Chloroaluminum Phthalocyanine Loaded Bovine Serum Albumin Nanoparticles as a Dual-Functional Nanoplatform for Sono-Photodynamic Cancer Therapy

Abstract

Chloroaluminum phthalocyanine (ClAlPc) loaded bovine serum albumin (BSA) nanoparticles (NPs) were synthesized as a dual-functional platform for photodynamic and sonodynamic therapies (PDT and SDT). ClAlPc loading did not disturb the morphology of the BSA NPs. Their spherical structure, with a size around 200 nm, was preserved upon ClAlPc loading (1 %w/w). Singlet oxygen productions in the presence of ClAlPc loaded BSA NPs or free ClAlPc were determined by ultraviolet absorption (UV-vis) spectroscopy and electron paramagnetic resonance (EPR) spectroscopy. While a slower rate of singlet oxygen formation rate after both PDT and SDT was detected by UV-vis measurements in the presence of ClAlPc loaded BSA NPs, EPR results showed a similar rate of singlet oxygen formation for both ClAlPc loaded BSA NPs and free ClAlPc. Confocal microscopy confirmed the efficient cellular uptake and perinuclear localization of the ClAlPc loaded BSA NPs in HCT-116 cancer cells. In vitro cytotoxicity studies demonstrated a dose and time dependent photo-and sonotoxic effects in the presence of ClAlPc loaded BSA. In particular, simultaneous application of light and ultrasound as sono-photodynamic therapy (SPDT) resulted in 15 % cell viability in the presence of ClAlPc loaded BSA NPs, which is much lower than individual PDT and SDT results, confirming the effect of the combination therapy on cell viability. In comparison, free ClAlPc reduced cell viability to 27 %. These findings suggest that ClAlPc loaded BSA NPs is a promising "one-for-two" nanoplatform for combined cancer therapy to reduce the limitations of both methods.