Thermal and UV radiation effects on dynamic viscosity of gelatin-based riboflavin solutions

Two samples of gelatin based solutions which consist of 2% of biocompatible gelatin content and 0.5% of UV sensitive riboflavin sample were constituted at the room temperature. During the preparation process, the solutions were protected from the light since the UV sensitive riboflavin content acts as an onset initiator agent of photo-crosslinking reaction in case of light radiation. To clarify the effect of UV radiation on viscosity of specimens at different temperature range, one of the prepared specimens were radiated to UV for a while at the wavelength value where the biologically suitable one of the peaks is determined in UV/visible absorbance. Afterwards, the viscosity measurements of UV radiated and un-radiated gelatin based riboflavin solutions were performed with the speed value where the most reliable torque value is shown, at different temperature values. Experimentally, it was understood that there was no change in fluid types as a result of UV radiation, however; viscosity values of both solutions diminished at the elevated temperature levels. The viscosity of pure gelatin content was lower than gelatin-RF content and addition of RF increased the viscosity. All samples were mathematically modeled by Boltzmann equation as each specimen obeyed Arrhenius model. (C) 2016 Elsevier B.V. All rights reserved.