Targeted photodynamic therapy technique of Janus nanoparticles on breast cancer

Spherical gold/polyacrylic acid (Au/PAA) polymer–inorganic Janus nanoparticles (JNPs) with simultaneous therapeutic and targeting functions were fabricated. The obtained Au/PAA JNPs were further selectively functionalized with folic acid (FA) and thiol PEG amine (SH-PEG-NH₂) on Au sides to provide superior biocompatibility and active targeting, while the other PAA sides were loaded with 5-aminolevulinic acid (5-ALA) to serve as a photosensitizer (PS) for photodynamic therapeutic (PDT) effects on MCF-7 cancer cells. The PS loading of 5-ALA was found to be 83% with an average hydrodynamic size and z-potential of 146 ± 0.8 nm and −6.40 mV respectively for FA-Au/PAA-ALA JNPs. The in vitro PDT study of the JNPs on MCF-7 breast cancer cells under 636 nm laser irradiation indicated the cell viability of 24.7% ± 0.5 for FA-Au/PAA-ALA JNPs at the IC50 value of 0.125 mM. In this regard, the actively targeted FA-Au/PAA-ALA JNPs treatment holds great potential for tumour therapy with high cancer cell-killing efficacy.