MAL(70%)-PEG2000-b-PLA2000 (Maleimide(70%) Polyethylene Glycol Polylactide block copolymer, PEG MW 2000, PLA MW 2000);
MAL(70%)-PEG5000-b-PLA20000 (Maleimide(70%) Polyethylene Glycol Polylactide block copolymer, PEG MW 5000, PLA MW 20000);
Photo provided by Flickr
The nanoprecipitation method employed here yields PLGA nanoparticles with surface decorated with PEG. The incorporation of phospholipid provides additional stability to the nanoparticles in the hydrophilic environment. The surfactant used in the single emulsion method like polyvinyl alcohol renders a high negative charge on the nanoparticles which when administered systemically is rapidly opsonized by the RES system. During the emulsion formation the hydrophobic segments of PVA penetrate into the organic phase and remain entrapped into the polymeric matrix of the nanoparticles which ultimately binds on the particle surface when the organic solvent was removed from the interface [–]. The presence of PEG not only neutralizes the negative charge but also evades the RES system due to its stealth properties . Based on the hydrophobic and hydrophilic interactions in the reaction mixture, represents the structure of PEGylated nanoparticles.
PLGA-PEG Nanoparticle Synthesis - ResearchGate
Photo provided by Flickr
In this study, we hypothesized that PEG-PLGA nanocarrier systems could increase the circulation half-life of endostar by exploiting the enhanced permeation retention phenomenon effectively, and thus increase the effect of the drug.
PCL, PLA, PLGA Polymers and Copolymers : ..
The PC3 and HeLa cells were dispensed into a 96-well flat-bottom microtiter plate (~10,000 cells/well) and allowed to attach overnight using the respective F-12 and DMEM medium with 10 % FBS. The MTS assay was carried out as per manufacturer’s instructions (PROMEGA). It is based on the absorbance of formazan (produced by the cleavage of MTS by dehydrogenases in living cells), the amount of which is directly proportional to the number of live cells. In brief, after 24 hrs and 48 hrs treatments with the Dox loaded PLGA nanoparticles, media was changed and 150 μL of MTS reagent was added to each well. The absorbance of the mixtures at 490 nm was measured after 4 hrs incubation with the MTS reagent. The cell viability was calculated as the ratio of the absorbance of the sample well to that of the control well and expressed as a percentage. Tests were performed in quadruplicate. Each point represents the mean ±SD (bars) of replicates from one representative experiment.
Bone Regeneration from PLGA Micro-Nanoparticles
Since the core of the PLGA is hydrophobic we assume the addition of amphiphilic phospholipid like DPPE-PEG would result in such an alignment that the hydrophobic lipid part incorporates inside the hydrophobic pockets of the PLGA matrix with hydrophilic PEG protruding out for interaction with the aqueous environment. Also the presence of PEG on the surface will embed the excess PVA which remains at the nanoparticles surface. The surface charge of the PEGylated PLGA as measured by the zeta potential studies was −14.17±0.54.