Ship-in-a-bottle growth of NaYF4: Yb3+/Tm3+ upconversion nanocrystals in desilicated ZSM-5 zeolite for drug release monitoring

Enabling the drug delivery systems with drug release monitoring function is of essential importance to enhance therapeutic effectiveness. Herein, we took a ship-in-a-bottle synthesis strategy to construct the upconversion nanocrystal and zeolite compounded drug delivery system with real-time monitoring function, by using desilicated ZSM-5 zeolite as drug carrier and NaYF4: Yb3+/Tm3+ nanocrystal as luminescent probe. Benefiting from the enlarged mesoporous in desilicated ZSM-5, the NaYF4: Yb3+/Tm3+ nanocrystals can be successfully loaded inside and the upconversion emission intensity of Tm3+ under 980 nm excitation was one order of magnitude enhanced after mild heat treatment. The drug release monitoring function were studied by using doxorubicin as model drug, the experimental results indicated that the upconversion emission intensity ratio of I802nm/I475nm can accurately evaluate drug release percentage. Further in vitro cytotoxicity evaluation suggested the doxorubicin-loaded [email protected]/DS/HT has excellent biocompatibility and is able to inhibit tumor cells effectively.