Characterization of Kaolinite Single Methoxy Nano-Sheets as Potential Carriers of Oxaliplatin Drug of Enhanced Loading, Release, and Cytotoxicity Properties During the Treatment of Colorectal Cancer

Kaolinite mineral was exfoliated into single nano-sheets (EXFK) and functionalized by methanol forming novel methoxy kaolinite nanosheet (MX/EXFK) as effective carrier of oxaliplatin drug (OXP). The functionalization of EXFK notably enhanced the loading properties to 433 mg/g (MX/EXFK) instead of 304.9 mg/g (EXFK). The loading reactions by EXFK and MX/EXFK follow the Pseudo-first order kinetics (R 2 > 0.94) and classic Langmuir isotherm (R 2 = 0.99). MX/EXFK shows enhanced active sites density (109.9 mg/g) as compared to 66.3 mg/g (EXFK) and each site can be loaded with 4 molecules by multi-molecular mechanism. The encapsulation energy (< 40 kJ/mol) and Gaussian energy (< 8 kJ/mol) validates the dominant physical encapsulation mechanism of OXP. The release behavior of OXP from MX/EXFK demonstrates continuous and controlled profiles up to 100 h (pH) and 180 h (phosphate buffer). The release processes exhibit non-Fickian transport properties according to the kinetic studies and diffusion exponent values (0.52–0.61). The synthetic structures exhibit considerable cytotoxicity effect on HCT-116 cancer cell lines (EXFK (71.4% cell viability); MX/EXFK (12.08% cell viability). Moreover, these carriers induce the cytotoxic effects of OXP significantly (OXP/EXFK (2.04% cell viability); OXP/MX/EXFK (0.95% cell viability).