Carboxymethyl fenugreek galactomannan-g-poly(N-isopropylacrylamide-co-N,N′-methylene-bis-acrylamide)-clay based pH/temperature-responsive nanocomposites as drug-carriers

The current study dealt with the synthesis and characterization of carboxymethyl fenugreek galactomannang-g-poly(N-isopropylacrylamide-co-N,N′-methylene-bis-acrylamide)-bentonite [CFG-g-P(NIPA-co-MBA)-BEN] based nanocomposites (NCs) as erlotinib (ERL)-delivery devices for lung cancer cells to suppress excessive cell proliferation. The blank NCs exhibited outstanding biodegradability and pH/temperature-dependent swelling profiles, which were significantly influenced by their BEN contents (0–20%). The molar mass ( M ¯ c) between the crosslinks of these NCs was declined with temperature. The composite architecture of these scaffolds was confirmed by XRD, FTIR, TGA, DSC and SEM analyses. The corresponding ERL-loaded matrices (F-1-F-3) portrayed outstanding drug encapsulation efficiency (DEE, 93–100%) with zeta potential between −8 and −16 mV and diameter between 615 and 1258 nm. These formulations demonstrated sustained ERL elution profiles (Q8h, 62–98%) with an initial burst release of drug. The drug dissolution pattern of the optimized matrices (F-3) obeyed first-order kinetic model and was driven by Fickian diffusion. The mucin adsorption behavior of F-3 was best fitted to Freudlich isotherms. The ERL-loaded formulation suppressed A549 cell proliferation and promoted apoptosis to a greater extent than the pristine drug, as detected by cellular uptake analysis, MTT cytotoxicity test and AO/EB staining assay.