An Imine-Based Two-Dimensional Covalent Organic Framework for Gemcitabine Delivery

A 2D imine-linked covalent organic framework (COF) with good biocompatibility was synthesized using o-Dianisidine and 1,3,5-Triformylbenzene. The synthesized COF was characterized by using the Fourier transform infrared (FTIR), thermogravimetry analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The synthesized COF was subsequently utilized for the delivery of gemcitabine (Gem), an FDA-approved drug for the treatment of pancreatic cancer. The COF demonstrated a remarkable drug loading of 30 µg/mg and better drug release at pH 5.0. The biocompatibility of the COF was evaluated in the L929 (mouse fibroblast) cell line, while the cytotoxicity of the Gem-loaded COF (COF-Gem) was evaluated against the MIA-PaCa-2 and PANC-1 (pancreatic cancer) cell lines using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The results indicated that the COF was safe at concentrations up to 200 µg/mL, while the COF-Gem led to superior cytotoxicity as compared to native Gem, with IC50 values of 8.1 ± 1.2 µM in MIA-PaCa-2 cells and 6.0 ± 1.3 µM in PANC-1 cells after 48 h. This study offers a new perspective of utilizing COF as a promising delivery system for Gem delivery.