Dynamic pH‐Responsive Release and Biological Impact of In Situ Quercetin‐Modified MIL‐101(Fe)‐NH2

A successful investigation was conducted on the in situ modification of MIL-101(Fe)-NH2 with quercetin and its controlled release under various pH conditions. MIL-101(Fe)-NH2 was synthesized using an electrochemical method at room temperature (15 volts, 30 min). The formation of the material was confirmed through comprehensive analyses, including PXRD, FTIR, and TGA. Nitrogen sorption isotherm measurements revealed that Qu@MIL-101(Fe)-NH2 exhibited a smaller surface area compared to MIL-101(Fe)-NH2, with both materials classified as mesoporous. Transmission electron microscopy (TEM) clearly depicted the materials’ octahedral microspindle morphology. The cumulative percent release (CPR) of quercetin from Qu@MIL-101(Fe)-NH2 over 72 h was determined to be 53.45 % at pH 1.2, 19.48 % at pH 4.8, and 5.87 % at pH 7.4. Notably, quercetin release in the acidic microenvironment representative of cancer cells (pH 4.8) was nearly four times higher than under physiological conditions (pH 7.4). Kinetic release studies indicated that quercetin release from Qu@MIL-101(Fe)-NH2 followed the Ritger-Peppas kinetic model, suggesting non-Fickian diffusion. The MIL-101(Fe)-NH2 nanocarriers, with in situ-loaded quercetin, demonstrated promising potential for pH-triggered drug release. Additionally, the safety of MIL-101(Fe)-NH2 in biological models and the anticancer efficacy of quercetin were evaluated in vitro using two liver cancer cell lines.