Preparation and characterization of mPEG‐g‐α‐zein biohybrid micelles as a nano‐carrier

Abstract

A new kind of block copolymer micelles methoxy polyethylene glycol (mPEG) grafted a-zein protein (mPEG-g-a-zein) was synthesized. The chemical composition of mPEG-g-a-zein was identified with the help of FT-IR and 1 H-NMR. The biohybrid polymer can selfassemble into spherical core-shell nanoparticles in aqueous solution. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to investigate the self-assembled morphology of mPEG-g-a-zein. Dynamic light scattering (DLS) results showed that the particle size of mPEG-g-a-zein was about 90 nm. Moreover, the nanoparticles had a very low critical micelle concentration value with only 0.02 mg/mL. Then, the anticancer drug curcumin (CUR) was encapsulated into the biohybrid polymer micelles. The in vitro drug release profile showed a zero-order release of CUR up to 12 h at 378C. Cell viability studies revealed that the mPEG-g-a-zein polymer exhibited low cytotoxicity for HepG2 cells (human hepatoma cells). Consequently, the mPEG-g-a-zein micelles can be used as a potential nano-carrier to encapsulate hydrophobic drugs and nutrients.

Micellar Drug Delivery Systems Based on Natural Biopolymers

“…Curcumin-loaded PEG–zein micelles, with an encapsulation efficiency of 95%, showed a sustained drug release and a significantly higher cell uptake than free curcumin in drug-resistant NCI/ADR-RES cancer cells in vitro. Song et al [ 165 ] investigated the same system and reached similar conclusions.…”

Biodegradable Alginate-Chitosan Hollow Nanospheres for Codelivery of Doxorubicin and Paclitaxel for the Effect of Human Lung Cancer A549 Cells

“…Currently, specific mechanisms of drug delivery have attracted much attention, such as the use of liposomes [ 8 ], nanoparticles [ 9 ], and micelles to deliver drugs to the patient [ 10 ]. However, the compatibility, stability, and toxicity of excipients must also be taken into account.…”

Limited Impact of the Protein Corona on the Cellular Uptake of PEGylated Zein Micelles by Melanoma Cancer Cells

“…This difference might be due to the different hydrophobic probes used, as well as the type of zein used as starting material. Podaralla et al used white zein, and Song et al used purified α-zein, while yellow zein was chosen in our study [19,20]. Chan et al previously demonstrated that the CMC value for diblock copolymer micelles characterized using pyrene was lower than that using Nile red (15.1 mg/mL by pyrene versus 19.5 mg/mL by Nile red) [30].…”

“…The stretching vibration of the carbonyl in the CH 2 CH 2 O groups of PEG at 840-960 cm −1 and the methyl group at 2742 cm −1 appeared in both the spectra of mPEG5K-zein and mPEG10K-zein. Furthermore, the NHS ester peak of mPEG at 1741 cm −1 disappeared after conjugation, unlike the spectra resulting from the unconjugated mixture of zein and PEG [19,20]. These demonstrated that the PEGylation of zein was successful.…”

“…To overcome this issue, the modification of zein by conjugation with poly(ethylene glycol) (PEG) has been proposed to create a steric shielding of the delivery system, thus reducing opsonization and providing a sustained release of the carried drug. Podaralla et al and Song et al previously demonstrated that PEGylation of white zein (containing a very low level of xanthophylls (less than 0.001%)) could generate stable micelles that improved the solubility and stability of the hydrophobic drug curcumin as well as enhancing its uptake by cancer cells [19,20]. So far, there have been no reports of PEGylation to yellow zein (a mixture of α, β, γ, and δ-zein, containing 8-9% of xanthophyll pigments, including lutein, zeaxanthin, and β-cryptoxanthin).…”