Sodium alginate coated metal organic framework for near infrared triggered release

Researchers are actively exploring novel approaches to administer chemotherapy medications more effectively with fewer adverse side effects. Therein, the use of polymer-coated metal-organic frameworks, MOFs, is a viable option for pH- and light-responsive nanocarriers in controlled drug delivery due to their distinctive physicochemical characteristics. The polymer-coated MOF maximizes synergistic antitumor activity by combining the benefits of physiological stability, tumor microenvironment pH responsiveness, and high drug encapsulation efficiency while simultaneously delivering drugs to cancer cells. In this study, commercially synthesized NH2−MIL-125(Ti), a titanium-based MOF with a BET surface area of 847 m2/g, was coated with the sodium alginate (SA) polymer after encapsulating doxorubicin (DOX). The drug-release efficiency of the NH2−MIL-125(Ti)@DOX-SA nanocomposite at pH 5.3 and 7.4 was investigated under Near-infrared Light (NIR) irradiation as an external stimulus. Remarkably, the NH2−MIL-125(Ti) nanocarrier achieved a high loading efficiency of DOX 94%, with DOX release increasing from 7.7% (control) to 51% (NIR-light) at pH 5.3, whereas at pH 7.4, 9% was released in the control and only 39% under NIR-light. The Reactive Oxygen Species (ROS) test confirmed that the NH2−MIL-125(Ti) produces a measurable amount of •OH radicals under the NIR radiation, which is confirmed by the visible blue color of the solution mixture and a high absorbance peak at 650 nm. Various characterization tests were also conducted to analyze the material, including FTIR, in which the stretching vibration of the CO bond of DOX at 1650 cm−1 indicated successful loading of DOX onto the nanocarrier. XRD results showed that NH2−MIL-125(Ti) has a stable and crystalline structure. TGA showed the nanocarrier was stable up to 520 °C. Furthermore, in vitro cytotoxicity studies using MCF-7 breast cancer cells revealed that NIR-triggered NH2−MIL-125(Ti)@DOX-SA treatment significantly reduced cell viability (63%) compared to untreated (control cells) or unirradiated groups (89%), confirming the enhanced therapeutic effect of the dual-responsive system. Overall, the use of polymer-coated MOFs, especially NH2−MIL-125(Ti), is a promising approach for advancing controlled and effective drug delivery in cancer treatment, offering potential benefits in both efficiency and reduced adverse effects.