Challenges and advances in cleaning ultrafiltration membranes used in bioprocessing
Proposed is a method to evaluate formulated cleaning agents commonly used for cGMP cleaning applications to demonstrate they may also be suitable for cleaning select ultrafiltration (UF) membranes. Feasibility testing was performed to compare cleaning methodologies, demonstrating a correlation to lab evaluations on a representative surface. Membrane cleaning efficiency was assessed where results indicate use of formulated detergents leads to increased cycle lifetime and an average of 40% less water usage for rinsing.
Ultra-filtration membranes are used extensively in biopharmaceutical operations. A typical purification process may incorporate two to six UF steps throughout the downstream process. Customarily, these membranes are cleaned using 0.1 – 0.5 N Sodium hydroxide (NaOH), dilute solutions of Sodium hypochlorite (NaClO) and elevated temperatures. Enzymatic cleaning is relatively safe but can be expensive (1,2). Solutions are chosen due to recommendations from the membrane manufacturer or what has been historically performed on site.
The cleaning process is challenging and does not consider the residue being cleaned, only the compatibility of the cleaning agent on the membrane. By not focusing on the residue and how to effectively remove it from the surface, the end user is left with an inefficient cleaning process at best. Inefficient cleaning of UF membranes leads to a reduction in membrane cycles, or re-use rate, increased water consumption, lower product yields, increased risk for microbial contamination and an increase in concentration/ultra-filtration processing times.
To effectively c ...