pH and Thermoresponsive PNIPAm-co-Polyacrylamide Hydrogel for Dual Stimuli-Responsive Controlled Drug Delivery

Abstract

The therapeutic delivery system with dual stimuli-responsiveness has attracted attention for drug delivery to target sites. In this study, we used free radical polymerization to develop a temperature and pH-responsive poly(N-isopropyl acrylamide)-co-poly(acrylamide) (PNIPAM-co-PAAm). PNIPAm-co-PAAm copolymer by reacting with N-isopropyl acrylamide (NIPAm) and acrylamide (Am) monomers. In addition, the synthesized melamine-glutaraldehyde (Mela-Glu) precursor was used as a cross-linker in the production of the melamine cross-linked PNIPAm-co-PAAm copolymer hydrogel (PNIPAm-co-PAAm-Mela HG) system. The temperature-responsive phase transition characteristics of the resulting PNIPAM-co-PAAm-Mela HG systems were determined. Furthermore, the pH-responsive drug release efficiency of curcumin was investigated under various pH and temperature circumstances. Under the combined pH and temperature stimuli (pH 5.0/45 °C), the PNIPAm-co-PAAm-Mela HG demonstrated substantial drug loading (74%), and nearly complete release of the loaded drug was accomplished in 8 h. Furthermore, the cytocompatibility of the PNIPAm-co-PAAm-Mela HG was evaluated on a human liver cancer cell line (HepG2), and the findings demonstrated that the prepared PNIPAm-co-PAAm-Mela HG is biocompatible. As a result, the PNIPAm-co-PAAm-Mela HG system might be used for both pH and temperature-stimuli-responsive drug delivery.

L-Lysine-Modified pNIPAm-co-GMA Copolymer Hydrogel for pH- and Temperature-Responsive Drug Delivery and Fluorescence Imaging Applications

“…The Lys-modified pNIPAAM-co-GMA-Lys HG sample, on the other hand, revealed higher positive zeta potential values of about +24 mV to −15.1 mV at 25 • C, and the zeta potential values were considerably increased to about + 37.3 mV to −26.2 mV in the pH range of pH 4.0 to pH 9.0 and a medium temperature of 45 • C. Moreover, the presence of negatively charged carboxylic acid groups at pH 9 resulted in a negative zeta potential value of about −26.3 mV (Figure 2b). The zeta potential results support that the functionalized Lys groups were presented in the pNIPAAM-co-GMA-Lys HG sample [33]. The swelling-deswelling and temperature-responsive phase transitions, as well as the relative turbidity of the pNIPAAm-co-GMA-Lys HG sample, were studied by using a dynamic light scattering (DLS) analysis.…”

Stimuli‐Responsive and Multifunctional Nanogels in Drug Delivery

“…The cytocompatibility test of the loaded drug on a human liver cancer cell line (HepG2) assessed the hydrogel system as biocompatible. The overall findings promise an equipped nanocarrier for target specific delivery of drugs in a controlled manner [146] …”

“…The overall findings promise an equipped nanocarrier for target specific delivery of drugs in a controlled manner. [146] Fe 3 O 4 À SiO 2 -poly (NVCL-co-MAA) nanocomposite, another pH and temperature-sensitive drug carrier was devised by grafting the copolymer poly(N-vinyl caprolactam-co-methacrylic acid) (poly(NVCL-co-MAA)) onto the vinyl functionalized, SiO 2 coated Fe 3 O 4 nanoparticles through free radical polymerization. The synthesis aimed at releasing the anticancer drug Doxorubicin (DOX) in light of previous findings regarding the drug's release profile, which depended on pH and temperature.…”

Fabrication and testing of bioinspired microstructured alumina composites with sacrificial interpenetrating polymer bonds

“…Among the numerous stimuli-responsive hydrogels, the thermoresponsive PNIPAM has been heavily studied as drug delivery systems and in other biomedical applications [20]. Above 37 • C in aqueous medium, the PNIPAM undergoes an abrupt phase transition change from an extended hydrophilic state to a collapsed hydrophobic state, which works well in releasing any loaded drugs [20,27]. A dual pH and thermoresponsive hydrogel can be fabricated using PNIPAM with pH-sensitive PAM, another well-known hydrogel that swells at alkaline pH and collapses at acidic pH [28].…”