Non-Invasive Tumor Therapy with Indocyanine Green and Paclitaxel Doubly Loaded Nanoparticles Using Photoacoustic Imaging

Photoacoustic imaging is the latest promising diagnostic tool with many advantages, such as high spatial resolution, deep penetration depth, and use of non-ionizing radiation. Tumor therapy using visual guidance of photoacoustic imaging has been recently highlighted for personalized and effective tumor therapy. The goal of this study was to develop a nano-medicine tool for simultaneous photoacoustic imaging-based diagnosis and chemotherapy. Here, indocyanine green and paclitaxel doubly-loaded human serum albumin nanoparticles (IPHSA-NPs) were developed as photoacoustic imaging-based theragnostic nano-medicines. The IPHSA-NPs were on average 188.14 +/- 42.82 nm in diameter. The IPHSA-NPs were taken up by cancer cells efficiently, resulting in effective anti-cancer activity (50% less cell viability with 200 nM of paclitaxel for 6 h compared to control). The IPHSA-NPs sufficiently demonstrated photoacoustic intensity in the near infrared region at a wavelength of 800 nm. The photoacoustic intensity of IPHSA-NPs was 1.5 times stronger than hemoglobin, an endogenous photoacoustic contrast molecule. In addition, both hypodermically and intravenously administered IPHSA-NPs provided sufficient photoacoustic contrast signal intensities in in vivo over 24 h. Finally, intravenously administered IPHSA-NPs successfully accumulated in the tumor region, resulting in high photoacoustic contrast intensity. In conclusion, IPHSA-NPs are capable of photoacoustic-based cancer diagnosis and chemotherapy.