Development of doxorubicin-loaded chitosan–heparin nanoparticles with selective anticancer efficacy against gastric cancer cells in vitro through regulation of intrinsic apoptosis pathway

Supplementation of Polymeric Reservoirs with Redox-Responsive Metallic Nanoparticles as a New Concept for the Smart Delivery of Insulin in Diabetes

“…In the drug delivery field, this terminological umbrella has encompassed materials capable of releasing their pharmaceutical loads only upon experiencing a specific physical or chemical stimulus from the environment. Common examples include materials comprising disulfide bonds cleaving in response to the reductive intracellular thiol, glutathione [ 1 , 2 ], which cancer cells contain in greater abundance than normal ones [ 3 ]; polythiols swelling due to a sulfoxide → sulfone transition promoted under oxidative stress mediated by reactive oxygen radical scavengers and releasing entrapped drugs accordingly [ 4 , 5 ]; particles binding a drug through a hydrazone bond, which is stable under neutral conditions but breaks at an acidic pH [ 6 , 7 ]; thermosensitive hydrogels undergoing sol–gel transition at a critical temperature that is the function of the monomer ratio, molecular weight and its distribution, terminal functional groups and copolymer concentration [ 8 ]; endosomal escape of the drug load achieved by the selective dissolution of calcium phosphate nanoparticles as drug carriers inside acidic lysosomes [ 9 , 10 , 11 ]; alterations in the compactness and drug binding strength of chitosan particles as a function of pH due to the protonation/deprotonation of constitutive amine groups [ 12 , 13 ]; the shape memory effect, where the material revives its prior structure after severe deformation [ 14 , 15 ]; and others.…”