CONICET | Buscador de Institutos y Recursos Humanos

Samples of oriented collagen biomembranes were exposed to solar irradiance incident at Rosario Astronomical Observatory, Argentina, with maximum UV-index in the range of 12. The accumulated dose for the total period (measured with a YES biometer) was 85KJ/m2.The normal biofilm transmittance in the 180-500 nm range was measured in laboratory using a Metrolab/2500 UV-visible spectrophotometer. The percentage modification as function of the applied dose is rather linear, with values (-0.26±0.02), (-0.11±0.02) and (-0.020±0.022) %/(KJ/m2) for the UVC* (250-290 nm), UVB (290-320 nm) and UVA (320-400 nm) ranges, respectively. The aging effect was also analyzed during 15 months, employing a non-exposed sample. The data were approximated by a Boltzmann function. It was also studied the solar transmittance with an Avantes spectroradiometer, exposing 9 samples to the intense Sun. The mean transmittance decreases with decreasing wavelength in the UVA-Visible-near IR range, from 0.950±0.005 at 812 nm to 0.59±0.05 at 320 nm.