Raman spectroscopic study on Hela cells irradiated by X rays of different doses

Raman spectra are used for studying the structure and protein, nucleic acid, lipid, and carbohydrate contents, while cervical cancer cells irradiated by X rays of different doses are cultivated for 24 h. After irradiation by X rays, the following results are obtained. （1） Some 12-Gy groups move to the 1237-cm^-1 band in compared with the control group＇s 1240-cm^-1 band; after irradiation by 6-Gy X ray, the 1662-cm^-1 band of amide I has a blue shift of 10 cm^-1. The above two parts show that because of X ray irradiation, some proteins＇ random coil structures have transformed into β folding. （2） The 759-cm^-1 band disappear in the 6-Gy group; the 570-cm^-1 band of every group has a red shift, but the changes in intensity are different; the 1335-cm^-1 band in every group has a blue shift, and all their intensities increase. These show that although the 570-, 759-, and 1335-cm^-1 bands all belong to the tryptophan residue indole ring vibration, the molecular vibration energy structures which produce scattering lights are different. （3） The 786-cm^-1 band only has a blue shift of 3 cm^-1 in the 6-Gy group, and the non-hydrogen band of the phosphoric acid diester （O-P-O） increases. The frequency deviation of the 1089-cm^-1 band is erratic, and the bent symmetry stretch vibration conformation of phosphoric acid diester key （O=P=O） in the nucleic acid is complex. （4） The 1570-cm^-1 band has a blue shift, and its intensities all decrease, while the C=C conjugated duplet bond oxidizes, and the content of C=C decreases.     

利用拉曼光谱研究~(60)Co γ射线对EC9706细胞的辐射损伤

将EC9706细胞经不同剂量^60Coγ射线辐照后继续培养24 h。利用激光拉曼光谱分析EC9706细胞内部蛋白质、核酸、脂类等生物大分子的构象和含量变化。分析结果发现,各剂量组拉曼谱的峰强和频移与空白对照组之间存在较大的差异,主要表现是蛋白质酰胺Ⅲ带1 244 cm^-1谱带在中等剂量组（4、5Gy）β折叠结构向无规卷曲转化;色氨酸残基的吲哚环振动谱带1 341 cm^-1在各剂量组中出现不同程度的红移;782 cm^-1谱带在大剂量组（7、8Gy）红移2～3 cm^-1,说明大剂量γ射线辐照导致DNA中的磷酸二酯（O—P—O）基团的非氢键化程度增强。脂类的CH2和CH3弯曲振动谱带1 446 cm^-1在2、4Gy组蓝移4 cm^-1,其他剂量组频移不大,这与60Coγ射线对EC9706细胞的生物膜造成一定损伤有关。拉曼特征峰在不同剂量组中的变化,为进一步研究60Coγ射线辐照损伤EC9706细胞的最佳剂量提供了一定实验依据。