Understanding Lab Water: The Foundation of Precision Science

The critical role of water in the lab

As a universal solvent, water is used in nearly every laboratory reagent and application, whether for rinsing, buffer or sample dilution, or as a blank. The quality of water used in the lab — and its consistency of quality — is therefore critical for the success of the tests performed.

Properties of Water

It’s important to understand why water is such a unique molecule. Read the article Water: Properties, Polarity and Its Role as a Universal Solvent to learn about its polarity, hydrogen bonding, and how these properties make it a universal solvent essential for life and work in the laboratory.

Water Contaminants

Water impurities are generally classified into five major classes: organics, inorganic ions, bacteria and their by-products, particles and colloids, and dissolved gas. Learn the sources of these water contaminants, their impacts on various laboratory instruments and experiments, and how to effectively remove them from your water supply in the article, Overview of Water Contaminants: Types, Sources and Impacts in the Lab. 

Water Purification Techniques

There are many different water purification techniques and technologies to remove contaminants from lab water. These include distillation, reverse osmosis, ion exchange resins, ultrafilters, carbon filtration and UV oxidation. Each technology has benefits and limitations. Some can remove a large fraction of several contaminants (e.g., reverse osmosis), while others excel at removing one specific type of impurity down to very low levels (e.g. ion exchange resins). As no single technology can remove all contaminants, several purification technologies are generally combined to produce pure and ultrapure water.

Water Quality Grades

Norms define different laboratory water grades for both technical and economical reasons. The purpose of these norms is to ensure that the right water quality is used for a specific application, while limiting laboratory operating costs as Type 1 ultrapure water is more expensive to produce than Type 2 or Type 3 pure water.

Determine which water grade is best suited for your specific analysis, instrument or equipment in the article, Understanding Water Quality Grades for Laboratory Applications. Ensuring that you use the optimal water type for your application will support results reliability and accuracy, while also optimizing laboratory costs.

Monitoring of Water Quality

Ensuring the purity of water used in laboratory experiments is crucial for obtaining accurate and reliable results. Contaminants such as inorganic salts and dissolved organics can significantly impact the integrity of scientific research. The article Water Quality Monitoring describes the importance of monitoring water quality in the lab, highlighting advanced techniques for detecting ionic and organic impurities via online resistivity and TOC measurements.