Removal of Endotoxin and Bacteria using the ELGA LabWater PURELAB® Chorus 1 fitted with a Point of use Filter (LC134 /LC145) or Biofilter (LC197)

Significance of the topic

Biological impurities such as bacteria and endotoxins can compromise biochemical assays, cell culture, IVF and genetic analyses.
Ultrapure water free of these contaminants enhances the reliability and reproducibility of sensitive life-science applications.

Objectives and Study Overview

This study evaluates the performance of the PURELAB Chorus 1 Life Science system equipped with point-of-use filters (LC134/LC145) or a Biofilter (LC197) for removal of endotoxins and bacteria from water.
Key goals include verifying endotoxin removal efficiency, bacterial rejection and assessing filter rinsing behavior under challenging conditions.

Methodology and Instrumentation

The PURELAB Chorus 1 Life Science system combines reverse osmosis and UV recirculation to minimize microbial growth.
Final purification stages used:

• Point-of-use filters: LC134 and LC145
• Biofilter: LC197 with positively charged media

Endotoxin removal was tested by challenging filters with lipopolysaccharide at increasing concentrations up to over 90 EU/ml and a total load near 800 000 EU.
Bacterial challenge used purified water inoculated with bacteria cultured in peptone water, followed by membrane filtration assays for total viable counts.
Total Organic Carbon (TOC) and resistivity rinse-up profiles were compared between the Biofilter and a standard ultrafilter at 1 L/min flow rate.

Key Results and Discussion

• Endotoxin Removal: Biofilter reduced endotoxin levels below detectable limits (<0.001 EU/ml), achieving log reductions >5 across all challenge levels.
• Bacterial Rejection: Both point-of-use filters and the Biofilter achieved total viable counts <0.001 CFU/ml, corresponding to log reductions >7 from feed levels up to 3.5 CFU/ml.
• TOC Rinse-up: The Biofilter reached below 10 ppb TOC within 8 L of rinse water, while the ultrafilter required over 75 minutes to drop below 50 ppb, indicating lower initial leachable organics from the Biofilter.

These findings demonstrate the high efficiency and low contaminant release of the Biofilter and point-of-use filters when integrated into the PURELAB Chorus 1 Life Science system.

Benefits and Practical Applications

• Provides endotoxin- and bacteria-free water for PCR, cell culture, IVF, electrophoresis and other sensitive assays.
• Reduces risk of experimental artifacts and improves data quality.
• Rapid filter rinse-up enhances operational convenience and minimizes downtime.

Future Trends and Opportunities

Emerging applications in single-cell analysis, advanced molecular diagnostics and biopharmaceutical production will increasingly require ultrapure water free of biological contaminants.
Integration with real-time monitoring and automated sanitization could further optimize water quality management.

Conclusion

The PURELAB Chorus 1 Life Science system equipped with LC134/LC145 point-of-use filters or the LC197 Biofilter delivers ultrapure water effectively free of bacteria and endotoxins.
High log reduction rates, rapid TOC rinse-up and low impurity release make these filtration solutions well suited for critical life-science and biochemical applications.

References

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