Preparation of Drug Delivery Biodegradable PLGA Nanocomposites and Foams by Supercritical COsub2 Expanded Ring Opening Polymerization and by Rapid Expansion from CHCIF2 Supercritical Solutions
Abstract
The synthesis of poly(lactic-co-glycolic acid) (PLGA) by the ring opening copolymerization of D,L-lactide and glycolide was performed at 110 deg C to 130 deg C using Sn(Oct)2 as catalyst, 1,10-decanediol as initiator in a supercritical sc-CO2 expanded medium at pressures of up to 2,500 psi. Due to the limited monomer solubility in sc-CO2 at low temperatures (70 deg C), only Mn=2,500 is typically obtained. However, molecular weight increases with both temperature and sc-CO2 pressure. Thus, Mn = 13,000 (PDI = 1.28) was obtained at 110 deg C - 130 deg C even in the absence of fluorinated surfactants. Biodegradable drug delivery nanocomposites based on dexamthasone and poly(lactic acid) (PLA) and poly(lactide-co-glycolide) (PLGA) were prepared by the rapid expansion of the corresponding supercritical CHCIF2 solutions (110 deg C, 200-300 bar) in air (RESS) and in toluene (RESOLV). The RESS process leads to a broad particle size distribution (100-500 nm) while the RESOLV generates a narrower distribution centered around 100 nm and is accompanied by the formation of a few large particles, most likely due to aggregation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2005
- Accession Number
- ADP019727
Entities
People
- Alexandru D. Asandei
- Banu S. Zolnik
- Can Erkey
- Carl Saquing
- Diane J. Burgess
- Gobinda Saha
Organizations
- University of Connecticut