Exploration of Fe III -Phenol Complexes forPhotothermal Therapy and Photoacoustic Imaging

Photothermal therapy (PTT) has received extensive attention due to its excellent antitumor effect, specific selectivity, and minimal invasiveness. FeIII-phenol complexes with good biocompatibility and biosafety have widespread applications in PTT. However, the comparison of different FeIII-phenol complexes for photoacoustic imaging (PAI) and PTT has been rarely reported. Herein, we prepared a series of FeIII-phenol complexes using phenols with different structures via a simple one-step method. Then, we systematically investigated their ultraviolet–visible (UV–vis) absorbance, photothermal performance, and PAI capability. Phenols, including ortho diphenol or triphenol, were important components of FeIII-phenol complexes with strong capacity for UV–vis absorbance, photothermal performance, and PAI. The representative FeIII-pyrocatechol (PC) and FeIII-tannic acid (TA) complexes exhibited excellent photothermal performance and could induce MCF-7 cell death with laser irradiation. Moreover, FeIII-PC and FeIII-...