Circular dichroism spectroscopy (CD) was used to investigate the structural changes of the following formulations: F2 at 278 K and after being heated to 370 K (following a THz-TDS experiment); F4 at 278 K and after being heated to 410 K in glass vials in a dry hear block. We also analysed BSA powder (A7906, Sigma-Aldrich) as received from the supplier. All BSA formulations were dissolved in dH 2 O and diluted to a concentration of 3 4 µm before analysis by CD. Protein concentration was calculated by measuring absorbance at 280 nm on a Nanovue spectrophotometer (GE Healthcare, Uppsala, Sweden) using the extinction coefficient of 43, 824 M 1 cm 1 . For formulations containing mAb1, F6 was analysed at 278 K and after being heated to 330 K. F7 was analysed at 278 K and after being heated to 370 K in glass ivals in a dry heat block. All NOP109 formulations were dissolved in dH 2 O and diluted to a concentration of 1 µm, calculated using the extinction coefficient of 207, 360 M 1 cm 1 . Samples were analysed in a 1 mm cuvette at a temperature of 303 K. CD spectra were acquired using a JASCO J-810 spectropolarimeter (Jasco Inc, Easton, MD, USA). Spectra were recorded over the spectral range of 250 190 nm, with a resolution of 0.5 nm, a continuous scan at 50 nm min 1 , and a bandwidth resolution of 1 nm. 10 accumulations were obtained for each sample and each experiment was repeated three times. CD spectra of dH 2 O were recorded and subtracted from each sample spectrum. Mean residue ellipticity was calculated using Equation , where [✓] is the mean residue ellipticity ( cm 2 dmol 1 ), ✓ obs the observed ellipticity, l the path length (mm), c the molar concentration (M) and n the number of residues (583 amino acids for BSA and 1330 for mAb1).