Multifunctional aptamer-conjugated magnetite graphene oxide/chlorin e6 nanocomposite for combined chemo-phototherapy

Herein, aptamer-functionalized magnetite Fe3O4@graphene oxide/photosensitizer nanocomposite was designed and prepared for chemo-photothermal/photodynamic therapies. Chlorin e6 (Ce6, as a photosensitizer) is used to conjugate with magnetite graphene oxide (Fe3O4@GO). The structure of Fe3O4@GO@Ce6 nanocomposite was characterized by using FTIR, UV, TGA, XRD, VSM and TEM methods. An antineoplastic drug, paclitaxel (Pac), was loaded onto Fe3O4@GO@Ce6 nanocomposite, forming a Fe3O4@GO@Ce6@Pac nanocomplex. The Fe3O4@GO@Ce6 nanocomposite was functionalized with aptamer (Apt) for selective killing of MCF-7 tumor cells. Fe3O4@GO@Ce6@Pac nanocomposite offers a notably enhanced tumor cell photodynamic destruction impact compared to free Ce6. It is displayed that the photothermal impact of magnetite Fe3O4@GO@Ce6 nanocomposite can be used to promote the Ce6 release when irradiated to a near-infrared laser at a low power density, further improving the photodynamic therapy efficiency on tumor cells. It is observed that the Fe3O4@GO@Ce6 nanocomposite possessed good colloidal/photo stability, biocompatibility, and high loading capacity for Pac. Furthermore, compared to the free Ce6, the Fe3O4@GO@Ce6@Apt-Pac nanocomposite display significantly enhanced photodynamic efficacy. Due to its intrinsic optical features, ultrahigh specific surface area, targeting ability, and unique physical interactions with aromatic active agents, Fe3O4@GO@Ce6@Apt-Pac is a promising new nanomaterial for medical and biological applications.

Automated summary

In this study, an aptamer-functionalized magnetite Fe3O4@graphene oxide/photosensitizer nanocomposite was designed and prepared for chemo-photothermal/photodynamic therapies. The nanocomposite showed enhanced tumor cell photodynamic destruction and improved therapy efficiency through the photothermal effect. It possessed good stability, biocompatibility, and high loading capacity for the antineoplastic drug paclitaxel. The nanocomposite, with its intrinsic optical features, ultrahigh specific surface area, targeting ability, and unique physical interactions, is promising for medical and biological applications.