Stimuli‐Responsive Materials Used as Medical Devices in Loading and Releasing of Drugs

Comonomer effect: Switching the lower critical solution temperature to upper critical solution temperature in thermo‐pH sensitive binary graft copolymers

“…The main objective of surface modification is exploring more potential applications for hydrophobic materials that generally have limitations due to their lack of biocompatibility or their prone to bacterial adhesion . There are several ways to induce a surface modification; however, grafting‐radiation method is one of the most interesting and useful technique to modify a wide variety of polymers without need to use chemical initiator . The ionizing radiation energy helps to create free radicals over the entire surface, which then react with vinyl monomers forming polymer chains …”

“…Stimuli‐sensitive polymers are a class of polymers that can undergo a reversible phase transition as response to changes in their environmental conditions such as magnetic field, ionic force, light, pH, and temperature . Among all stimuli‐sensitive polymers, thermo‐responsive and pH‐sensitive materials are the most studied by their promising applications as drug carriers.…”

“…Among all stimuli‐sensitive polymers, thermo‐responsive and pH‐sensitive materials are the most studied by their promising applications as drug carriers. Thermo‐sensitive polymers are intensively studied by their phase transitions in aqueous medium; as for example, poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA) which has a LCST of 38 °C approximately; poly(N‐vinylcaprolactam) (PNVCL) and poly(N‐isopropylacrylamide) (PNIPAAm) that exhibit a similar critical temperature close to 32–34 °C, it means that they are hydrated below this temperature, but above 32 °C they are dehydrated (in aqueous medium) . On the other side, polymers that exhibit an UCST are those with hydrophobic behavior below certain critical temperature but above this, they show a better affinity to water .…”