基于皮秒时间分辨的癌细胞荧光寿命研究

研究了用于癌症诊断与治疗的光敏剂血卟啉(hematoporphyrin derivative，HPD)的超快光动力学过程，采用超短脉冲激光光谱技术和皮秒时间相关单光子计数系统，测量了经血卟啉培养的活体癌细胞与正常细胞的皮秒时间分辨荧光光谱及荧光峰值强度随时间衰变曲线，观测到：癌细胞与正常细胞样品荧光寿命的快成分分别为150和300 ps;癌细胞与正常细胞的荧光峰值强度经12 h分别衰减10%和55%。经对测量所得的荧光衰减曲线进行分析，计算出癌细胞与正常细胞的荧光寿命分别为824和1798 ps;血卟啉在癌细胞与正常细胞样品中滞留时间分别为17天和6天。结果表明癌细胞与正常细胞对血卟啉亲和性及对血卟啉滞留的稳定性有显著差异，测量结果确认了荧光光谱技术诊断与治疗癌症的可行性，并对实时监测生物样品微弱超快荧光具有重要的指导意义和临床应用价值。

Study of Cancer Cells Fluorescence Lifetime Based on Picosecond Time Resolution

The object of the present study was the ultrafast photodynamic processes of hematoporphyrin derivative(HPD) for diagnosis and therapy of cancer.Time-resolved fluorescence spectra of cancerous and normal cells were measured using an ultrashort pulse laser spectral technique and picosecond time-correlated single-photon counting system.The fast part of cancerous and normal cells fluorescence decay was approximately 150 and 300 ps,the fluorescence peak intensity of cancerous and normal cells decayed about 10% and 55% in 12 hour,the lifetime of cancerous and normal cells was about 824 and 1 798 ps by calculating date of fluorescence decay,and HPD stay time was about 17 and 6 days in the cancerous and normal cells sample respectively.The data show that cancerous cells were greatly intimate with HPD.The results obtained can be used as an important basis for the diagnosis of cancer based on ultrashort pulse laser spectral technique.The results will contribute to feebleness ultrafast fluorescence of biology sample for real time measurement.