Zeolitic Imidazole Framework/Silica Nanocomposite for Targeted Cancer Therapeutics: Comparative Study of Chemo-Drug Cisplatin (CPt) and Green Platinum (GPt) Efficacy

A chemo-drug such as cisplatin is effective for cancer treatment but remains non-specific, is susceptible to drug resistance, and induces several side effects on organ systems. Zeolitic imidazolate framework-8, a type of MOF, has gained attention, including as a drug delivery method for targeted cancer therapeutics. In this study, ZIF-8/Silica nanocomposite was synthesized using a one-pot hydrothermal technique using the Stober technique. We studied the effect of phyto-synthesized GPt and chemo-drug cisplatin CPt on ZIF-8/Silica for targeted efficacy of cancer therapy. The texture, morphology, and chemical environment of Pt on ZIF-8/Silica were analyzed using different characterization techniques such as XRD, FT-IR, BET, diffuse reflectance spectroscopy, SEM-EDX, TEM, zeta potential, and TGA analysis. The isothermal behavior of CPt and GPt adsorption was investigated using isotherm models like Langmuir, Freundlich, and Temkin isotherm. The adsorption kinetics indicating the adsorption efficiency of GPt and CPt are influenced by the concentration of Pt complex and the adsorption sites of ZIF-8/Silica. A high entrapment efficiency and loading capacity of GPt (86% and 4.3%) and CPt (91% and 4.5%) were evident on ZIF-8/Silica. The nanocomposite showed a pH-sensitive Pt release using a dialysis membrane technique. For instance, a high release of GPt (93%) was observed under pH = 6.6 in 72 h, while the release reduced to 50% at pH 7.4 in 72 h. The anti-cancer activity of nanoformulations was studied in vitro using MCF7 (breast cancer cells) and HFF-1 (human foreskin fibroblast) cells. The findings demonstrated that GPt is as effective as CPt; the EC50 value for MCF7 cells treated with ZIF-8/Silica/Cp/PEG was 94.86 µg/mL, whereas for ZIF-8/Silica/GPt/PEG it was 60.19 µg/mL.