Microwave Triggered Release of Doxorubicin from Metal-organic Frameworks

Abstract

Metal-Organic Frameworks (MOFs) are ideal candidates for a variety of applications based on their remarkable properties such as high surface area and porosity. A substantial number of studies have been conducted to examine the synthesis techniques of MOFs as well as their implementation in drug delivery, biosensing, adsorption, separation, etc. An extensive overview of the recent work performed to explore the structure, properties, and applications of MOFs was reviewed, in order to establish a strong foundation for this research. In recent times, stimuli responsive MOFs have been fabricated and investigated for their utilization in targeted drug delivery applications with the help of Ultrasound, Light and heat. We proposed the utilization of Microwaves (MW) for stimulus responsive in-vitro release of Doxorubicin (DOX) from MOFs named Fe-BTC and MIL-53(Al) for the purpose of drug delivery in cancer therapy. DOX was encapsulated into Fe-BTC and MIL-53(Al) overnight and the drug loading capacity was measured to be as high as 67% for Fe-BTC and 20-40% for MIL-53(Al). Several characterization tests were performed to confirm and explain the drug loading and releases mechanism from both MOF’s samples, including XRD, FTIR, TGA, BET, FE-SEM and EDX. Fe-BTC exhibited drug release efficiency of 54% after 50 minutes as a result of Microwave at 7.4 pH whereas 11% was achieved without Microwave. Similar observation was obtained at pH 5.3, however the release efficiencies in both cases were higher with Microwave (40%) compared to without (6%). MIL-53(Al) was observed to be more pH sensitive as it showed higher release (66%) after 38 minutes in pH 5.3as compared to 55% after 50 minutes at pH 7.4 with the application of Microwave irradiation. The experimental results revealed that both MOFs were highly heat responsive. Moreover, results of MTT assay revealed that the cells remained viable at different concentrations of the MOFs after two days of incubation verifying their biocompatibility which demonstrates that MOFs could be good candidates for tumour targeting. Additionally, the cells remained viable at different exposure lengths confirming that Microwave is a safe modality to use for triggering release of a drug from MOFs.