Rapid synthesis of CuTA/Cur@ZIF-8 multifunctional drug delivery system towards cancer treatment

Abstract

The multifaceted progression of cancer requires the implementation of nano-drug delivery systems (DDS) with enhanced functionalities to strengthen therapeutic effectiveness. Accordingly, we designed CuTA/Cur@ZIF-8 hybrid nanoparticles to enable localized drug release at the tumor site and effectively scavenge excessive free radicals in this region. To achieve these objectives, the pH-sensitive structure of zeolitic imidazolate framework-8 (ZIF-8) was employed as the drug carrier. Meanwhile, the copper-tannic acid (CuTA) complex was used as a surface coating for the hybrid nanoparticles, serving as a free radical scavenger and a biocompatibility enhancer. Hydrophobic curcumin (Cur) was also selected as a model anticancer drug for this multifunctional DDS. Notably, the synthesis of CuTA/Cur@ZIF-8 was completed within approximately 20 min under mild conditions (room temperature, magnetic stirring, and atmospheric pressure). Analytical results demonstrated that CuTA/Cur@ZIF-8 exhibited an exceptionally high Cur encapsulation efficiency of approximately 95.61 % while inheriting the advantageous properties of its components. The pH-responsive Cur release behavior of CuTA/Cur@ZIF-8 was also investigated, revealing that approximately 63.17 % of Cur was released at pH 5.5, which was 6.22 times higher than that at pH 7.4. Furthermore, a concentration of CuTA/Cur@ZIF-8 at 50 μg/mL was shown to be optimal for activating its biological functionalities, including free radical scavenging, cancer cell eradication, and non-toxicity to normal cells.