Stabilizing nitric oxide: MnFe2O4@Cap-SNO nanoparticles and chitosan hydrogels for controlled therapeutic delivery.

Nitric oxide (NO) is a vital bioactive molecule, but its rapid degradation limits therapeutic applications. To enhance stability and controlled release, two novel systems were synthesized: MnFe2O4@Cap-SNO nanoparticles and Cs@Cap-SNO hydrogel. MnFe2O4@Cap-SNO, incorporating captopril (Cap) as an NO donor, demonstrated prolonged NO release for up to 16h upon light exposure, following zero-order kinetics, ensuring sustained delivery. Cs@Cap-SNO, a chitosan-based hydrogel integrating nitrosated captopril (Cap-SNO), exhibited faster NO release governed by Korsmeyer-Peppas kinetics. UV-Vis spectrophotometry confirmed successful nitrosation with distinct absorption bands at 335nm and 545nm. MnFe2O4@Cap-SNO displayed superior stability, outperforming Cs@Cap-SNO and free Cap-SNO in NO preservation. These findings suggest MnFe2O4@Cap-SNO as an effective NO-stabilizing carrier for biomedical applications, particularly intargeted drug delivery. Future studies will focus on in vitro and in vivo validation to assess therapeutic efficacy.