In vitro Raman spectroscopy of healthy mammals crystalline lenses

The crystalline lens is a transparent biological material, and a complex inhomogeneous optical element in the vision system of mammals. It is a fiber cell structures [1]. Approximately 90% of the fiber cells composition are proteins responsible for the high refractive index of the lenses. This paper presents Raman spectroscopy as a tool for identification of the proteins and further diagnostic of disease in the lenses. Would all mammal lenses be made of the same protein? This is the question motivating this work. Raman spectroscopy is a rapid and non-destructive optical method for providing chemical information on molecular structures [2], and has been successfully applied to a variety of biological systems [2,3]. Our aim here is to investigate the protein average distribution in the lenses of distinct mammals by following main differences in the Raman spectral signature. The Raman signatures of healthy crystalline lenses from canine, mouse, pig, rabbit and horse were characterized in vitro. The results indicate that there are no substantial differences at all animals studied.