[Raman analysis of conformation changes of insulin solvent after being exposed to ELF pulsed electric field].

Raman spectra of insulin solvents are presented before and after being exposed to the pulsed electric field with extremely low frequency 50 Hz (ELF). The covalences of the molecule were not affected and the changes of some secondary bonds such as hydrogen bonds and salt bonds were observed. Detailed analysis of these spectra indicates that the alpha-helix of insulin molecule was destroyed after the exposure, which is proved by the shift of the peak of the amide I region toward higher wave number and by the appearance of several new peaks: 1561 and 1594 cm(-1). The disulfides were affected by the weaken alpha-helix, and their vibrational modes were changed. Meanwhile the hydrogen bonding between the dimer are broken down which leads to the increase in the peak intensities at 1002 and at 1602 cm(-1).