iRGD‐paclitaxel conjugate nanoparticles for targeted paclitaxel delivery

Abstract Paclitaxel (PTX) is a chemotherapeutic agent which shows antitumor activities against a broad spectrum of cancers. Yet, the current formulation of PTX used in clinic may cause a number of adverse reactions, which significantly limit its application. To obtain better clinical use of PTX, we report, for the first time, iRGD‐PTX conjugate nanoparticles (NPs) for targeted PTX delivery. iRGD‐PTX conjugate was synthesized from thiolated iRGD and 6‐maleimidocaproic acid‐PTX through Michael addition reaction. iRGD‐PTX NPs with hydrodynamic diameter of ~110 nm were self‐assembled from iRGD‐PTX conjugate in deionized water. The as‐prepared iRGD‐PTX NPs exhibit good stability in phosphate buffered saline (PBS) buffer and fetal bovine serum containing PBS buffer. iRGD‐PTX NPs exhibit sustained drug release behaviors. The in vitro studies show that iRGD‐PTX NPs can be internalized by 4T1 cells by integrin αV‐mediated endocytosis, resulting in better in vitro antitumor activity as compared to free PTX. The in vivo studies demonstrate that iRGD‐PTX NPs exhibit enhanced tumor accumulation. The iRGD‐PTX NPs reported here represent a novel PTX nanoplatform to achieve targeted PTX delivery.