Laboratory water A key reagent for experimental success

Význam tématu

Water serves as a fundamental reagent across laboratory workflows, yet common sources—tap and bottled water—contain a range of contaminants (particles, ions, organic compounds, microorganisms and dissolved gases) whose variability can jeopardize assay accuracy, reproducibility and instrument integrity.

Cíle a přehled studie

This white paper aims to clarify laboratory water purity requirements, present international and proprietary classification systems (ASTM, ISO, CLSI and ELGA), and guide selection between in-house purification systems and bottled water to achieve reliable, cost-effective and sustainable water supplies.

Použitá metodika a instrumentace

Key purification technologies and their roles:

• Reverse osmosis (RO) for broad-spectrum removal of colloids, organics and dissolved ions
• Ion exchange (IX) and electrodeionization (EDI) for high-resistivity water by exchanging or electrochemically removing ions
• Microfiltration/ultrafiltration to eliminate microorganisms, endotoxins and fine particulates
• Ultraviolet (UV) oxidation for organic degradation and microbial inactivation
• Distillation and degassing for volatile impurities and gas removal

Water quality is routinely assessed by resistivity, total organic carbon (TOC), bacterial count and endotoxin levels, defining grades from Type III (general laboratory use) up to Type I+ (ultrapure analytical grade).

Hlavní výsledky a diskuse

Impact of water purity on analytical and biological techniques:

• High-performance liquid chromatography (HPLC) and ion chromatography (IC) demand low ionic and organic backgrounds to maintain baseline stability and resolution.
• Inductively coupled plasma mass spectrometry (ICP-MS) requires ultrapure water with resistivity >18.2 MΩ·cm and TOC <5 ppb to avoid false positives at ppt levels.
• Polymerase chain reaction (PCR) necessitates nuclease-free water devoid of inhibitory cations and organic contaminants.
• Blotting and immunohistochemistry protocols can be compromised by bacterial enzymes, unwanted proteins, metal ion precipitates and pH shifts.

Přínosy a praktické využití metody

Employing the correct water grade ensures consistency and accuracy, reduces experimental failures and instrument maintenance, and supports regulatory compliance. In-house purification systems offer long-term cost savings, ample throughput, reduced plastic waste and a lower carbon footprint compared to bottled alternatives.

Budoucí trendy a možnosti využití

Future developments include integrated real-time TOC and resistivity sensors, modular platforms enabling dynamic grade selection, energy-efficient membrane and UV technologies, and digital connectivity for remote monitoring and data logging within laboratory information management systems.

Závěr

Optimizing laboratory water through standardized classification and tailored purification enhances experimental reliability, operational efficiency and environmental sustainability. Collaboration with water-treatment specialists ensures appropriate system design, seamless installation and ongoing support.

Reference

• Nabulsi R. and Al-Abbadi M.A. Review of the Impact of Water Quality on Reliable Laboratory Testing and Correlation with Purification Techniques. Laboratory Medicine. 2014;45(4):e159–e165.
• ASTM D1193-06. Standard Specification for Reagent Water.
• ISO 3696:1987. Water for analytical laboratory use – specification and test methods.
• CLSI GP40: Preparation and Testing of Reagent Water in the Clinical Laboratory, 4th Edition.