Micro-Raman spectroscopy of single leukemic cells

The Raman spectra from leukemic cell line （HL60） and normal human peripheral blood mononuclear cells （PBMCs） are obtained by confocal micro-Raman spectroscopy using near-infrared laser （785 nm） excitation. The scanning range is from 500 to 2000 cm^-1. The two average Raman spectra of normal PBMCs and carcinoma cells have clear differences because their structure and amount of nucleic acid, protein, and other major molecules are changed. The spectra are also compared and analyzed by principal component analysis （PCA） to demonstrate the two distinct clusters of normal and transformed cells. The sensitivity of this technique for identifying transformed cells is 100%.     

激光偏振性对亚心形扁藻生物效应的影响

实验研究了偏振与非偏振激光对亚心形扁藻的促长作用、叶绿素含量以及色素粗提物吸收光谱等生物学效应的影响.采用488 nm,70 mW输出功率的氩激光,辐照哑心形扁藻,隔天取样进行细胞计数,培养至第6天提取叶绿素,测量叶绿素含量并扫描叶绿素的吸收光谱.实验结果表明,偏振激光与非偏振激光辐照对藻细胞密度、生长速率的促长作用区别不显著;偏振性与否对叶绿素含量的累积没有明显的区别;激光偏振性对色素粗提物的吸收光谱没有影响.激光偏振性与否均可对亚心形扁藻的生物效应产生有效的作用,激光偏振性与激光生物效应关系的研究有待于进一步深入.