mL of surface lining fluid spread over ∼100m2surface. The fluid contains lung surfactant at a concentration of 8-24mg/kg/body weight; the lung surfactant which is lipo-protein in nature can form different liquid crystalline nanostructures. After a brief overview of the anatomy of respiratory system, the review has focused on the current understanding of lung surface lining fluid, lung surfactants and their composition and possible self-assembled nanostructures. The role of lung surfactant in drug delivery and drug dissolution has been briefly considered. Lung surfactant may form different liquid crystalline phases which can have an active role in drug delivery. The hypotheses developed in this review focuses on the potential roles of surface epithelial fluid containing liquid crystalline nanostructures in defining the dissolution mechanism and rate. The hypotheses also focus an understanding how liquid crystalline nanostructures can be used to control dissolution rate and how the nanostructures might be changed to influence delivery and induce toxicity.
New Zealand's National School of Pharmacy, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand. Electronic address: shyamal.das@otago.ac.nz.
Shyamal C
SC
Das
Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia.
Peter J
PJ
Stewart
D065546:Drug Liberation; D006801:Humans; D050866:Liquid Crystals / Q000737:chemistry*; D008168:Lung / Q000033:anatomy & histology / Q000378:metabolism*; D008954:Models, Biological; D049329:Nanostructures / Q000737:chemistry*; D011663:Pulmonary Surfactants / Q000737:chemistry / Q000378:metabolism; D065589:Respiratory Tract Absorption
D011663:Pulmonary Surfactants
Absorption; Controlled release; Dissolution; Liquid crystal; Lung surfactant; Respiratory drug delivery