Lab Water refers to purified water which is used in laboratory experiments. It is the most common reagent used in the laboratory.
Why Water is Important in Lab?
Laboratory performances require delivering accurate and reliable results and meet regulatory requirements while under time pressure. Many tests and procedures significantly depend upon the quality of the lab water being capable of providing consistent and reproducible results.
“Technical standards on water quality have been established by a number of professional organizations, including the American Chemical Society (ACS), ASTM International, the U.S. The ASTM, NCCLS, and ISO 3696 or the International Organization for Standardization classify purified water into Grade 1–3 or Types I–IV depending on the level of purity.”
These standards establishes the context that it is important to ensure the quality of water used in laboratory experiments as it constitutes the predominant component of a reagent. Minimum traces of salts or contaminants can result in unfortunate consequences when culturing cells or performing sensitive analytical measurements of bio-samples. Lab water systems can potentially affect the overall performance in terms of water quality, ease of use, autonomy and convenience.
Different Types of Water and its Application
There are three main types of lab water according to ASTM Standards for Laboratory Reagent Water (ASTM D1193-91). They have been classified by different attributes of the water: Resistivity, Total Organic Carbon(TOC), Bacteria and Endotoxins.
Resistivity: Resistivity measures water’s ability to resist or conduct an electrical charge. As the level of salts and minerals increases in water, the reisitivity decreases, therefore, it is easily and inexpensively monitored in a laboratory. However, please keep in mind that the resistivity of lab water is only a measurement of ionic impurities in the water and does not account for biological contaminants.
Total Organic Carbon (TOC): TOC measures the amount of organic carbon that is found in lab water. The contaminants include biological material, bacterial growth and the chemical activity of living organisms. TOC is typically measured in parts per billion (ppb), for Ultrapure Type I water systems provide TOC less than 10 ppb.
Bacteria: Bacteria are a common source of water contamination and often used to measure the quality of lab water. The number of bacterial cells in the water is counted and reported as the potential to multiple and grow in colony forming units (CFUs) per unit volume(ml). For Type I water systems, bacteria in ultra pure water must be less than 10CFUs bacterial colonies per 1ml of water.
Endotoxins: Endotoxin is a component of the exterior cell wall of Gram-negative bacteria called lipopolysaccharide (LPS) from the horseshoe crab. These toxics in lab water can negatively affect the measurement of water purity. Type 1 water quality systems typically have measurements of less than 0.03 Endotoxin Units per 1ml of water.
Three Types of Laboratory Water
Primary Grade Lab Water：ASTM Type III Pure Water
Type III grade lab water, also refer to as RO water, is water produced uses carbon filtration and the reverse osmosis (RO) purification technology. It is the most cost-effective way to reduce water contaminants and it is typically the starting point for basic lab applications, including feeding glassware washing machines and autoclaves to clean glassware, heating baths or media preparation. It can also be used as a feed water for Type I water production.
Pure Grade Lab Water：ASTM Type II Pure Water
Also known as general laboratory grade water, Type II water is produced through a combination of filtration system, which has a resistivity of 1-15MΩ-cm, making it suitable for general applications such as buffer and media production, general lab/clinical practices and general spectrophotometry. It is also used as a feed water for Type I water production.
Ultrapure Water：ASTM Type I Ultrapure Water
With a resistivity of 18.2 MΩ-cm at 25°C, Type I Ultrpure water is a requirement for highly sensitive analytical laboratories, such as:
- Cell and Tissue Cultures
- High Performance Liquid Chromatography (HPLC), Gas Chromatography(GC)
- Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
- Polymerase Chain Reaction (PCR)
- In Vitro Fertilisation (IVF)
And other highly sensitive analysis.
Underestimating the lab water needs can cost downtime and lose of experiments to the laboratory, knowing the type of water your lab needs, the top flow rate and the peak laboratory demands will help you when selecting the correct water purification system for your lab.
Learn more about water purification systems offered at unicornlifescience.com or contact us today to get the right water purification system you need!
