| An on demand supply of purified water is essential for pharmaceutical laboratories to operate effectively, explains Mark Bosley of Purite
Purified water is used for a wide range of applications in pharmaceutical laboratories, from drug formulations to glassware rinsing. In order for these to be carried out effectively and safely, the water used needs to be suitably processed and treated to eliminate microbial, chemical and endotoxin contaminants. The latest generation of water purification technology is now making this achievable more simply and cost-effectively than was previously possible.
A range of solutions is now available to produce varying levels of water purity for different applications, with the highest levels typically being required in cell culture, media preparation, DNA sequencing and genome research. It is worth noting that water purity for these applications is normally measured in terms of either resistance (expressed as Megohms centimetre or MΩcm) or conductivity (measured in microSiemens per centimetre or μS/cm), as the concentration of ionic contaminants will determine the level of electrical conductivity.
MEASURING QUALITY
In the pharmaceutical industry, water quality is regulated by various national and international bodies, specifying three commonly used grades of water. The United States Pharmacopoeia (USP) specify two grades – purified water (PW) and water for injection (WFI), whereas the European Pharmacopoeia (EP) specify an additional grade – highly purified water (HPW).
These pharmacopoeia outline specific parameters and measuring criteria for the water used for certain applications; however, they do not typically detail the system design considerations or maintenance regimes necessary to achieve these quality levels. This falls within the remit of a number of validating bodies, such as the US Food and Drug Administration (FDA), which aim to ensure compliance with standards by checking that system design, installation, monitoring and maintenance procedures are in place to facilitate consistent and traceable performance to the relevant standards. In addition to these organisations, a number of documents are available, such as the current good manufacturing practice (cGMP) and the ISPE Water and Steam Guide, which also provides assistance for organisations with purified water requirements. |
