PEG–PLGA based large porous particles for pulmonary delivery of a highly soluble drug, low molecular weight heparin

Preparation and In Vitro Evaluation of Biodegradable Microspheres with Narrow Size Distribution for Pulmonary Delivery

“…mPEG-PLGA microspheres prepared by only double emulsion method was obtained according to the literature [25] . The same procedure was carried out to form the primary emulsion (W1/O) as mentioned above.…”

“…To study the in vitro release pattern of encapsulated BSA from the microspheres, 100 mg freeze-dried microspheres was suspended in 20 ml simulated lung fluid (SLF), prepared according to Moss formula plus 0.1 % Tween 80 at pH 7.4 and stirred at 60 rpm at 37±1°[ 25,32,33] . An aliquot of samples (800 μl) was withdrawn following centrifugation over a period of 28 d at various time intervals.…”

Low-Molecular-Weight Heparin (LMWH)–Loaded Large Porous PEG-PLGA Particles for the Treatment of Asthma

“…(18) In this study, we have used an optimized formulation prepared with PEG-PLGA diblock copolymers and 8% sodium chloride in the external aqueous phase. In the published study, we evaluated the respirability of this particular formulation in detail.…”

“…Particle characterization and optimization have been reported in a previous publication. (18) We and others have shown that large porous particles with relatively low density exhibit favorable aerodynamic behavior and improved deposition efficiency in the lungs. Further, sustained release of LMWH from the particles provides greater concentrations of drug in the lungs and thus an increase in the duration of activity.…”

“…(7,11,17) We and others have developed drug delivery systems for inhalational delivery of heparin. (18,19) The goal of the formulation-based approaches was to produce a continuous release of the drug in the lung and reduce bleeding complications associated with systemic exposure. For example, heparin encapsulated in chitosan nanoparticles (20,21) and inhalable poly(D,L-lactideco-glycolide) (PLGA) microparticles (12) is shown to be efficacious in the treatment of asthma and other inflammatory conditions.…”