PolySciTech (
www.polyscitech.com)
provides a wide array of biodegradable block copolymers including PLA-PEG-PLA
triblock copolymers at a variety of MW’s and chiral characteristics. Recent
research utilizing Dissipative Particle Dynamic simulations back by laboratory
experimental results have honed in on the optimal PEG to PLA ratio for forming
a micelle for drug delivery. Read more: Chansuna, Mantana, and Nuttaporn
Pimpha. "Mesoscale simulation and experimental studies of self-assembly
behavior of a PLA-PEG-PLA triblock copolymer micelle for sustained drug
delivery." Journal of Polymer Research 21, no. 6 (2014): 1-9. http://link.springer.com/article/10.1007/s10965-014-0452-1
“Abstract: Dissipative Particle Dynamic simulation
(DPD) was employed to investigate PLA-PEG-PLA copolymer micelles to gain more
understanding at the molecular level in addition to experimental studies.
Critical micelle concentration (cmc), micelle size and small molecule
encapsulation of these triblock copolymer micelles with different
hydrophobic/hydrophilic (LA/EG) block ratios (2.56, 4.88 and 7.25 with fixed
PEG length = 23 monomer units) were determined. Only the appropriated LA/EG
block ratio (4.88 and 7.25) can induce the formation of spherical micelle in a
dilute solution. The cmc and micelle size were decreased and increased,
respectively, as a function of the LA/EG block ratio. Upon adding small
solubilizate molecules, a larger micelle size was formed. Then, PLA-PEG-PLA
with the same LA/EG block ratios as DPD simulation were synthesized and the
micelle solution was prepared. Pyrene was used as the molecular probe to find
the cmc by fluorescence spectroscopy. Light scattering was applied to determine
the hydrodynamic radius (R H ) of these micelles. The cmc and RH were decreased
and increased, respectively, with LA/EG ratio, qualitatively similar to the
trends as simulation results. The behavior of these copolymer micelles to
encapsulate the small solubilizate molecules was also studied by fluorescence
technique. The partition coefficients of pyrene between the water phase and the
micelle core were increased with a higher LA/EG block ratio similar to results
from the simulation. Keywords: Triblock copolymer, Micelle, Mesoscale
simulation, Drug delivery”
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