Lab workers tend to treat water systems like utility or house water—open the spout and pour it out. That is partly true, as water systems have become ultra reliable. What scientists often fail to note is how thoroughly lab operations depend on water quality. There may be some leeway in certain operations, such as cleaning glassware that will wind up in an autoclave, but even there delicate techniques such as atomic absorption and polymerase chain reaction are extremely sensitive to impurities.
Many labs, including college facilities, still use double or triple distillation as their pure water system. Mark Lockwood, president of LabStrong (Dubuque, IA) takes issue with the notion that distillation is a “dinosaur” that refuses to accept extinction.
Lockwood notes that distillation remains the simplest, most reliable, and consistent water source. Water picks up carbon dioxide within the condenser, so the product in the beaker or flask is the same as what exits the distillation unit. “If you take a type 1 system and draw water off it, the meter may say 18.2 megohm. But within seconds of standing in a beaker it will drop to 10 megohm because it is drawing in carbon dioxide.”
Distillation has several other benefits. Stills may be shut down during long breaks or facility closedowns and be up and running minutes after they are turned on. “You don’t need to find or purchase consumables to restart a distillation system.”
Distillation generally produces type 2 water, which can serve most lab functions as well as provide feedstock for type 1 deionization systems.
In addition, distillation removes microorganisms, toxins, and all nonvolatile contaminants without requiring expensive filtration or adsorbents; the process that produces the water also purifies it. Finally, distillation requires no consumables. “If it’s boiling, you’ll get the performance you need,” Lockwood adds.
More from less
Working under tight budget constraints, today’s laboratories strive to get the most out of precious resources. Economizing extends to every aspect of running labs, including “utilities” such as pure water systems. “Labs are much more conscious not only of capital costs but of ongoing or operating costs,” observes Julie Akarna, PhD, product manager for lab water at Thermo Fisher Scientific (Asheville, NC). “They do not want to replace water systems.”
Akarna notices an increase in users interested in generating type 1 water from tap water. In the past this involved purchasing multiple systems for pretreatment, water storage, and polishing. “These days they want one system that does everything,” Akarna says. This allows them to maintain one set of cartridges, for example, and saves both space and maintenance. Akarna describes space as a factor that lab designers often overlook. At one time most lab water systems were quite large; today they tend to be more compact.
A variation on this involves maintaining one type 2 water system for both general lab water use and to feed a type 1 system. Here, an appropriate storage container feeds the type 1 system and serves as a reservoir for glassware rinsing, media and buffer constitution, instrumentation, and other noncritical applications.
Related to space savings is the growing trend toward remote location of water systems, often completely out of sight in a passageway or utility area. That configuration not only saves space but also allows several rooms to share pure water systems. Thermo’s take on this is “remote dispensing,” which also distributes water volumetrically.
Labs are especially cognizant of maintenance and repairs, often eschewing service contracts for instruments or systems for which outside service is now considered a luxury.
Luckily, most water systems today are easy to maintain by laboratory personnel. “They’re relatively simple systems,” Akarna says. Most maintenance consists of changing cartridges, filters, and ultraviolet lamps on schedule. Vendors have specifically designed water systems for low maintenance, with consumables as plug-and-play components. Thermo has rewritten its product literature to reflect the evolution toward simplicity.
Other than consumables, users need to remember to perform only what Akarna calls a “spring cleaning”—actually a periodic system purge and rinse. Some water systems feature a sanitization cycle that Akarna advises users to run each time they change the deionization cartridge. The process involves adding a cleaning solution and employing a dummy cartridge where the deionizer is usually installed. For certain Thermo devices, the user selects a “Clean System” command from the menu. The process takes about 20 minutes.
Here come the regs
One does not normally connect water systems with the regulation of electronic records, but that time has arrived.
During the early 2000s the U.S. Food and Drug Administration promulgated 21 CFR Part 11, a regulation that seeks to ensure the security and trustworthiness of electronic records in the pharmaceutical and biotechnology industries. Since then, vendors have sought to make their instrument and manufacturing systems compliant with this regulation.
According to Jean Mahooti, global product manager for Lab Solutions–Labwater at Merck Millipore (Guyancourt, France), the prominence of lab water in ensuring quality, particularly during preclinical “GLP” exercises, demands the rigor of a fully robust recordkeeping system.
“Pure lab water is used extensively during pharmaceutical development and for both quality assurance and quality control,” Mahooti says. Labs must demonstrate control over water quality and be able to trace its origins and possible contaminants. “They spend a lot of time checking each water system, then acquiring and recording records on paper. All this takes time.”
Problems also arise when companies run the same assay using water of ostensibly the same quality but originating in two different parts of the world. Standardization and harmonization across labs and continents are possible only with CFR-compliant systems.
CFR Part 11 applies in both manufacturing and development. Labs operating with paper records need not comply. “But as soon as they go to electronic records they must and in some cases [must] store the data for up to forty years.” A CFRcompliant system all but guarantees that waterrelated records will not be tampered with.
Article Courtesy of Lab Manager Magazine: Laboratory Water: Defining Consistency for Lab Operations
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