Product Description
LIGHT LABS is proud to offer Mediatech HEPES Buffer, 1M Liquid Solution (Cat # 25-060-CI) — a premium, sterile-filtered, highly concentrated 1M HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulphonic acid) solution for supplementing cell culture media, biochemical buffers, and biological assay systems requiring superior, CO₂-independent pH stability in the physiological range of pH 7.2–7.6. The 25-060-CI is the essential HEPES stock solution for researchers who want to add HEPES to standard cell culture media formulations that do not already contain it — particularly to DMEM, RPMI 1640, MEM, and other bicarbonate-buffered media that require CO₂ incubator supplementation for pH control.
HEPES is a zwitterionic biological buffer from the "Good's buffers" family, specifically developed for use in biological systems. Unlike sodium bicarbonate — whose buffering capacity is CO₂-dependent and rapidly loses effectiveness outside the CO₂ incubator — HEPES has a pKa of 7.66, placing it squarely in the physiological pH range of 7.2–7.6 where it provides substantially stronger buffering than bicarbonate at atmospheric CO₂ concentrations. This makes HEPES-supplemented media significantly more resistant to pH change during bench manipulations, high-throughput pipetting operations, microscopy, and any workflow where cells spend time outside the CO₂ incubator. Adding HEPES to standard bicarbonate-buffered media provides a dual buffering system that maintains pH stability both inside and outside the incubator — the same principle used in the pre-formulated HEPES-containing Mediatech media variants (10-041-CV RPMI; 10-016-CV IMDM; 10-092-CV DMEM/F-12; 15-018-CV DMEM; 15-041-CV RPMI).
The 1M concentration (238.3 mg/mL) of the 25-060-CI provides maximum versatility — add to any cell culture medium at the appropriate volume to achieve the desired final HEPES concentration (typically 10–25 mM, with 25 mM being the most common). Important safety note: HEPES has been documented to cause toxicity at concentrations above 100 mM and provides no nutritive value to cells — always use at recommended working concentrations of 10–25 mM. Sterile-filtered; pH 7.2–7.6; manufactured under ISO 13485 certified quality management system. Storage: 2°C to 30°C (ambient or refrigerator — no freezing required). LIGHT LABS is your trusted source for Mediatech cell culture reagents.
KEY FEATURES
- 1M HEPES liquid solution — 238.3 mg/mL; highly concentrated stock for flexible dilution to any working concentration
- pKa 7.66 — provides substantially stronger buffering than bicarbonate in the physiological pH range of 7.2–7.6; superior CO₂-independent pH stability
- CO₂-independent buffering — maintains physiological pH during bench manipulations, high-throughput pipetting, microscopy, and extended incubator-free procedures without CO₂ dependency
- Dual buffering advantage — add to standard bicarbonate-buffered media (DMEM, RPMI, MEM) to create a dual bicarbonate + HEPES buffer system for pH stability both inside and outside the incubator
- Recommended working concentration: 10–25 mM — add 1 mL per 100 mL of media for 10 mM; 2.5 mL per 100 mL for 25 mM HEPES working concentration
- Important: toxicity at >100 mM — always use at recommended concentrations of 10–25 mM; provides no nutritive value to cells
- Sterile-filtered — ready for direct addition to sterile cell culture media
- Low endotoxin — manufactured under industry-leading standards
- Storage: 2°C to 30°C — ambient or refrigerator; NO freezing required
- pH: 7.2–7.6
- Complete Certificate of Analysis available for each production lot
- Manufactured under ISO 13485 certified quality management system
- 100 mL bottles; 6 bottles per case
- Fisher Scientific Catalog No. MT25060CI
SPECIFICATIONS
| Attribute | Detail |
|---|---|
| Catalog Number | 25-060-CI |
| Fisher Scientific Catalog No. | MT25060CI |
| Brand | Mediatech (Corning Life Sciences) |
| Product Name | HEPES Buffer, 1M Liquid Solution |
| Chemical Name | N-2-Hydroxyethylpiperazine-N'-2-ethanesulfonic acid (Free Acid) |
| Concentration | 1M (238.3 mg/mL) |
| pKa | 7.66 |
| pH | 7.2–7.6 |
| Buffering Range | pH 7.2–7.6 (optimal) |
| Recommended Working Concentration | 10–25 mM |
| Toxicity Threshold | >100 mM — do not exceed |
| CO₂ Dependency | None — CO₂-independent buffering |
| Format | Liquid, sterile-filtered, ready-to-use |
| Endotoxin | Low — manufactured under industry-leading standards |
| Quality System | ISO 13485 certified |
| Certificate of Analysis | Yes — lot-specific CoA available |
| Volume | 100 mL per bottle |
| Packaging | 6 bottles per case |
| Storage Temperature | 2°C to 30°C (ambient or refrigerator — no freezing) |
HEPES DILUTION GUIDE — ACHIEVING TARGET WORKING CONCENTRATIONS
| Target HEPES Concentration | Volume of 1M HEPES (25-060-CI) per 100 mL Media | Volume per 500 mL Media |
|---|---|---|
| 10 mM | 1.0 mL | 5.0 mL |
| 15 mM | 1.5 mL | 7.5 mL |
| 20 mM | 2.0 mL | 10.0 mL |
| 25 mM | 2.5 mL | 12.5 mL |
HEPES vs. BICARBONATE — BUFFERING COMPARISON
| Feature | HEPES (25-060-CI) | Sodium Bicarbonate |
|---|---|---|
| pKa | 7.66 | 6.35 (CO₂/HCO₃⁻) |
| Buffering Range | pH 6.8–8.2 (optimal 7.2–7.6) | pH 7.2–7.6 only with CO₂ |
| CO₂ Dependency | None | Requires 5–10% CO₂ |
| Outside Incubator | ✓ pH stable | ✗ pH drifts rapidly |
| Cell Nutritive Value | None | None |
| Toxicity Risk | >100 mM | None at standard conc. |
| Best Use | CO₂-independent buffering; bench manipulations | Standard CO₂ incubator culture |
APPLICATIONS
- Supplementing standard bicarbonate-buffered cell culture media (DMEM, RPMI 1640, MEM, IMDM) with HEPES for CO₂-independent pH stability
- High-throughput cell culture workflows requiring stable pH during extended bench pipetting operations
- Live cell microscopy and imaging requiring pH stability outside the CO₂ incubator
- Primary cell isolation and processing requiring stable physiological pH during bench manipulations
- Preparation of custom cell culture media formulations requiring defined HEPES concentration
- Biochemical assay buffers requiring strong physiological pH buffering in the 7.2–7.6 range
- Any cell culture or biochemical application requiring CO₂-independent pH buffering at physiological pH
ORDERING INFORMATION — MEDIATECH HEPES & CELL CULTURE SUPPLEMENTS
| Cat # | Description | Concentration | Volume | Pkg |
|---|---|---|---|---|
| 25-060-CI | HEPES Buffer, 1M Liquid Solution | 1M (238.3 mg/mL) | 100 mL | 6/case |
| 10-092-CV | DMEM/F-12 50/50 Mix, L-Glutamine, 15 mM HEPES (pre-formulated) | — | 500 mL | 6/case |
| 10-016-CV | IMDM, L-Glutamine, 25 mM HEPES (pre-formulated) | — | 500 mL | 6/case |
| 15-018-CV | DMEM, High Glucose, Sodium Pyruvate, 25 mM HEPES, No L-Glutamine | — | 500 mL | 6/case |
| 15-041-CV | RPMI 1640, 25 mM HEPES, No L-Glutamine | — | 500 mL | 6/case |
| 25-056-CI | CellStripper™ Non-Enzymatic Cell Dissociation Solution | — | 100 mL | 6/case |
| 30-002-CI | Penicillin-Streptomycin Solution, 100X | 10,000 IU/mL Pen; 10,000 µg/mL Strep | 100 mL | 6/case |
| 21-031-CV | DPBS, 1X, Without Calcium & Magnesium | — | 500 mL | 6/case |
