Abstract
Purpose:
Raman spectroscopy is a non-invasive method for analysis of biological molecules. We had been working on the molecular change in lens following age by Raman spectroscopy. As recent spectrometer and laser technology advance, Raman spectrum of biological tissue might be determined with weak laser irradiation and short time period. This is the basic research for clinical quantitation of cataract formation. We report the results of Raman spectra in rat lens and cataract surgery perfusion sample by using portable Raman spectrometer.
Methods:
1) Sprague-Dawley rat (7-week-old) was anesthetized with pentobarbital sodium (50 mg/kg, i.p.), fixed a head and determined Raman spectrum of rat lens by portable Raman spectrometer (ProRaman-L, Enwave Optronics Inc., USA): applied a 785 nm laser with 130 mW, acquisition time 30 seconds.<br /> 2) We collected perfusion samples at cataract surgery by phacoemulsification and aspiration. Raman spectra of the perfusion samples which include lens and the perfusion liquid as control were determined by portable Raman Spectrometer. This protocol was approved by Showa University Medical Ethics Committee.
Results:
1) The Raman spectra of rat lens showed a band at 3300 cm-1 due to an OH stretching mode and bands at 2935 cm-1 and 3065 cm-1 assigned to crystallin CH group. 2) The Raman spectra of the perfusion samples with ultrasonic fragmentation lens showed same bands assigned to lens protein without fluorescein disturbance.
Conclusions:
These results suggest that Raman spectra of cataract may be measurable by using potable Raman spectrometer in clinic. We will measure Raman Spectra of human nucleated lenses and nucleated eyes, will cooperate with development of spectrometer and laser irradiation device, and lead to clinical use.