2.6.2 Fourier Transform Infrared – Attenuated total reflection (FTIR-ATR)
The spectrum of a small portion of eSF hydrogel at 14% was measured by FTIR-ATR spectroscopy at days 1, 3 and 7 (Equinox 55, Bruker Optics Inc., USA) in the range of 500–4500 cm−1.