2.3. High performance size exclusion chromatography
High performance size exclusion chromatography (HP-SEC) was applied for evaluating the capability of 2D-AEC×SEC for production NSP-free FMD vaccine, as well as the most important factors affecting the quality of the final products, integrity of active ingredient of vaccine, by monitoring fingerprint HPLC elution profiles of the purified FMDV fractions throughout the purification procedure as describe before (Bagheri et al., 2018). Briefly, HP-SEC analysis was performed on a Knauer HPLC system equipped with a photodiode array detector (PDA) set up at 280 nm and controlled by EZChrom Elite software. The HPLC conditions included Ultrahydrogel Linear (300 × 7.8 mm, I.D.) analytical column from Waters (NJ 07054, US), solvent system consisting of 50 mM phosphate buffer with pH 7.2 containing 100 mM Na2SO4 as the mobile phase, the flow rate of 0.6 mL/min, and the injection volume of 100 µl.