Iron doped carbon dots based nanohybrids as a tetramodal imaging agent for gene delivery promotion and photothermal-chemodynamic cancer synergistic theranostics

Nonviral gene delivery vectors for cancer therapy still confronts great challenges as their low transfection efficiency, vague tracing and poor therapeutic effects. Recently, organic-inorganic nanohybrids show complementary and synergistic effects in nano-scaled delivery system, inspiring their applications in gene delivery exploration. A liposomal carbon dots nanohybrids system (PEG-RLS/Fe@CDs) have been fabricated, which was composed of iron-doped carbon dots (Fe@CDs) derived from iron (II) phthalocyanine and amphiphilic lipopeptide assemblies (DSPE-mPEG2000/RLS). With its excellent photothermal conversion capability (eta = 63.4%), gene transfection efficiency was increased by 3.5-fold in 4T1 tumor cell and 2-fold in animal model. Introduction of Fe@CDs in the nanohybrids could also serve as a tetramodal contrast agent for fluorescence/photoacoustic/photothermal/magnetic resonance imaging, showing up to 3 orders of magnitude enhancement in photoacoustic signal, as well as 16 degrees C temperature increasement after 5 min irradiation inside tumor tissue. Furthermore, both in vitro and in vivo studies confirmed the bioactivity of PEG-RLS/Fe@CDs as nanozyme for photothermal and chemodynamic synergistic therapy, leading to a noticeable inhibited tumor growth with 80% survival for at least 50 days in a breast tumor model. These revealed the PEG-RLS/Fe@CDs is a promising candidate platform for improving gene therapy by transfection enhancement, real-time tracing and tumor synergistic destruction. (C) 2021 The Authors. Published by Elsevier Ltd.

Automated summary

Organic-inorganic nanohybrids have shown potential applications in cancer therapy by improving gene transfection efficiency and achieving real-time tracing, leading to synergistic destruction of tumors.