University laboratories rely on a constant supply of pure water for a variety of purposes, from glass washing to reagent preparation to instrumental analysis. Here, Amanda Cove, Field Sales Manager at Veolia Water Technologies UK discusses the importance of having a reliable source of purified water and what universities can do to ensure the right system is selected.
Water’s status as the universal solvent means it can be used in a wide range of applications, such as separation and extraction science. Even better, water is cheaper, less flammable and more environmentally friendly than most organic solvents – making it an essential reagent in university laboratory settings.
Without pure water, very few experiments, tests or reactions would be possible. More importantly, many biochemical reactions will only take place within pure aqueous solutions. For example, universities carrying out cutting edge research in molecular biology work with very sensitive data that can be influenced by outside sources such as impure water. In order to achieve ultra-sensitivity, pure water is essential as it provides more control over the type of substances dissolved and the exact concentration of solute, ensuring a higher experimental reproducibility. Many types of errors are due to sample contamination or poor water quality, which can greatly hinder the ability to obtain good quality data.
The initial factor that needs to be considered when selecting a pure water solution is the type or types of pure water required. Students studying and learning in laboratory settings are going to have a variety of pure water needs for different applications. Types of water are defined as follows:
- Type I water or Ultra-Pure Water has undergone a high level of purification in order to meet strict water purity requirements. This critical reagent is used in many highly sensitive scientific applicationssuch as HPLC, LC-MS, GC-MS, GFAAS, PCR and cell culture.
- Type II or Purified Water is laboratory feed water that has a resistivity level of up to 10 MΩ-cm and is used in general laboratory functions such as buffers, pH solutions and microbiological culture.
- Type III or Primary Grade Water is the lowest laboratory water grade and is used for non-critical work such as glassware rinsing, heating baths and filling autoclaves.
One of the most common ways to ensure a constant supply of pure water is by purchasing bottled pure water. This is often seen as a quick fix solution for laboratories as it is believed to be more economical but can very quickly become far more expensive as costs mount up. However, it is important to be aware of the potential complications. The purity level of the different types of water only identifies the purity of the water itself, and does not include how the water is stored, or the materials used to store it. For example, purified water is often supplied in plastic bottles, and if manufactured incorrectly, the plastic could contaminate the water with organic plasticisers, moulding release agents, solvents and monomers.
In addition, once a bottle with Ultra-Pure Water has been opened, it is estimated that the water purity level degrades from Ultra-Pure (Type I) to Primary Grade (Type III) in five minutes, because air pollutants are quickly introduced to the water, which reduces the resistivity from 18.2 MΩ-cm to 0.05 MΩ-cm. The Clinical and Laboratory Standards Institute (CLSI) highlights that bottled water should only be purchased at the rate that it is used in order to avoid the prolonged storage of an open container. With this in mind, the use of bottled water in laboratory applications can actually be a costly solution that can jeopardise the integrity of scientific results if not carefully monitored.
An alternative, more flexible option, is to purchase a point of use water system. University laboratory departments working on research can rest assured that the necessary ultrapure water will remain ultrapure, as the water is only used when it is needed, and will not be exposed to any air pollutants.
Purchasing an in-house point of use system can be a long-term, cost-effective solution. While the whole life cost of the system could be considered expensive, including the initial investment and maintenance, the actual costs of water per litre is very low. These systems also help lower the environmental impact of the university by reducing plastic waste that can occur when using water bottles as a pure water resource.
At Veolia Water Technologies’ UK (VWT UK) we offer several point of use compact water systems including our latest Purelab® Quest, a lab water purification unit that delivers Type I, II and III water. The latest system has been engineered to offer an ideal solution for small, public sector or university facilities that need a simple way of producing lab quality water without the risk, waste and complexity of managing packaged pure water.
For laboratories working with a small amount of space, Purelab® Quest is a wall mountable system that can provide all three types of pure water, saving valuable counter space. In addition, the technology has been designed to keep interruptions to a minimum when working within a tight schedule. It can deliver 1.2 litres a minute and features automatic volumetric dispensing from 100 ml to 7 litres. This allows users to initiate delivery and walk away to complete other tasks rather than wait.
As the integrity of water is of utmost importance for university teaching and research, it helps to have a system which can monitor water quality during usage. To prevent the biofilm contamination that is a risk even in ultrapure systems, PURELAB® Quest has an in-built, automatic recirculation function that prevents the water becoming static and allowing biofilms to form.
The design of the system allows easy access to change consumables, such as filters, and the pre-programmed annual sanitisation procedure is carried out with minimal user intervention and without exposure to hazardous chemicals.
For university laboratory applications, there are a number of factors that need to be considered when selecting a pure water solution, from the types of pure water required to the preferred pure water process and the design of the system itself. With so many variants it can often seem to be an overwhelming process. By engaging with a water technologies specialist as early as possible, this process can be simplified and the most effective solution ultimately selected.
To find out more about PURELAB® Quest and the rest of the range visit