Related Experiment Video
Updated: Aug 9, 2026
An In Vitro Approach to Photodynamic Therapy
Published on: August 17, 2018
The influence of temperature on photodynamic cell killing in vitro with 5-aminolevulinic acid
Asta Juzeniene1, Petras Juzenas, Irena Bronshtein
1Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, N-0310 Montebello, Oslo, Norway. asta.juzeniene@klinmed.uio.no
Abstract:
Cell survival was investigated after exposing cells in vitro to different temperatures before or after photodynamic therapy with 5-aminolevulinic acid. The photodynamic process was found to be temperature dependent. Cells exposed for 1h to 41 degrees C before light exposure or to 7 degrees C after light exposure showed decreased survival. Furthermore, the photobleaching rate of protoporphyrin IX in the cells was found to increase with increasing temperature during the light exposure. Thus, the photodynamic effect with 5-aminolevulinic acid may be enhanced by heating the tumour area before, and by cooling it immediately after the treatment.
