Actively targeted gold-polydopamine (PDA@Au) nanocomplex for sequential drug release and combined synergistic chemo-photothermal therapeutic effects

Multifunctional nanoparticles for treatment in cancer are getting more and more attention recently. In this study, we employed a novel polydopamine (PDA) framework-based gold nanoparticles as a carrier of an antimetabolite drug, 5-Fluorouracil (5-FU). Folic acid (FA) was embellished onto the surface of nanoparticle imparting the nanosystem with remarkable tumor-targeting abilities through its precise binding with FA receptor that is notably overexpressed in breast cancer cells. PDA served as a photothermal treatment (PTT) agent and a gate-keeper to regulate drug release since it is highly pH-sensitive and might lengthen the residency period while simultaneously enhancing water solubility and biological compatibility of nanomaterials. Gold nanoparticles (Au NPs) end up serving as both a drug delivery platform and a source of substantial photothermal effects, culmi-nating in synergistically coupled chemo-photothermal therapy. The PDA@Au@FA nanocomplex, loaded with 5 -FU, is biocompatible, features strong NIR absorption and photothermal conversion, and can control drug release in pH/NIR dual response environment. The cell viability in PDA@Au@5-FU-FA group with NIR irradiation in 48 h was only 20.1 +/- 2.6%. In addition, apoptosis staining experiments revealed greater cellular uptake of PDA@Au@5-FU-FA by MCF-7 cells. Therefore, PDA@Au@5-FU-FA nanocomplex that we postulated herein may be a potential contender for effective curative treatment for breast cancer.

Automated summary

This study highlights the use of multifunctional nanoparticles for targeted cancer treatment. By employing polydopamine-based gold nanoparticles as drug carriers, the researchers were able to achieve tumor-targeting abilities. The nanoparticles were modified with folic acid, allowing for precise binding with breast cancer cells. This nanosystem exhibited biocompatibility, strong NIR absorption, and controlled drug release in response to pH and NIR stimulation.