Toyopearl and TSKgel 5PW resins, with the exception of some affinity resins, can withstand sanitization conditions commonly used in large scale manufacturing. A general used cleaning procedure is as follows: 3- 5 CV of 0.1-0.5 M sodium hydroxide, followed by 3-5 CV of 0.5-1 M sodium chloride before column equilibration. Toyopearl and TSKgel resins can withstand caustic for well up to 8 hours at a time. Be sure to operate at reasonable flowrates to avoid over pressuring as the resin will swell in the presence of caustic. Maximum pressure limit for Toyopearl resins is 3 bar/ 45 psi and for TSKgel 5PW resin is 20 bar/ 300 psi.
In some cases, protein may be tightly bound to the resin. In cases where protein is bound ionically, follow the hydroxide wash with 5 CV of water then 3-5 CV of 0.1-0.5 M hydrochloric acid before washing with salt. In cases where protein is bound hydrophobically to either HIC or SEC resin, wash the resin with 3-5 CV of water, followed by 3-5 CV of 20% methanol or acetonitrile. Rinse with 3-5 CV of water before following the general use cleaning procedure.
In regards to the affinity resins, the AF-Chelate resin may be cleaned following the general use cleaning procedure while the more ligand sensitive resins should be cleaned with any combination of salt, chaotrope (Urea/ Guanidine HCl), or detergents (Triton/ Tween). In extreme cases of tightly bound protein, the AF Heparin may be cleaned with 2 CV of 0.5 M sodium hydroxide as a last resort.