I have cleaned the S-300HR pre-packed column using the rigorous cleaning steps given in the instructions. (1/4 column volume 0.5M NaOH, followed by 4CV of water, 1/2 CV of 30% isopropanol, again followed by 4CV of water, then with 1CV of pepsin in 0.1M acetic acid, 0.5M NaCl, then with 1/2 CV of 0.2M NaOH, then again with 4 CV of water). Before washing, the pressure was 19psi at 0.100ml/min. Even after cleaning, the pressure is still 13-14psi at 0.150ml/min. Can I use the column for my experiment?