Weber DB™ Sterilized Pre-filled Dilution Bottles and Tubes
Sterilized Pre-Filled Dilution Bottles:
Weber pre-filled dilution bottles are used to dilute a liquid or particulate sample for the purpose of microbial enumeration on Petri plates. Our sterile buffers are manufactured per Standard Methods for the Examination of Dairy Products and Standard Methods for the Examination of Water and Wastewater. This provides an industry standard that is readily accepted by applicable regulatory agencies.
At a Glance
What is this product?
Pre-filled, gamma-irradiated dilution bottles and tubes for serial dilutions in microbial testing. Available in two formulations: Butterfield's Buffer for food, dairy, and pharmaceutical testing, and Phosphate Buffer (with magnesium) for water and wastewater testing. Bottles come in 90 mL and 99 mL fills. Tubes come in 9 mL fills. All are manufactured right here in New Jersey in strict compliance with APHA, FDA, AOAC, USP, and EPA published methods.
Who is it for?
Lab technicians, microbiologists, and QC managers in food and beverage production, dairy processing, water and wastewater treatment, pharmaceutical manufacturing, and academic research. Also for budget managers who are tired of paying for in-house buffer prep labor or overpaying their current supplier.
What are the benefits?
2-year shelf life (longest in the industry). Clear PET bottles so you can visually inspect contents. Gamma irradiated for guaranteed sterility. Color-coded lettering for quick identification. Every lot tested for pH, sterility, toxicity, fill volume, and package integrity. Recyclable bottles with attached caps. Always in stock with 1-2-3 Day Delivery (shipping upgrades on us).
What are your next steps?
Talk to your Weber Account Manager about getting samples of your preferred formulation, or scroll down to order by the case.
Each bottle is pre-filled to either 99 or 90 mL, buffered to pH 7.2 +0.2, has an overall capacity of 150 mL and is 100% recyclable. Two formulations are available:
Butterfield’s Buffer is frequently used in the food and dairy industries (APHA, FDA, AOAC or USP methods). Contains purified water, monobasic potassium phosphate and sodium hydroxide for pH adjustment.
Phosphate Buffer is the same as Butterfield’s Buffer but also contains magnesium. This is commonly used in the water and wastewater industries (APHA or EPA methods). Contains magnesium chloride, monobasic potassium phosphate and sodium hydroxide for pH adjustment.
Applications for Butterfield and Phosphate Buffers:
- Foods & Beverages
- Water and Wastewater
- Cosmetics
- Pharmaceuticals
- Environmental Samples
Sterilized Pre-Filled 9 mL Dilution Tubes:
We also manufacture sterile pre-filled dilution Tubes available in Butterfield’s Buffer. These tubes are pre-filled to 9 mL and have an overall capacity of 13 mL. This provides an advantage in working with smaller volumes in a smaller footprint.
Features & Advantages of Dilution Bottles:
Request a Certificate of Analysis (CoA) online
This product is made in strict compliance with specifications as published in the most recent edition of APHA Standard Methods for the Examination of Dairy Products; APHA Standard Methods for the Examination of Water and Wastewater; APHA Compendium of Methods for the Microbiological Examination of Foods: FDA Bacteriological Analytical Manual; FDA Milk Laboratory Evaluation Form 2400; United States Pharmacopoeia. Each lot is thoroughly tested in house with toxicity done by an independent testing laboratory and is released only after passing all specifications for pH, sterility, toxicity, fill volume, and package integrity and markings. The CoA indicates that each lot passes all of these specifications. Specific results are given for pH and toxicity analysis.
Click here to obtain a copy of the Certificate of Analysis (CoA).
Huge freight savings and faster delivery throughout the United States
Dilution bottles ship out of our Nevada warehouse for delivery to Western states and out of our Missouri warehouse for selected Southern and Midwestern states. Customers in these areas will realize significant freight savings plus shipments will be received sooner.
Eastern states will continue to receive fast and economical service from our facility in New Jersey.
Products identified by this icon indicate only the first case — of multiple case orders — will be upgraded to UPS 3 Day Select service (where applicable). The remaining cases will ship by ground and you should receive them within 1 - 3 days of receiving your first case.
Frequently asked questions
Butterfield's Buffer basics
Q: What is Butterfield's Buffer?
A: Butterfield's Buffer (also called Butterfield's Phosphate Diluent or BPD) is a sterile buffered solution used to dilute samples before microbial testing. It contains purified water, monobasic potassium phosphate, and sodium hydroxide, adjusted to pH 7.2 ±0.2. It's the standard diluent specified by APHA, FDA, AOAC, and USP for plate count procedures in food, dairy, and pharmaceutical testing.
Q: What is the difference between Butterfield's Buffer and Phosphate Buffer?
A: Butterfield's Buffer (also called Butterfield's Phosphate Diluent or BPD) is a sterile buffered solution used to dilute samples before microbial testing. It contains purified water, monobasic potassium phosphate, and sodium hydroxide, adjusted to pH 7.2 ±0.2. It's the standard diluent specified by APHA, FDA, AOAC, and USP for plate count procedures in food, dairy, and pharmaceutical testing.
Q: Why is Butterfield's Buffer preferred over saline or distilled water for dilutions?
A: Butterfield's Buffer maintains a stable pH of 7.2, which keeps microorganisms viable during the dilution process without encouraging or inhibiting growth. Plain saline or distilled water can shift in pH, potentially killing organisms before you plate them and giving you inaccurate counts.
Q: What does the pH 7.2 ±0.2 specification mean for my results?
A: It means every bottle is buffered to a near-neutral pH that won't harm the microorganisms in your sample during the dilution step. The ±0.2 tolerance is tight enough to satisfy all published regulatory methods. Each lot is tested and verified before it ships.
Using dilution bottles and tubes
Q: When do I use the 99 mL bottles vs. the 90 mL bottles?
A: Use 99 mL bottles when your method calls for a 1:100 dilution (add 1 mL of sample to 99 mL of diluent). Use 90 mL bottles when your method calls for a 1:10 dilution of a larger sample (add 10 mL or 10 g of sample to 90 mL of diluent). Your specific method will specify which dilution ratio to use.
Q: When should I use the 9 mL dilution tubes instead of bottles?
A: The 9 mL tubes are for serial 1:10 dilutions when you're working with smaller volumes (1 mL transfers). They take up less bench and incubator space than bottles. Most food and dairy labs use a combination: bottles for the initial dilution and tubes for subsequent serial dilutions in the series.
Q: Can I use these dilution bottles directly for plating?
A: Yes. After adding your sample and mixing, pipette the desired volume directly from the bottle onto your plates or into your pour plate media. The 150 mL total capacity gives you enough headroom to add a sample and still have room to mix without spilling.
Q: How do I mix my sample once it's in the bottle?
A: Cap the bottle and shake it 25 times in a 30 cm (1-foot) arc within 7 seconds. This is the standard mixing procedure described in most APHA and FDA methods. The attached cap makes this step simple and prevents cross-contamination from loose caps.
Q: What is the total capacity of each bottle and tube?
A: Dilution bottles have a 150 mL total capacity (filled to 90 mL or 99 mL). Tubes have a 13 mL total capacity (filled to 9 mL). The extra headspace is there so you can add your sample, cap it, and mix without overflow.
Formulation and compliance
Q: Which regulatory methods do these dilution bottles comply with?
A: They are manufactured in strict compliance with the most recent editions of:
APHA Standard Methods for the Examination of Dairy Products
APHA Standard Methods for the Examination of Water and Wastewater
APHA Compendium of Methods for the Microbiological Examination of Foods
FDA Bacteriological Analytical Manual (BAM)
FDA Milk Laboratory Evaluation Form 2400
United States Pharmacopoeia (USP)
Q: What quality control testing does each lot go through?
A: Every lot is tested in-house for pH, sterility, fill volume, and package integrity. Toxicity testing is performed by an independent laboratory. A lot is released only after it passes all specifications. Documentation is available upon request.
Q: Are Certificates of Analysis available?
A: Yes. Contact our customer service at 800-328-8378 or email info@weberscientific.com to request a Certificate of Analysis for any lot number.
Q: What is the exact composition of each formulation?
A: Butterfield's Buffer contains purified water, monobasic potassium phosphate (KH₂PO₄), and sodium hydroxide (NaOH) for pH adjustment. Phosphate Buffer contains the same ingredients plus magnesium chloride (MgCl₂), which is required for water and wastewater methods.
Storage and shelf life
Q: What is the shelf life of these dilution bottles?
A: 2 years from the date of manufacture. That's the longest shelf life in the industry for pre-filled dilution bottles.
Q: How should I store them?
A: Store at room temperature, out of direct sunlight. No refrigeration required. Keep them in their original packaging until you're ready to use them.
Q: How do I know when my bottles expire?
A: The expiration date is printed on each case and on individual bottles.
Q: Can I use a bottle after the expiration date?
A: No. After the expiration date, sterility and pH stability are no longer guaranteed. Using expired diluent can introduce variability into your results or compromise sterility.
Bottles and packaging
Q: What are the bottles made of?
A: Clear PET (polyethylene terephthalate). Weber DB bottles are the only PET disposable dilution bottles on the market. The material gives you glass-like clarity so you can visually inspect the contents, but unlike glass, they won't shatter if dropped.
Q: Are the bottles recyclable?
A: Yes. The PET bottles are 100% recyclable. The attached polyethylene caps are also recyclable in most municipal programs.
Q: How many bottles or tubes come in a case?
A: Dilution bottles ship in cases of 72. Contact us for tube case quantities and any bulk pricing.
Q: Why are they called "dilution bottles" and not "buffer bottles"?
A: In microbiology, the term "dilution bottle" (or "dilution blank") has been standard terminology for decades. It describes the bottle's function: holding a pre-measured volume of sterile diluent that's ready for serial dilutions. The name tells technicians exactly what the product is for.
Food and dairy testing
Q: Which formulation do I use for food safety testing?
A: Butterfield's Buffer. It's the diluent specified by the FDA Bacteriological Analytical Manual (BAM) and APHA Compendium of Methods for the Microbiological Examination of Foods for standard plate counts and pathogen testing in food products.
Q: Can I use these for USDA poultry testing?
A: Yes. Weber also manufactures the Mega-Reg 400, a 400 mL container of sterile Butterfield's Phosphate Diluent designed specifically for whole chicken carcass rinse testing for generic E. coli, as required by USDA-FSIS regulations.
Q: Are these acceptable for dairy testing under APHA Standard Methods?
A: Yes. The Butterfield's Buffer formulation is manufactured per the specifications in APHA Standard Methods for the Examination of Dairy Products and is compliant with FDA Milk Laboratory Evaluation Form 2400.
Q: Can I use Butterfield's Buffer for HACCP verification testing?
A: Yes. Butterfield's Buffer is the standard diluent for plate count methods used in HACCP verification programs for food and dairy products.
Water and wastewater testing
Q: Which formulation do I use for drinking water testing?
A: Phosphate Buffer (the formulation with magnesium chloride). It's specified by APHA Standard Methods for the Examination of Water and Wastewater and EPA methods for microbial testing of drinking water and wastewater.
Q: Why does water testing require the magnesium chloride?
A: EPA and APHA water testing methods specify the addition of magnesium chloride to the phosphate buffer. Magnesium supports the viability of stressed organisms commonly found in water samples, particularly those that have been through chlorine treatment or other disinfection processes.
Q: Can I use Phosphate Buffer for environmental water samples?
A: Yes. The Phosphate Buffer formulation is suitable for testing surface water, groundwater, recreational water, and wastewater per APHA and EPA methods.
Pharmaceutical and academic use
Q: Are these dilution bottles acceptable for USP microbial testing?
A: Yes. The Butterfield's Buffer formulation is manufactured per United States Pharmacopoeia specifications and is suitable for USP microbial limits testing and sterility testing dilutions.
Q: Can academic labs use these for teaching?
A: Yes. Pre-filled dilution bottles eliminate the prep time of making buffer from scratch, which frees up class time for actual instruction. They also remove buffer preparation as a source of variability in student results, so instructors can focus on teaching technique rather than troubleshooting bad media.
Switching from in-house prep to pre-filled bottles
Q: Why should I switch from making my own Butterfield's Buffer?
A: Three reasons. First, consistency: every bottle is manufactured under controlled conditions with rigorous QC, so your diluent is never a source of variability in your data. Second, time: you stop spending labor hours weighing chemicals, dissolving, adjusting pH, sterilizing, and filling bottles. Third, cost: when you factor in chemical costs, labor, autoclave time, and QC testing of your in-house buffer, pre-filled bottles are often cheaper.
Q: I've been making my own buffer for years. How do I validate the switch?
A: Request a free sample case from us. Run your standard methods side by side with your in-house buffer and the pre-filled bottles. Compare your plate counts. Most labs see equivalent or better results with pre-filled bottles because the manufacturing QC is tighter than what most individual labs can achieve in-house.
Q: What if my auditor asks about the switch?
A: We provide lot-specific documentation including Certificates of Analysis. The product is manufactured per published APHA, FDA, AOAC, USP, and EPA specifications. Auditors generally prefer a documented, validated commercial product over in-house preparations that depend on individual technician skill.
Ordering and delivery
Q: Can I get free samples before committing to a full order?
A: Contact your Weber Account Manager to request a sample of your preferred formulation and size, or go ahead and place your first order. Our 100% Satisfaction Guarantee means you can return for a full refund for any reason within 30 days of purchase if they don't work for you for any reason.
Q: How fast will my order arrive?
A: Our 1-2-3 Day Delivery program gets your order to you within one to three business days. If a shipping upgrade is needed to meet that promise, we cover the cost, not you. Orders placed by 3:30 PM EST ship the same day.
Q: Do you ship from multiple locations?
A: Yes. Dilution bottles ship from our New Jersey headquarters, our Nevada warehouse (for Western states), and our Missouri warehouse (for selected Southern and Midwestern states). This means faster delivery and lower freight costs regardless of where you are in the continental US.
Q: Can I set up a standing order?
A: Yes. Standing orders guarantee priority shipping, can qualify you for volume pricing even when receiving smaller shipments, and eliminate the administrative burden of reordering. Contact us at 800-328-8378 to set one up.
Q: Is there volume pricing available?
A: Yes. Contact us directly for volume pricing on larger or recurring orders.
About Weber Scientific
Q: Who manufactures these dilution bottles?
A: We manufacture them right in our facility in New Jersey. We've been making dilution bottles since we opened our doors in 1959.
Q: Is Weber Scientific a major supplier of dilution bottles?
A: We are one of the largest provider of pre-filled dilution bottles and Butterfield's Buffer to the food and beverage industry. Our products are distributed and trusted by laboratories around the world.
Q: What if I'm not satisfied with my order?
A: We offer a 100% satisfaction guarantee and a 30-day return policy. If you're not satisfied, call 800-328-8378 for a replacement or return authorization.
Q: How do I contact Weber Scientific?
A: Call us at 800-328-8378, or email us at info@weberscientific.com. Our customer service team is available Monday through Friday, 8 AM to 5 PM EST.
| Item No. | Alt. Part No. | Brand Name | Product Description | Formulation | Fill | Unit of Measure | Your Cost | Purchase | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Weber DB™ Sterilized Pre-filled Dilution Bottles
3127-14
|
EF40700 | Weber Scientific | Pre-filled Dilution Bottles | Butterfield's Buffer | 99 mL | Case of 72 |
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Weber DB™ Sterilized Pre-filled Dilution Bottles
3127-44
|
EF40701 | Weber Scientific | Pre-filled Dilution Bottles | Butterfield's Buffer | 90 mL | Case of 72 |
|
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|
Weber DB™ Sterilized Pre-filled Dilution Bottles
3127-29
|
EF40702 | Weber Scientific | Pre-filled Dilution Bottles | Phosphate Buffer | 99 mL | Case of 72 |
|
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|
Weber DB™ Sterilized Pre-filled Dilution Bottles
3127-59
|
EF40703 | Weber Scientific | Pre-filled Dilution Bottles | Phosphate Buffer | 90 mL | Case of 72 |
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Pre-filled 9 mL Dilution Tubes
3127-09
|
EF40704 | Edge Biologicals | Pre-filled 9 mL Dilution Tubes | Butterfield's Buffer | 9 mL | Case of 100 |
$74.91
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