Boosting the\nSustained Release Performance of Metronidazole\nand Ornidazole with MIL-53(Fe) Derived Spherical Porous Carbon

Metal–organic framework (MOF) derived spherical\nporous carbon\n(SPC) has potential application value in the field of adsorption and\nsustained release of nitroimidazole drugs. This work used MIL-53(Fe)\nas a precursor and prepared spherical 3-aminophenol-formaldehyde resin\ncontaining MIL-53(Fe) crystals using the advanced Stöber method,\nfollowed by the successful preparation of MIL-53(Fe) derived SPC (MSPC)\nwith a structure containing both micropores and mesopores through\nhigh-temperature carbonization. The effects of the doping amount of\nMIL-53(Fe) on the sphericity and particle size of MSPC were investigated.\nThe drug uptake capacity and sustained release performances of MSPC\nfor metronidazole (MNZ) and ornidazole (ONZ) were assessed through\nbatch tests, along with an investigation into the impact of varying\npH levels on the sustained release performances. The experimental\nfindings revealed that the drug loading of MNZ and ONZ onto MSPC achieved\n111 and 120 mg/g, respectively, with a sustained release time of up\nto 24 h. The drug loading process adhered to the Langmuir isotherm\nadsorption model and conformed to the pseudo-second-order kinetics\nmodel, whereas the sustained release mechanism was consistent with\nthe Korsmeyer–Peppas model. Furthermore, cytotoxicity and cyclic\ndrug loading experiments indicated that MSPC exhibited good biocompatibility\nand stability. Therefore, this study provides new ideas for the development\nof SPC drug carriers.