An imine based COF as a smart carrier for targeted drug delivery: From synthesis to computational studies

Covalent Organic Frameworks (COFs) are a remarkable class of porous solids and they are defined as organic polymeric materials having a large surface area and chemical stability. COFs have been widely used for nano-technology applications, but there is limited number of reports regarding the COFs application as drug delivery system. In the study, a two-dimensional imine-linked DT-COF (2D-COF) was synthesized using building blocks of 3,3'-dimethoxybenzidine (DMB) and 1,3,5-triformylbenzene (TFB). The newly synthesized DT-COF (2D-COF) was tested as a drug carrier system. Firstly, the synthesized COF was characterized using the FT-IR, SEM, TGA, XRD, and elemental analysis. Then the COF was used for targeted delivery of carboplatin, which is an antineoplastic drug for the treatment of cancer. Drug loading capacity of COF was recorded significantly high as 31.32%. Cumulative drug releasing from the CP-COF was studied at pH 7.4 and 5.0 and the release kinetic mechanism was explained by zero-order, first-order and Higuchi kinetic models. The carboplatin release from CP-DT-COF was observed minimum at physiological pH of normal cells and the fast drug release started at pH = 5.0 of cancer cells. In order to get a further insight of carboplatin loaded DT-COF (CP-DT-COF), an ab initio/DFT study was carried out on the model system in B3LYP/6-31G* level. The theoretical calculation results proved that H bonds and C-H-pi interactions occurred between the carboplatin and DT-COF. According to the experimental and theoretical calculation results, it was concluded that the newly synthesized DT-COF could be used as a drug carrier system.