Purified Water
Buy Deionized, HPLC, USP and LC/MS Grade Water in Sizes From 4 Liters to 275 Gallons.
Buy purified water online in the grade your process needs, with the price right on the page. Deionized Water, Lab Grade, Kosher is the workhorse for general laboratory rinsing, reagent preparation and equipment cleaning and scales up to 275 gallon totes. USP Grade Water meets pharmacopeia standards for pharmaceutical and personal care formulation use. HPLC Grade Water and LC/MS Grade Water are tested to the purity levels that chromatography work demands. And Deionized Water Vented Wash Bottles, filled and sealed in convenient LDPE bottles, cover everyday bench use without pulling from a bulk container.
Every purified water product ships with its SDS and COA posted online. The deionized Lab Grade product is Kosher certified, confirmed from the live product title. Purified water ships to business, lab and school addresses rather than residential ones, and Autoship is available on four of the five products here, making recurring orders straightforward for labs that go through large volumes regularly.
256,000+
customers served
99.5%
of orders ship in 1–2 business days
98.9%
inventory accuracy
SDS + COA
available online, every product
Purified Distilled Water Suitable For Many Applications
Purified Water - 1 products All Filters
Purified Water - 1 products About Purified Water
H2O without the extras. Tap water, depending on the source, carries dissolved minerals, chlorine, chloramines, bacteria, particulates and trace organics, all of which can interfere with analytical results, degrade equipment or introduce variability into formulations. Purification removes those contaminants, though the method used matters, because different purification processes achieve different results and leave the water suitable for different tasks. Deionization removes dissolved ions by passing water through ion exchange resins, producing water with very low conductivity but not necessarily removing dissolved organics or microorganisms. Distillation removes most contaminants by boiling and condensing, but also not all organics. HPLC and LC/MS grade water goes through additional processing steps to remove the trace organics that would show up as background noise in a chromatography system. USP grade meets specific pharmacopeia tests for use in pharmaceutical applications. The right water for the job depends on what it's going into, not just on what grade sounds most impressive.
COMMON APPLICATIONS
General laboratory reagent preparation, buffer making and equipment rinsing, where deionized Lab Grade water is the standard choice and the one labs go through in volume. HPLC and LC/MS mobile phase preparation, where trace organic contamination in the water would directly affect the chromatogram. USP Grade water in pharmaceutical, personal care and cosmetic formulations that specify pharmacopeia grade material. Bench rinsing and glassware washing throughout the lab, where the ready filled LDPE wash bottles are practical. Industrial process water in manufacturing, cooling and cleaning applications where ion content needs to be controlled.
GRADES EXPLAINED
Lab Grade Deionized Water (Kosher certified) is the volume choice for general lab use: rinsing, reagent prep and routine procedures where the highest analytical standard isn't required. USP Grade meets the United States Pharmacopeia standards for purified water, the one to buy when a formulation specifically calls for USP water. HPLC Grade meets the purity requirements for high performance liquid chromatography mobile phase use. LC/MS Grade goes further still, tested for the very low background organics that mass spectrometry demands; using ordinary lab water as LC/MS mobile phase would introduce background contamination that shows up in the spectrum.
TYPES & GRADES AT A GLANCE
Volume choice for general lab use; scales to 275 gallon totes. Kosher certified.
Pharmacopeia standard for pharmaceutical and personal care formulation.
For chromatography mobile phase preparation.
For LC/MS mobile phase, tested to lowest organic background levels.
Ready filled for bench rinsing and glassware washing.
WHY BUY FROM LAB ALLEY
256,000+ customers already order their chemicals and reagents from Lab Alley. 99.5% of orders ship within 1 to 2 business days, and 98.9% inventory accuracy means the grade you see in stock is the grade that ships. SDS and COA are available online for every purified water product, and our Deionized Water, Lab Grade carries Kosher certification. Autoship is available on four of the five products in this category for recurring lab orders.
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Frequently Asked Questions
Where can I buy deionized or purified water online?
Right here. We carry deionized water in Lab Grade up to 275 gallon totes, plus USP, HPLC and LC/MS grade water for more demanding applications. Pick the grade and size, check the price, and order without needing a quote for standard sizes. Most in stock orders ship within 1 to 2 business days, and Autoship is available on four of the five products here for labs that order regularly.
What is the difference between deionized water and distilled water?
The process. Distillation boils the water and condenses the steam, leaving behind dissolved minerals, most bacteria and many heavy metals. Deionization passes the water through ion exchange resins that specifically remove dissolved ions, producing water with very low electrical conductivity. Both remove common contaminants, but neither removes all possible impurities alone. HPLC and LC/MS grade water goes through additional processing, specifically to remove the dissolved organics that neither simple distillation nor deionization eliminates but that would affect sensitive analytical work.
Which grade should I buy?
Match it to the application. Rinsing glassware, making buffers and preparing everyday reagents: Lab Grade Deionized Water, the volume choice. Pharmaceutical or personal care formulation that calls for pharmacopeia grade: USP Grade. Preparing HPLC mobile phase: HPLC Grade. Running LC/MS: LC/MS Grade, which is tested to the lower organic background levels that mass spectrometry requires. If in doubt between HPLC and LC/MS, LC/MS is the more stringent spec and covers the HPLC requirement too.
Is your deionized water Kosher certified?
Yes, the Deionized Water, Lab Grade product carries Kosher certification, confirmed in its live product title. The USP, HPLC and LC/MS grade water products carry no religious certification, so if certification matters for your application, the Lab Grade deionized water is the right choice here.
Can I buy purified water in bulk?
Yes. The Deionized Water, Lab Grade product scales all the way up to 275 gallon totes, with 55 gallon drums available too, right on the product page. For volumes beyond the listed sizes or a recurring scheduled delivery, use Bulk & Custom Chemicals to request a quote. Autoship takes 10% off eligible repeat orders and is available on four of the five products in this category.
Can purified water ship to a home address?
No, it ships to business, lab and school addresses rather than residential ones, like the rest of our catalog. Each product page lists its specific shipping details, and Customer Care at 512-668-9918 can confirm before you order if you're unsure your address qualifies.
Why would a lab buy water instead of making its own?
Convenience and consistency. Running a deionizer in house takes equipment, maintenance and regular testing. Buying certified water means a COA with every lot and a consistent, tested spec without managing the production process yourself. The wash bottle format is practical for low volume bench use. For demanding applications like LC/MS, the trace organic testing behind certified grade water is also difficult to replicate in house without significant equipment investment.
How should purified water be stored?
In its original sealed container in a clean, dry place. Purified water readily absorbs carbon dioxide from the air, which lowers the pH and can affect sensitive applications. It also picks up trace contamination from dust and open air. Keep containers sealed when not in use, avoid storing in general areas where airborne particulates can get in, and use it promptly after opening for high grade analytical work.
Guides & Resources
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