Gold nanorod-mediated near-infrared laser ablation: in vivo experiments on mice and theoretical analysis at different settings

摘要

Purpose: The aim of the present study was the in vivo assessment of the effects of gold nanorod (AuNR)-mediated laser ablation (LA) of flank xenograft tumours. We investigated: the differences between intra-tumoural (TsubIT/sub) and surface tumoural temperature (TsubS/sub); the influence of AuNRs concentration and laser power (P) on both these temperatures and on tumour regression. Lastly, experimental data were used to validate a theoretical model developed to predict the effects of AuNR-mediated LA. Materials and methods: Thirty-two nude mice were treated using near-infra-red light at two P, 3 d after injecting increasing AuNR doses. TsubIT/sub and TsubS/sub were recorded during the procedure by two thermocouples, one located within the tumour and the other one on the skin adjacent to the tumour. Tumour regression was assessed 2 d after near-infra-red exposure via Xenogen imaging. A three-dimensional temperature map was obtained by finite element modelling. Results: TsubIT/sub and TsubS/sub difference is substantial when AuNRs are injected. Moreover, the maximum temperature reached is strongly influenced by both P and AuNR concentration. Tumours heated above 55?°C experienced regression. Good agreement between experimental and theoretical TsubIT/sub was found (maximum difference of 4?°C). Conclusions: Data show significant influence of P and AuNR concentration on the temperatures reached during AuNR-mediated LA of solid tumours. TsubS/sub and TsubIT/sub difference increases with AuNRs concentration. Simulated temperatures agree quite well with experimental data. Together, these results represent the first step towards a rationally designed strategy to select the most promising laser settings and AuNRs concentration to improve solid tumour treatment outcomes.