Real-Time Drug Delivery System Tracked Through an Optical Microfiber: Supporting Interface of Metal-Organic-Framework

Effective chemotherapy treatment for cancer patients remains an urgent issue due to the difficulty in precisely delivering drugs to the tumor site. Based on the pH-responsive degradation characteristics of the zeolitic imidazolate framework (ZIF-8), the optical fiber drug delivery system is proposed to achieve efficient drug loading and release. ZIF-8 nanomaterial prepared by in-situ synthesis technology is not only the protective shell of the drug (doxorubicin hydrochloride, DOX) but also as the analyte collector on the optical fiber, which monitors the process of nano-scale drug loading and releases in real-time because of the refractive index (RI) change caused by the interaction of light and DOX@ZIF-8 films. The experimental results show that the successful loading and release of the drug are respectively calibrated by wavelength red-shift (53 nm) and blue-shift (43.42 nm) with a loading rate of 11.6%. The drug release process also achieved a faster response time. These observations indicate that the metal-organic framework (MOF) material coated on optical fiber can retain the robust framework structure and demonstrate that the fiber-based drug delivery platform has the advantages of fast response, high sensitivity, and good photophysical stability, which provides new insights for combination cancer therapy and precise treatment.