Characterization of cellulose-functionalized phillipsite biocomposite as an enhanced carrier of oxaliplatin drug during the treatment of colorectal cancer: loading, release, and cytotoxicity

Natural phillipsite (N.Ph) was hybridized with cellulose fibers to produce a safe biocomposite (CF/N.Ph) as an enhanced delivery structure of traditional oxaliplatin (OXPN) chemotherapy during the treatment stages of colorectal cancer cells. The requirements of CF/N.Ph as a carrier for OXPN were followed based on the loading, release, and cytotoxicity compared to N.Ph. CF/N.Ph composite exhibits a notably higher OXPN encapsulation capacity (311.03 mg g^-1) than the N.Ph phase (79.6 mg g^-1). The OXPN encapsulation processes into CF/N.Ph display the isotherm behavior of the Freundlich model (<i>R</i>² = 0.99) and the kinetic assumptions of pseudo-first order kinetic (<i>R</i>² > 0.95). The steric studies reflect a strong increment in the quantities of the free sites after the cellulose hybridization steps (Nm = 100.01 mg g^-1) compared to pure N.Ph (Nm = 27.94 mg g^-1). Additionally, the capacity of each site was enhanced to be loaded by 4 OXPN molecules (<i>n</i> = 3.11) compared to 3 by N.Ph (<i>n</i> = 2.85) in a vertical orientation. The OXPN encapsulation energy into CF/N.Ph (<40 kJ mol^-1) reflects physical encapsulation reactions involving electrostatic attraction, van der Waals forces, and hydrogen bonding. The OXPN release profiles of CF/N.Ph exhibit slow and controlled properties for about 150 h either at pH 5.5 or at pH 7.4. The release kinetics and diffusion exponent (>0.45) signify non-Fickian transport and a complex erosion/diffusion release mechanism. The free CF/N.Ph particles display a considerable cytotoxic effect on HCT-116 cancer cells (46.91% cell viability), and its OXPN-loaded product shows a strong cytotoxic effect (3.14% cell viability).