Porous nanoparticles with engineered shells release their drug cargo in cancer cells

• Published in: International journal of pharmaceutics 2021-12, Vol.610, p.121230-121230, Article 121230
• Main Authors: Qiu, Jingwen, Li, Xue, Rezaei, Mahsa, Patriarche, Gilles, Casas-Solvas, Juan M., Moreira-Alvarez, Borja, Costa Fernandez, Jose Manuel, Encinar, Jorge R., Savina, Farah, Picton, Luc, Vargas-Berenguel, Antonio, Gref, Ruxandra
• Format: Article
• Language: English
• Subjects: Doxorubicin; Metal-Organic Frameworks; Nanoparticles; Neoplasms; Pharmaceutical Preparations; Poly(ethylene glycol) (PEG); Porosity; Surface modification
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2021.121230

[Display omitted] Highly porous nanoscale metal–organic frameworks (nanoMOFs) attract growing interest as drug nanocarriers. However, engineering “stealth” nanoMOFs with poly(ethylene glycol) (PEG) coatings remains a main challenge. Here we address the goal of coating nanoMOFs with biodegradable shells using novel cyclodextrin (CD)-based oligomers with a bulky structure to avoid their penetration inside the open nanoMOF porosity. The PEG chains were grafted by click chemistry onto the CDs which were further crosslinked by citric acid. Advantageously, the oligomers’ free citrate units allowed their spontaneous anchoring onto the nanoMOFs by complexation with the iron sites in the top layers. Up to 31 wt% oligomers could be firmly attached by simple incubation with the nanoMOFs in an aqueous medium. Moreover, the anticancer drug doxorubicin (DOX) was successfully entrapped in the core–shell nanoMOFs with loadings up to 41 wt%. High resolution STEM (HR-STEM) showed that the organized crystalline structures were preserved. Remarkably, at the highest loadings, DOX was poorly released out of the nanoMOFs at pH 7.4 (