Curdlan (CN)-doped montmorillonite/poly(N-isopropylacrylamide-co-N,N'-methylene-bis-acrylamide) [CN/MT/P(NIPA-co-MBA)] smart nanocomposites (NCs) were developed for efficient erlotinib HCl (ERL) delivery to lung cancer cells. The placebo NCs demonstrated excellent biodegradability, pH/thermo-responsive swelling profiles and declined molar mass (M¯c) between the crosslinks with increasing temperature. The XRD, FTIR, DSC, TGA, and SEM analyses revealed the architectural chemistry of these NC scaffolds. The NCs loaded with ERL (F-1-F-3) displayed acceptable diameter (734-1120 nm) and zeta potential (+1.16 to -11.17 mV), outstanding drug entrapping capability (DEE, 78-99%) and sustained biphasic ERL elution patterns (Q8h, 53-91%). The ERL release kinetics of the optimal matrices (F-3) obeyed Higuchi model and their transport occurred through anomalous diffusion. The mucin adsorption behaviour of these matrices followed Freudlich isotherms. As compared to pure ERL, the formulation (F-3) displayed an improved anti-proliferative potential and induced apoptosis more effectively on A549 cells. Thus, the CN-doped smart NCs could be utilized as promising drug-cargoes for lung cancer therapy.
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.
Erlotinib-loaded carboxymethyl temarind gum-g-poly(N-isopropylacrylamide)-montmorillonite based semi-IPN nanocomposites were synthesized and characterized for their in vitro performances for lung cancer therapy. The placebo matrices exhibited outstanding biodegradability and pH-dependent swelling profiles. The molar mass (M¯ c) between the crosslinks of these composites was declined with temperature. The solid state characterization confirmed the semi-IPN architecture of these scaffolds. The corresponding drug-loaded formulations displayed excellent drug-trapping capacity (DEE, 86-97 %) with acceptable zeta potential (-16 to -13 mV) and diameter (967-646 nm). These formulations conferred sustained drug elution profiles (Q8h, 77-99 %) with an initial burst release. The drug release profile of the optimized formulation (F-3) was best fitted in the first order kinetic model with Fickian diffusion driven mechanism. The mucin adsorption to F-3 followed Langmuir isotherms. The results of MTT assay, AO/EB staining and confocal analyses revealed that the ERL-loaded formulation suppressed A549 cell proliferation and induced apoptosis more effectively than pristine drug.