Amphiphilic\nSilane Modified Multifunctional Nanoparticles for Magnetically Targeted\nPhotodynamic Therapy

Abstract

Efficient\ntargeting is a major challenge in practical photodynamic therapy (PDT).\nThough the “enhanced permeability and retention” (EPR)\neffect is a widely used tumor targeting method, magnetic targeting\nstrategy is more promising considering the issue of high targeting\nefficiency and reducing concentration-dependent toxicity. Herein,\nmagnetic targeting and highly effective Fe₃O₄@Ce6/C6@silane NPs are reported as a class of precisely controlled\nphotosensitizers (PS) for PDT. On the basis of the amphiphilic silane\nencapsulation, PS chlorin e6 (Ce6) and Coumarin 6 (C6) as well as\nFe₃O₄ NPs were coloaded into the inside hydrophobic\nenvironment of amphiphilic silane, forming a theranostic agent for\ndual-mode imaging guided and magnetic targeting enhanced <i>in\nvivo</i> PDT agent. To solve the problem of over-irradiation,\nthe coloaded design of C6 and Ce6 molecules can afford the real time\nPDT monitoring by ratio emissions with same excitation wavelength.\nWhen Fe₃O₄@Ce6/C6@silane and Ce6/C6@silane NPs\nare compared in <i>in vitro</i> and <i>in vivo</i> experiments, the introduction of Fe₃O₄ in\nthe composite does not affect the PDT efficiency, whereas, in contrast,\nit brings MRI imaging and magnetic targeting functions. Fe₃O₄@Ce6/C6@silane injection followed with magnetic field\n(MF) and light irradiation is important in generating an effective\nPDT process, showing great potential in tumor therapy.