Stealth Me. PEG‐PLA Nanoparticles Avoid Uptake by the Mononuclear Phagocytes System

Drug transport to brain with targeted nanoparticles

“…81 Within 5 min, however, ϳ50% (PEG 20000 ) to 75% (PEG 5000 ) of injected nanoparticles (estimated from the blood clearance curves) had been cleared from the blood compartment (compared with 95% with control PLGA nanoparticles). In another study performed in rats, the blood half-lives of [ 14 C]PLA-labeled mPEG-PLA 30,000 nanoparticles with PEG molecular weight of 2000 73 (205 nm diameter) or 5000 78 (140 Ϯ 60 nm) were markedly higher (6 h) and independent of the PEG molecular weights. Less prolonged blood circulation times were observed with PLGA nanoparticles coated with PLA 3000 -PEG 4000 (147 Ϯ 3.6nm) or PLA 3000 -PEG 5000 (161 Ϯ 3.7nm) (T [1/2] ϭ 15 min and T [1/2] ϭ 1 h, respectively, estimations from the blood clearance curves).…”

“…76 Following the rule hydrophobic and negative PLA or PLGA nanoparticle surfaces 57,58 activate the complement system 32 and coagulation factors 77 in vitro. In contrast, hydrophilic coating with PEG sterically stabilizes PLA or PLGA nanoparticles and reduces opsonization and phagocytosis in vitro 32 or ex vivo, 78 and uptake by neutrophilic granulocytes in vivo. 79 Compared with nonpegylated PLA nanoparticles, pegylated nanoparticle surfaces have lower negative potential values, due to the surface shielding by the PEG corona.…”

Impact of PEG and PEG- b -PAGE modified PLGA on nanoparticle formation, protein loading and release

“…PEGylation of PLGA, in order to produce PEG-b-PLGA (PP), also increases the circulation time of the NPs in the human body, as a consequence of passively masking the NPs from the host immune system (Bazile et al, 1995). The next step in the development of a superior PLGA is considered to be the addition of a functional block to PEG-b-PLGA, allowing for the covalent OVA is commonly used as a model antigen/protein in murine animal studies investigating protein drug delivery with hydrophobic micro-or nanoparticles; its use in the current work therefore allowed for comparison of the obtained data to literature (Reddy et al, 2007;Slütter et al, 2009).…”

The role of peptides in blood‐brain barrier nanotechnology

“…Different nanoparticle surface coatings are used for different purposes: hydrophilic surfactants [41,68,[85][86][87] reduce nanoparticle absorption by reticuloendothelial system organs to alter biodistribution of the nanoparticle; poloxamers and poloxamines induce a steric repulsion effect, which minimises adhesion of nanoparticles to macrophage surfaces, consequently minimising phagocytic uptake [88]; surface PEGylation increases blood half-life of nanoparticles [49,89,90]; and polysorbate-80 improves BBB transport of nanoparticles [67,87,91,92]. Any coating used for CNS targeted nanoparticles must allow the interactions needed for BBB transport [88].…”