Fig. 2

UV–vis absorption and fluorescence spectral analysis of \(\hbox {CeO}_2\) and \(\hbox {CeO}_2\) NPs-DOX with different morphologies. (a) UV–vis of bare \(\hbox {CeO}_2\), (b) UV–vis and (c) fluorescence emission spectra of supernatants after incubation with DOX for different \(\hbox {CeO}_2\) morphologies. The absorbance corresponds to unbound DOX, decreased peak intensity indicates greater drug uptake by the nanoparticles. (d) Visual confirmation of DOX loading under UV illumination. DOX emitted fluorescence, confirming the successful loading of DOX onto the \(\hbox {CeO}_2\).