WaterThe Essence of the Lab

Importance of the Topic

Water is the most commonly used and critical reagent in laboratories, impacting the accuracy and reproducibility of techniques from chromatography to cell culture.

Goals and Overview of the Study

This whitepaper by ELGA LabWater reviews the nature of water impurities, outlines international purity standards, and presents available purification technologies. It further matches water grades to typical lab applications and offers practical guidance on system installation and monitoring.

Methodology and Instrumentation

The report categorizes water impurities—suspended particles, dissolved ions, organic compounds, gases, and microorganisms—and describes measurement metrics such as resistivity, conductivity, TOC, turbidity, and bacterial counts. It then surveys pretreatment methods (depth filters, activated carbon) and advanced purification steps including reverse osmosis, ion exchange, electrodeionization, micro- and ultrafiltration, UV sterilization, distillation, and degassing. Storage and in-line purity monitoring are also covered.

Main Results and Discussion

Impurities at trace levels can compromise assays: organic and particulates affect HPLC baseline and column life; bacterial contaminants disrupt blotting techniques, PCR, and cell cultures; dissolved gases alter pH and chromatographic performance; ionic imbalances impair electrophoresis and spectrometric accuracy. The whitepaper quantifies recommended purity grades (Type III to Type I+) for over thirty laboratory methods.

Benefits and Practical Applications

Selecting the correct water grade prevents erroneous data, reduces instrument downtime, and ensures compliance with regulatory and quality standards. Tailored purity levels enhance cost efficiency by avoiding over-specification for noncritical tasks and safeguarding high-end analyses.

Used Instrumentation

• Depth filters and activated carbon cartridges for suspended solids and chlorine removal
• Reverse osmosis membranes to eliminate up to 95% of ions and organics
• Ion exchange and electrodeionization modules for final deionization
• Micro- and ultrafiltration membranes to remove bacteria, endotoxins, and colloids
• UV lamps for microbial control and TOC reduction
• Distillation units for long-term storage with high purity
• Degassing membranes to strip dissolved gases
• Reservoirs with recirculation systems and vent filters to maintain purity during storage

Future Trends and Opportunities

Emerging developments include graphene-based membranes offering ultra-fast ion removal, increased instrument sensitivity down to parts-per-trillion, and new molecular biology assays (single-molecule PCR, microRNA analysis) demanding apyrogenic ultra pure water. The food, nanomaterials, and environmental sectors will drive further innovation in purification technology.

Conclusion

Understanding water impurity sources and matching purification methods to application requirements is essential for high-quality, reproducible laboratory results. Integrating robust pretreatment, purification, storage, and monitoring ensures that water quality supports the most demanding analytical and biological workflows.

References

1. European Commission DG ENV. Study on Water Performance of Buildings. Final Report, 2009.
2. ELGA LabWater. Pure LabWater Guide.
3. Whitehead P. Ultra-pure Water for HPLC. Laboratory Solutions, 1998.
4. ELGA LabWater. Application Note: Type I Ultra Pure Water Crucial for HPLC and UHPLC.
5. Whitehead P. Importance of Pure Water in Modern Ion Chromatography. Lab Manager Magazine, 2010.
6. Mostofa KMG et al. Dissolved Organic Matter in Natural Waters. Environmental Science and Engineering, 2013.
7. Bar-Ilan O et al. Nanotoxicity of Titanium Dioxide: Fish Mortality at ppb Levels. Environmental Science and Technology, 2013;47(9):4726–7443.
8. University of Manchester. Graphene Filters for Water Purification, 2013.
9. ELGA LabWater. Water: The Essence of the Lab. Whitepaper.