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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 \beta 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.

Fourier transform infrared spectroscopy (FTIR) was employed to study the human epidermis larynx carcinoma cell lines (Hep-2) which were irradiated by different doses of X-ray. The results show that (1) the irradiation of X-ray damages the structure of the CH3 groups of the thymine in DNA, which restrains the reproduction of Hep-2 cells effectively, (2) the 8 Gy dose of X-ray irradiation changes the framework and the relative contents of some proteins, lipids and the nucleic acid molecules intercellular in the greatest degree, and (3) the 8 Gy dose of X-ray irradiation is the best irradiation dose for lowering the degree of the cancerization of Hep-2 cells according to the criteria for the degree of the cancerization reported recently. Meanwhile, the apoptosis of these cells were detected by using flow cytometry (FCM) primarily. It shows that the apoptotic ratio of the Hep-2 cells depends on the irradiation dose to some extent, but is not linearly. And the apoptotic ratio of the 12 Gy dose group is the maximum (20.36%), but the apoptotic ratios of the 2 to 8 Gy dose groups change little.