Integration of temperature-sensitive hydrogels loaded with realgar and magnetic particles for lung cancer diagnosis and treatment

Introduction : Lung cancer has a high incidence rate and a poor prognosis with traditional treatments like surgery and radiotherapy, necessitating the active exploration of new treatment methods. Realgar (AS4S4), a traditional Chinese medicine, has chemotherapeutic efficacy. However, its low solubility, complex dosage form, and single therapeutic efficacy limit its further application in modern medicine. To monitor tumors and combine magnetic induction thermotherapy, magnetic iron oxide (Fe3O4) particles were introduced, and a local injection therapy system was developed by combining the two with a temperature-sensitive hydrogel. Methods : AS4S4 was chemically synthesized using hydrochloric acid to disrupt the bonding between AS and NH2 to obtain andrography nanoclusters, which improved the solubility and reduced the toxic side reactions. Furthermore, Fe3O4 nanoparticles were introduced, and the two performance nanomaterials were combined using a smart temperature-sensitive hydrogel to construct a locally injected nanodiagnostic therapy with fluorescence and magnetic resonance imaging dual-modal imaging-guided chemotherapy and magneto-induced thermotherapy combined unit (AS4S4/Fe3O4@Gel). Results : Characterization results showed that the hydrogel exhibited satisfactory temperature sensitivity, 85% controlled drug release at 42 ^o C, and good biocompatibility. The results of cellular experiments showed that AS4S4/Fe3O4@Gel induced apoptosis and iron death in lung cancer cells, while the combination with magnetic induction hyperthermia (ACMF) significantly inhibited tumor cell proliferation. In a mouse model of transplanted tumors in Holland Lewis cells, AS4S4/Fe3O4@Gel showed good fluorescence properties and magneto-thermal effects. The combined ACMF group exerted better antitumor effects than the negative control group. Conclusion : The AS4S4/Fe3O4@Gel prepared in this study can exert synergistic antitumor activity in combination with ACMF under bimodal imaging guidance, and it is a potential means of clinical treatment for lung cancer.