Laboratory water A key reagent for experimental success

Significance of the Topic

Laboratory water is a fundamental reagent across research, clinical diagnostics and industrial analytics. Its solvent properties mean it can carry a wide array of contaminants from tap water sources, introducing variability and risk into sensitive experiments. Ensuring the appropriate purity level of laboratory water underpins reproducibility, accuracy and cost-effectiveness, while reducing downtime and environmental impact.

Objectives and Study Overview

This white paper presents a structured approach to understanding, classifying and sourcing laboratory water. Drawing on over eight decades of ELGA’s water purification expertise, it aims to:

• Identify common waterborne contaminants and their impacts on assays.
• Define international water quality standards and ELGA’s water grades.
• Compare in-house purification systems with bottled water supply.
• Provide guidance on selecting, installing and maintaining a reliable water system.

Methodology and Instrumentation

The paper describes a multi-stage water purification workflow:

• Primary treatment: pretreatment filters and activated carbon to reduce particulates and chlorine.
• Membrane processes: reverse osmosis (RO) and degassing modules to reject dissolved inorganics and gases.
• Ion-removal: ion exchange (IX) and electrodeionization (EDI) for high resistivity and low ionic content.
• Microbial control: ultraviolet (UV) lamps and micro/ultrafiltration (MF/UF) to limit bacteria, endotoxins and colloids.
• Point-of-use polishing: final filters and real-time sensors monitor resistivity and total organic carbon (TOC).

Key instrumentation solutions include ELGA’s PURELAB®, MEDICA® and CENTRA® systems, offering modular configurations, automated dispensing, data logging and validation support.

Main Results and Discussion

Analysis of tap water contaminants highlights suspended particles, inorganic ions, dissolved organics, gases and microbes as potential disruptors of blotting, chromatography, spectroscopy, PCR and cell culture. Even trace impurities can lead to elevated baselines, shifted retention times or enzyme inhibition.

International standards (ASTM D1193, ISO 3696, CLSI) categorize laboratory water into grades or types based on parameters such as resistivity, TOC, bacterial count and endotoxin levels. ELGA refines these into Types III, II, II+, I and I+ and maps them to over 30 common applications ranging from glassware rinsing to ICP-MS.

A comparative evaluation shows that in-house systems provide:

• Continuous access to multiple purity grades.
• Lower long-term cost versus bottled water.
• Reduced plastic waste and transport carbon footprint.
• Real-time quality assurance and customizable workflows.

Common misconceptions—such as perceived high cost, maintenance complexity or space requirements—are addressed with data on modular design, remote monitoring and service networks.

Benefits and Practical Applications

Deploying an optimized water purification system delivers:

• Enhanced reproducibility and data quality in analytical and life-science assays.
• Operational efficiency: automated dispensing, alerts for consumable replacement and minimal hands-on maintenance.
• Cost savings through reduced bottled water procurement and waste disposal.
• Environmental sustainability via high water recovery, energy-efficient modules and less plastic usage.

Future Trends and Potential Applications

Emerging directions include:

• Integration with laboratory information management systems (LIMS) for traceable quality records.
• Advanced sensor technologies for multi-parametric, real-time monitoring (e.g., microbial, TOC, conductivity).
• IoT-enabled remote diagnostics and predictive maintenance.
• Modular platforms that scale with laboratory growth and evolving regulatory demands.
• Green innovations in resin regeneration and energy-efficient purification cycles.

Conclusion

Water purity is a critical determinant of experimental success. By matching water quality to application needs and selecting an in-house purification solution, laboratories can secure consistent results, reduce operating costs and minimize environmental impact. Partnering with a specialist provider ensures expert guidance from feedwater analysis through system validation and lifelong support.

Instrumentation Used

Key technologies employed in modern water purification systems:

• Reverse Osmosis membranes for broad contaminant rejection.
• Ion exchange and electrodeionization for ultrapure resistivity.
• UV oxidation for organic degradation and microbiological control.
• Micro/ultrafiltration to eliminate particulates, bacteria and endotoxins.
• Real-time sensors for conductivity, TOC and bacterial monitoring.

References

1. Nabulsi R., Al-Abbadi M. A. Impact of Water Quality on Laboratory Testing. Laboratory Medicine. 2014;45(4):e159–e165.
2. Ander E. L., Watts M. J., Smedley P. L. Variability in private drinking water chemistry. Environmental Geochemistry and Health. 2016;38(6):1313–1332.
3. Master S., Welter G. J., Edwards M. Seasonal variations in lead release. Environ Sci Technol. 2016;50(10):5269–5277.
4. ASTM D1193: Standard Specification for Reagent Water. ASTM International.
5. ISO 3696: Water for analytical laboratory use – specification and test methods. ISO.
6. CLSI GP40: Preparation and Testing of Reagent Water. 4th ed. CLSI. 2019.
7. Urbina M. A., Watts A. J. R., Reardon E. E. Labs should cut plastic waste too. Nature. 2015;528:479.