BACKGROUNDTo observe the effects of photodynamic therapy (PDT) on human lung adenocarcinoma cell line A549 in vitro.

METHODSHuman lung adenocarcinoma cell line A549 was used to investigate the killing role of PDT with hematoporphyrin derivative (HPD) as photosensitizer and semiconductor successive laser as light source. The cultured cell was treated with different concentrations of HPD and different do-sages of laser, then MTT colorometric assay was applied to measure the OD492.

RESULTS5 mg/L of HPD was confirmed no effect. 10 mg/L of HPD could produce a marked therapeutical effect under the condition of same laser dosage. When the concentration of HPD was increased, the effect was not risen obviously. 10 J/cm² of laser could lead OD492 to decrease to platform under the condition of same HPD concentration. So the killing effect was saturated when the PDT parameters were selected as 10 mg/L of HPD and 10 J/cm² of laser. Under the same laser capacity density of 10 J/cm², A549 cells were exposured to three different duty-time fabrications which were 214 mw×10 min, 428 mw×5 min and 714 mw×3 min.The outcomes showed that OD492 had no statistical difference.

CONCLUSIONSPDT has a significant killing effect on human lung adenocarcinoma cell line A549. 10 mg/L of HPD and 10 J/cm² of laser were the best parameters of this experiment. The PDT effect is not influenced by different duty-time fabrications under the best laser capacity density.