Comparison between optical measurements made from natural and frozen samples at optical clearing

Abstract

To determine the differences between the optical clearing effects created by ethylene glycol in fresh and frozen samples, we have performed several measurements from samples in both conditions. Fresh samples were used after animal sacrifice and frozen samples were kept at -20 degrees C for 72 hours. The different measurements performed with samples from both cases were total transmittance, collimated transmittance, total reflectance and specular reflectance. Considering, for instance, collimated transmittance measurements, we have verified that the spectra measured from both samples before adding the solution present different levels of collimated transmittance. The time-dependence evolution of the collimated transmittance spectrum is similar between both cases of samples, but since they present different levels of "natural" transmittance, the optical clearing effect is observed at different levels if we compare between fresh and frozen samples.