Photothermal ablation of pancreatic cancer cells with hybrid iron-oxide core gold-shell nanoparticles

Yang Guo,1 Zhuoli Zhang,1 Dong-Hyun Kim,1,5 Weiguo Li,1 Jodi Nicolai,1 Daniel Procissi,1 Yi Huan,2 Guohong Han,3 Reed A Omary,1,4,5 Andrew C Larson1,4,5 1Department of Radiology, Northwestern University, Chicago, IL, USA; 2Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi'an, People's Republic of China; 3Department of Digestive Interventional Radiology, Xijing Hospital, Fourth Military Medical University, Xi'an, People's Republic of China; 4Department of Biomedical Engineering, Northwestern University, Chicago, IL, USA; 5Robert H Lurie Comprehensive Cancer Center, Chicago, IL, USA Purpose: Photothermal ablation is a minimally invasive approach, which typically involves delivery of photothermal sensitizers to targeted tissues. The purpose of our study was to demonstrate that gold nanoparticles are phagocytosed by pancreatic cancer cells, thus permitting magnetic resonance imaging (MRI) of sensitizer delivery and photothermal ablation. Patients and methods: Iron-oxide core/gold-shell nanoparticles (GoldMag®, 30 nm diameter; Xi'an GoldMag Biotechnology Co, Xi'an, People's Republic of China) were used. In a 96-well plate, 3 × 104 PANC-1 (human pancreatic cancer cell line) cells were placed. GoldMag (0, 25, or 50 µg/mL) was added to each well and 24 hours allowed for cellular uptake. Samples were then divided into two groups: one treated with photothermal ablation (7.9 W/cm2) for 5 minutes, the other not treated. Photothermal ablation was performed using laser system (BWF5; B&W Tek, Inc, Newark, DE, USA). Intraprocedural temperature changes were measured using a fiber optic temperature probe (FTP-LN2; Photon Control Inc, Burnaby, BC, Canada). After 24 hours, the remaining number of viable cells was counted using trypan blue staining; cell proliferation percentage was calculated based on the total number of viable cells after treatment compared with c