Monitoring of Thermal Dose During Ablation Therapy Using Quantum Dot-Mediated Fluorescence Thermometry

作者:Bensalah Karim; Tuncel Altug; Hanson Willard; Stern Joshua; Han Bumsoo; Cadeddu Jeffrey*
来源:Journal of Endourology, 2010, 24(12): 1903-1908.
DOI:10.1089/end.2010.0110

摘要

Purpose: The objective of this study was to demonstrate the feasibility of quantum dot (QD)-mediated fluorescence thermometry to monitor thermal dose in an in-vitro thermal ablation zone generated by laser-heated gold nanoshells (LGNS). Materials and Methods: Hyperthermic cell death of human prostate cancer cell line (PC-3) was determined after various heating settings and correlated to the thermal conditions using an Arrhenius model prior to LGNS ablation. PC-3 cells with gold nanoshells (GNS) and QDs were exposed to a near-infrared laser and QD excitation light. When the cells were heated by GNS, local temperature was measured using the temperature-dependent fluorescence intensity of QDs. Using the predetermined Arrhenius model, the thermal dose (i.e., cell death of PC-3 cells) by LGNS was estimated with local temperatures measured with QD-mediated thermometry. The estimated thermal dose was confirmed with calcein-acetoxy-methylester viability assay. Results: For PC-3 cell line, the activation energy and frequency factor of the Arrhenius model were 86.78 kcal/mol and 6.35x10(55) Hz, respectively. During LGNS ablation of PC-3 cells, QD-mediated temperature measurement showed that the temperature of the laser spot increased rapidly to similar to 58 degrees C+/-4 degrees C. The estimated thermal dose showed that cell death reached to similar to 90% in 120 seconds. The death cell zone observed after staining corresponded to a peak area of the temperature profile generated after analysis of the QD fluorescence intensity. Conclusions: This study shows that the QD fluorescence thermometry can accurately monitor the PC-3 cell death by LGNS ablation. This approach holds promises for a better monitoring of thermal ablation procedures in clinical practice.

  • 出版日期2010-12