2.7. Raman Spectra Instrument and Settings
The Raman spectra were measured using TruScan™ RM (TSRM) Handheld Raman analyzers equipped with the embedded TruTools™ chemometrics software package (Thermo Fisher Scientific). The device is a direct dispersive Raman that uses a 785-nm laser excitation wavelength. Its average spectral resolution varies between 8 and 10.5 cm−1, and the Raman shift range is 250–2875 cm−1. The mAb product solutions were transferred to 4-mL glass vials, which served as the sample cells for Raman spectrum acquisition. The acquisition was executed in the vial holder to prevent interference from ambient light. The excitation used identical spectral acquisition settings: 250 mW, 5000 ms, and 3 coadds.