Preparation, characterization and Calu-3 cellular uptake of three kinds of poly(b-benzyl-L-amino)block-poly(ethylene glycol) nanoparticles

The aim of this paper is to compare the cytotoxicity and cellular uptake efficiency of three kinds of poly(b-benzyl-L-amino) block-poly(ethylene glycol) nanoparticles (PXA-PEG-NPs) using Calu-3 cells, and select one as a nasal drug delivery vector for curcumin (Cur).  Poly(γ-benzyl-L-glutamate) block-poly(ethylene glycol) nanoparticles (PBLG-PEG-NPs), poly(γ-benzyl-L-lysine) block-poly(ethyleneglycol) nanoparticles (PZLL-PEG-NPs) and poly(γ-benzyl-L-aspartate) block-poly(ethylene glycol) nanoparticles (PBLA-PEG-NPs) were prepared by emulsion-solvent evaporation method.  MTT assays were used to evaluate the cytotoxicity of PXA-PEG-NPs against Calu-3 cells.  The cellular uptake of nanoparticles was visualized by an inverted fluorescence microscope and quantified by a flow cytometer.  The results indicated that even at high concentration of 2 mg·mL⁻¹ the three nanoparticles had no cytotoxicity on Calu-3 cells.  Compared to the curcumin solution, the three curcumin-loaded PXA-PEG-NPs showed significantly higher cellular uptake efficiency on Calu-3 cells (at equal concentration of curcumin with 5 μg·mL⁻¹ Cur solution), PBLG-PEG-NPs group was the highest.  The cellular uptake increased with incubation time, and has positive correlation with nanoparticle concentration.  In brief, PXA-PEG-NPs are conducive to delivery Cur into cells, and PBLG-PEG-NPs might be provided as a good nasal drug delivery carrier.