Novel nanocomposite materials of silver-exchanged clinoptilolite with pre-concentration of Ag(NH3)2+ in water possess enhanced anticancer action

Insight into the Loading Properties of Na+ Green-Functionalized Clinoptilolite as a Potential Carrier for the 5-Fluorouracil Drug, its Release Kinetics, and Cytotoxicity

Herein, natural zeolite (clinoptilolite) was functionalized by Na⁺ ions (G.Na⁺/Clino) utilizing a green tea extract prepared by a green production method as a potential carrier for the 5-fluorouracil (5-Fu) drug with enhanced physicochemical behaviors. The G.Na⁺/Clino-modified product showed enhanced surface area (312 m²/g) and ion-exchange capacity (387 mequiv/100 g). The loading studies reflect high and controlled loading properties of G.Na⁺/Clino with an actual loading capacity of 291 and 462 mg/g, respectively. The loading reactions of 5-Fu into G.Na⁺/Clino were of pseudo-second-order kinetics and exhibited Langmuir isotherm properties. This suggested a monolayer and homogeneous loading process by chemical complexation and ion-exchange mechanisms with a Gaussian energy value of 10.47 kJ/mol. Additionally, these reactions were of endothermic and spontaneous nature based on the determined thermodynamic parameters. The release studies demonstrated the 5-Fu release profile for about 150 h at pH 1.2 and for 80 h at pH 7.4. The release reactions had non-Fickian transport properties and were controlled by both erosion and diffusion mechanisms, considering the release kinetic findings and the values of the diffusion exponent (0.42 at pH 1.2 and 0.37 at pH 7.4). The composite showed remarkable biocompatibility based on the measured cell viability and a cytotoxic effect on normal colorectal cells (CCD-18Co). Additionally, the application of G.Na⁺/Clino as an inorganic carrier for the 5-Fu drug prompted the cytotoxic effect of the drug on colon cancer cell treatment (HCT-116).

Insight into the Technical Qualification of the Sonocogreen CaO/Clinoptilolite Nanocomposite (CaO(NP)/Clino) as an Advanced Delivery System for 5-Fluorouracil: Equilibrium and Cytotoxicity

Clinoptilolite as a natural zeolite was integrated with green CaO nanoparticles forming the green nanocomposite CaO_(NP)/Clino. The CaO_(NP)/Clino composite was assessed as a potential carrier for 5-fluorouracil (5-FL) drug. The CaO_(NP)/Clino carrier achieved an enhanced 5-FL loading capacity of 305.3 mg/g as compared to 163 mg/g for pure clinoptilolite. The kinetics of the 5-FL loading follow the properties of the pseudo-first-order model, while the equilibrium results are related to the Langmuir isotherm. Therefore, the 5-FL loading processes occurred in the monolayer formed by homogeneous active loading receptors on the surface of the CaO_(NP)/Clino carrier. The Gaussian energy of the 5-FL loading reaction (9.2 KJ/mol) reflected the dominant effect for the chemical mechanisms, especially the zeolitic ion-exchange mechanisms. Additionally, the thermodynamic parameters suggested endothermic, feasible, and spontaneous properties for the occurred 5-FL loading reactions. The release profile of 5-FL from CaO_(NP)/Clino has continuous and long properties (150 h) at pH 1.2 (gastric fluid) and pH 7.4 (intestinal fluid). The kinetic studies of the release reactions show considerable agreement with Higuchi, Hixson-Crowell, and Korsmeyer-Peppas models. Such high fitting results and the diffusion exponent values (0.49 at pH 1.2 and 0.48 at pH 7.4) reflected the release properties of the Fickian transport behavior involving complex erosion and diffusion mechanisms. The cytotoxicity study of CaO_(NP)/Clino on colorectal normal cells (CCD-18Co) declare the safe and biocompatible effect as a carrier for the 5-FL drug. Additionally, CaO_(NP)/Clino as a carrier causes considerable enhancement for the cytotoxic effect of the loaded 5-FL drug on colon cancer cells (HCT-116).