Laboratory water A key reagent for experimental success

Significance of the topic

Laboratory water is a fundamental reagent across life science, analytical and clinical laboratories. Despite its ubiquity, variable feedwater sources and a broad spectrum of contaminants—particles, inorganic ions, organic compounds, microorganisms and dissolved gases—pose significant risks to experimental accuracy, reproducibility and instrument performance.

Objectives and overview of the paper

This white paper by ELGA LabWater reviews water quality requirements for laboratory workflows, outlines international and industry standards, classifies laboratory water into practical grades, compares in-house purification with bottled supplies and presents guidance for selecting and operating a reliable water purification system.

Methodology and instrumentation

Water purification solutions combine a sequence of technologies to remove specific contaminant classes:

• Primary pretreatment: activated carbon and depth filters to protect downstream components.
• Reverse osmosis (RO) to eliminate dissolved ions, colloids and bacteria.
• Ion exchange (IX) and electrodeionisation (EDI) for ultrapure resistivity and low total organic carbon (TOC).
• Ultraviolet (UV) oxidation for bacterial control and organic reduction.
• Micro- and ultrafiltration to exclude particulates and endotoxins at the point-of-use.
• Degassing modules to strip dissolved gases that affect pH and chromatographic baselines.

Instrumentation used

The PURELAB® range integrates RO membranes, IX resins, UV lamps, TOC monitors and recirculation loops. Centra® systems offer high-volume distribution, while Medica® products deliver Clinical Laboratory Reagent Water (CLRW) to diagnostic analyzers.

Key results and discussion

Impurities interfere in numerous applications:

• HPLC and ion chromatography: ionic and organic leaks distort baselines and retention times.
• Spectroscopy and mass spectrometry: trace metals and organics bias quantification at part-per-trillion levels.
• Molecular biology: nucleases, endotoxins and cations inhibit PCR, blotting and cell culture.
• Histology and immunohistochemistry: microbial byproducts and metal ions generate staining artefacts.

Classification schemes (ASTM, ISO, CLSI) define Types I–IV or Grades 1–3, but ELGA simplifies this into Types I+, I, II+, II and III, aligning resistivity, TOC and microbial limits with typical laboratory tasks.

Benefits and practical applications of the method

Installing an in-house purification system ensures:

• Consistent water purity matching each technique’s needs.
• Cost savings over bottled supplies, especially for high-throughput labs.
• Reduced plastic waste and carbon footprint compared with pre-bottled grades.
• On-demand production, minimal downtime and real-time purity monitoring.

Future trends and possibilities

Advances focus on modular, scalable systems with IoT-enabled monitoring, automated sanitization and self-servicing cartridges. Emerging low-energy RO and green regeneration chemistries further reduce environmental impact. Integration with laboratory information management systems (LIMS) will improve traceability and compliance.

Conclusion

Appropriate laboratory water quality is essential for robust, reproducible data. ELGA’s classification framework and multi-stage purification technologies provide a cost-effective, scalable approach to meet diverse research and clinical requirements. By selecting the right system, laboratories can maximize data integrity, operational efficiency and environmental stewardship.

Reference

1. Rana Nabulsi & Mousa A. Al-Abbadi; Laboratory Medicine, 45(4):e159–e165 (2014).
2. Ander EL et al.; Environmental Geochemistry and Health, 38(6):1313–1332 (2016).
3. Master S, Welter GJ & Edwards M; Environ Sci Technol, 50(10):5269–5277 (2016).
4. ASTM D1193-06; Standard Specification for Reagent Water (ASTM Int., 2006).
5. ISO 3696:1987; Water for analytical laboratory use – specification and test methods (ISO, 1987).
6. CLSI GP40, 4th Edition; Preparation and Testing of Reagent Water in the Clinical Laboratory (CLSI, 2018).
7. Urbina MA, Watts AJR & Reardon EE; Nature 528:479 (2015).
8. ELGA Application Note: Type I ultrapure water for HPLC/UHPLC.
9. Whitehead P; Lab Manager Magazine, November 2010.