Development of a cleaning in place protocol and repetitive application of Escherichia coli homogenate on STREAMLINE (TM) Q XL

An optimization of a cleaning in place (CIP) protocol has been performed fo r STREAMLINE(TM) Q XL separation medium using homogenised Escherichia coli as sample. The effectiveness of the different cleaning protocols was tested by analysing the content of fatty acids, phosphorus compounds and amino ac ids in STREAMLINE(TM) Q XL. Additionally, RAMAN and FT-IR measurements were used to verify the degree of contamination of separation medium. From the results of the optimization experiments, a cleaning procedure was suggested and subsequently tested with 50 repetitive applications. The study shows t hat of the different agents tested, 1 M NaOH is the most efficient cleaning solution and that long contact time (similar to 8 h) with 1 M NaOH is impo rtant. An additional cleaning step with 30% 2-propanol (v/v) is also recomm ended for E. coli samples. (C) 2000 Elsevier Science Ltd. Ail rights reserv ed.