- What it is. This pH 10 buffer solution is a color-coded blue pH standard used to calibrate pH meters and electrodes in the alkaline range. It is offered in 1-pint and 1-gallon sizes, so labs can match the volume to how often they calibrate.
- Why calibrate at pH 10. Most pH meters calibrate with two or three buffers. pH 7 sets the zero point, and a second buffer sets the electrode slope. When samples are alkaline, pairing pH 7 with pH 10 brackets the measurement range, so readings between 7 and 10 are interpolated rather than extrapolated, which improves accuracy.
- How a buffer holds its pH. A buffer contains a weak acid and its conjugate base, or a weak base and its conjugate acid, in balanced amounts. When small amounts of acid or base enter the solution, one partner neutralizes them, so the pH barely moves. That resistance to change is what makes a buffer a reliable reference point for calibration, unlike plain water.
- Why color-coded blue. Blue is the widely used color for pH 10 buffers, alongside red for pH 4 and yellow for pH 7. Color coding lets technicians identify the right buffer at a glance, reduces mix-ups during multi-point calibration, and makes it easier to spot a buffer poured into the wrong container.
- Sensitive to carbon dioxide. Alkaline buffers absorb carbon dioxide from the air, which forms carbonic acid and gradually lowers the pH. That is why manufacturers recommend using an opened pH 10 buffer sooner than pH 4 or pH 7. Keep the container closed, pour out only what you need, and discard used buffer rather than returning it to stock.
- Temperature matters. A buffer's pH changes slightly with temperature, so the value printed on the label applies at 25 °C. For best accuracy, calibrate at the same temperature as your samples, use a meter with automatic temperature compensation, and apply the temperature-correction values supplied with the buffer when they are provided.
- Two sizes for different workloads. The 1 pint size (ZB1634-16EA) suits benches that calibrate a few times a week, and its smaller volume is used up before carbon dioxide uptake becomes a concern. The 1 gallon size (ZB1634-128) suits QC and production labs that calibrate several meters daily.
- Calibration best practice. Rinse the electrode with deionized water, blot it gently between buffers, immerse it in a fresh buffer in a clean beaker, stir gently, and wait for a stable reading before accepting each point. Calibrate before each day's measurements, or more often as the method requires, and record the meter-reported slope to track electrode health.
- Where it is used. Use pH 10 buffer to calibrate benchtop, portable, and in-line pH meters in water and wastewater treatment, environmental testing, food and beverage QC, chemical manufacturing, education, and any process where samples run alkaline. It pairs with Lab Pro's Buffer Solution pH 7, Yellow, and Buffer Solution pH 4, Red for full three-point calibration.
Technical Specifications
| Product | pH 10 buffer solution, color-coded blue |
| Nominal pH | 10 at 25 °C |
| Color Code | Blue |
| Use | pH meter and electrode calibration, slope verification |
| Package Sizes | 1 pint; 1 gallon |
Available Variants
- ZB1634-16EA (BB2070-500): 1 pint, sold individually, for occasional calibration.
- ZB1634-128: 1 gallon for labs that calibrate several meters daily.
Applications / Common Uses
- pH meter calibration: Serves as the alkaline calibration point alongside pH 7.
- Slope verification: Checks electrode response after calibration or cleaning.
- Daily QC checks: Confirms meter accuracy before a run of alkaline samples.
- Water and wastewater testing: Brackets alkaline samples in treatment and compliance testing.
- Teaching labs: Demonstrates buffer behavior and meter calibration.
Storage, Handling & Shipping
Store pH 10 buffer tightly closed at room temperature, protected from light and freezing. Because alkaline buffers absorb carbon dioxide from the air, limit the time the container stays open and use opened stock within the period stated on the label or certificate.
- Storage temperature: Store at room temperature and protect from light and freezing.
- Contamination control: Pour the amount needed into a clean beaker; never return used buffer to stock or dip an electrode into the stock container.
- Shelf life: Use before the expiration date on the label; once opened, use within the period stated on the certificate or label.
- Rinsing: Rinse electrodes with deionized water between buffers to prevent carryover.
Related Categories & Services
- Shop pH Buffers for related products in this category.
- Explore Buffers by Lab Pro and Buffers, Standards & Solutions.
- Vendor Managed Inventory (VMI) Program: Lab Pro can stock, track, and replenish this item on site so it never runs out. Contact info@labproinc.com or 888-452-2776 to set up a VMI assessment.
