Tris-Based Buffers - Category Selection Guide
Eight product lines, one page. Pick the line your protocol needs and go straight to its product page — the chemistry, the temperature caveat, and the application guidance follow below.
| Tris-Based Buffers | Core Basis | Primary Use | Product Page |
|---|---|---|---|
| TBS, 20X (Tris Buffered Saline), Non-Sterile | Concentrated Tris-HCl + NaCl | Concentrated stock for long shelf-life | Viewarrow_forward |
| Tris Based Transfer Buffers | Tris-Glycine electroblotting matrix | Protein membrane transfer | Viewarrow_forward |
| Tris Based Running Buffers | Conductive Tris ion matrix | Protein electrophoresis | Viewarrow_forward |
| Tris Based Lysis/Extraction Buffers | Tris-HCl + surfactants | Total protein extraction | Viewarrow_forward |
| Tris Based Washing Buffers | Tris-saline + mild detergent | Background rinsing | Viewarrow_forward |
| Tris Based Blocking Buffers | Tris-saline + passivating proteins | Phosphoprotein assays | Viewarrow_forward |
| Tris-based Buffers | Purified Tris core | Versatile benchtop dilutions | Viewarrow_forward |
| TE Buffer | Tris-HCl + EDTA | Long-term DNA/RNA storage | Viewarrow_forward |
Not sure which line? Compare the Tris buffering parameters · See applications by workflow · Read the FAQ
The numbers behind the workhorse buffer
Precise pH control is non-negotiable in molecular biology, biochemistry, and cell biology. Tris-based buffers built around Tris(hydroxymethyl)aminomethane are the workhorse pH-control systems in vitro. Unlike phosphate, Tris doesn’t precipitate with calcium or magnesium, which makes it foundational for nucleic-acid work, gel electrophoresis, and protein assays.
The parameters that decide whether Tris fits a protocol — including the two that most often catch people out.
- Eight product lines stocked: TBS, 20X (Tris Buffered Saline), Non-Sterile; Tris Based Transfer Buffers; Tris Based Running Buffers; Tris Based Lysis/Extraction Buffers; Tris Based Washing Buffers; Tris Based Blocking Buffers; Tris-based Buffers; and TE Buffer.
- Buffering range: a pKa of ~8.06 at 25 °C gives strong capacity across roughly pH 7.0–9.0 — the range enzymatic reactions and physiological-range work sit in.
- Divalent-cation compatibility: unlike phosphate, Tris doesn’t complex or precipitate Ca2+ or Mg2+, keeping these enzyme cofactors available.
- Nucleic-acid stabilization: Tris-based systems such as TE maintain a pH that protects DNA/RNA from acid-driven hydrolysis during handling, storage, and electrophoresis.
- Temperature sensitivity (caveat 1): Tris pH drops ~0.028–0.03 pH units per °C rise, so a buffer set to pH 8.0 at 25 °C is meaningfully more alkaline at 4 °C and more acidic at 37 °C. Always pH it at the working temperature.
- Amine reactivity (caveat 2): Tris is a primary amine and can react with aldehydes and participate in some enzymatic reactions — it isn’t inert everywhere.
- When to switch: for amine-sensitive or sub-pH-7.5 work, a Good’s buffer (MES, HEPES, MOPS) may be preferable.
- Buffering speciesTris(hydroxymethyl)aminomethane
- pKa at 25 °C~8.06
- Effective buffering rangeroughly pH 7.0–9.0
- pH shift with temperaturedrops ~0.028–0.03 units per °C rise
- Ca2+ / Mg2+ behaviorno complexing or precipitation
- Buffering below ~pH 7.5poor — consider a Good’s buffer
- Chemical characterprimary amine; reacts with aldehydes
- Nucleic-acid storage systemTE (Tris-HCl + EDTA)
- SDS-PAGE buffer systemdiscontinuous Tris-HCl / Tris-glycine (1970)
- Product lines in this category8
Macromolecules are sensitive to their chemical environment
A pH swing can denature a protein or hydrolyze nucleic acids. Three properties are why Tris became the default matrix — and two more are why it is not the answer to every experiment.
Buffering in the neutral-to-alkaline range
Tris has a pKa of ~8.06 at 25 °C, giving strong capacity across roughly pH 7.0–9.0 — well suited to enzymatic reactions (PCR, restriction digests) and physiological-range work.
Divalent-cation compatibility
Unlike phosphate, Tris doesn’t complex or precipitate Ca2+ or Mg2+, keeping these enzyme cofactors available in solution rather than dropping them out as an insoluble salt.
Nucleic-acid stabilization
Tris-based systems (e.g., TE) maintain a pH that protects DNA/RNA from acid-driven hydrolysis during handling, storage, and electrophoresis.
Caveat 1 — temperature dependence
Tris pH is strongly temperature-dependent: it drops ~0.028–0.03 pH units per °C rise. A buffer set to pH 8.0 at 25 °C is meaningfully more alkaline at 4 °C and more acidic at 37 °C. Always pH it at the working temperature.
Caveat 2 — Tris is not inert
Tris is a primary amine and can react with aldehydes and participate in some enzymatic reactions, so it isn’t inert everywhere.
When a Good’s buffer is the better call
For amine-sensitive work, or for anything below about pH 7.5 where Tris buffers poorly, a zwitterionic Good’s buffer (MES, HEPES, MOPS) may be preferable.
The mistake that quietly shifts every result
Titrating Tris on the bench at room temperature and then running the experiment in a 4 °C cold room or a 37 °C incubator. Because the pH moves ~0.028–0.03 units for every °C, the buffer that read pH 8.0 while you made it is not pH 8.0 where the enzyme actually works. Set the pH at the working temperature, not the convenient one.
How Tris became the default molecular-biology buffer
Four developments explain both why Tris is everywhere and why the zwitterionic alternatives exist alongside it.
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1
Pre-1950s Inorganic and barbiturate buffers
Biochemists relied on inorganic buffers (phosphate, bicarbonate) and toxic barbiturate (barbital/veronal) systems, which often interacted with samples or precipitated with metal cofactors. Significance: this exposed a real gap — no clean, metal-compatible buffer for the neutral-to-alkaline range.
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2
1946 Gomori publishes the amine buffer recipes
George Gomori published buffer recipes for pH 6.5–9.6, introducing organic amine buffers (including Tris) as alternatives to the incompatibility problems with metal ions of phosphate and carbonate. Significance: this put Tris and related amine buffers on the map for biological use.
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3
1950s–1970s Adoption as the standard matrix
Tris became widely adopted for its high water solubility, relative inertness, and buffering in the physiological-to-alkaline range. By the 1970s, it was the standard matrix for DNA extraction, SDS-PAGE, and Western blotting. Significance: this established Tris as the default molecular-biology buffer.
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4
1966 Good’s buffers define the alternatives
Good and colleagues defined the criteria for ideal biological buffers and introduced the zwitterionic “Good’s buffers” (MES, HEPES, MOPS, etc.). Significance: this provided alternatives for applications where Tris’s known drawbacks (temperature sensitivity, amine reactivity, poor buffering below ~7.5) are a problem.
The Tris parameters that decide a purchase
Every value below is as published in the category description for this product family. Use the table to translate a chemistry requirement into a product line.
| Parameter | Value / behavior | What it governs at the bench |
|---|---|---|
| pKa (25 °C) | ~8.06 | Sets the centre of the buffering window; capacity falls away on either side |
| Effective buffering range | roughly pH 7.0–9.0 | Enzymatic reactions (PCR, restriction digests) and physiological-range work |
| Temperature dependence | drops ~0.028–0.03 pH units per °C rise | A buffer set to pH 8.0 at 25 °C is more alkaline at 4 °C and more acidic at 37 °C — pH it at the working temperature |
| Ca2+ / Mg2+ compatibility | does not complex or precipitate them | Keeps divalent enzyme cofactors available — the property phosphate lacks |
| Nucleic-acid handling | maintains a pH that protects DNA/RNA from acid-driven hydrolysis | Handling, storage, and electrophoresis — the basis of TE buffer |
| Chemical reactivity | primary amine; can react with aldehydes and participate in some enzymatic reactions | Not inert everywhere — check amine-sensitive chemistries before substituting |
| Buffering below ~pH 7.5 | poor | Sub-pH-7.5 or amine-sensitive work — a Good’s buffer may be preferable |
Which line for which bench workflow
Select a workflow to see what the source lists for it, and which product line serves it.
- SDS-PAGE
- Native-PAGE
- TAE/TBE nucleic-acid gels
- Lines: Tris Based Running Buffers (protein electrophoresis) and Tris Based Transfer Buffers (Tris-Glycine electroblotting matrix for membrane transfer)
- Western blots
- ELISAs
- Background rinsing — clearing non-specific signal and unbound antibodies from membranes and microplates
- Lines: TBS, 20X (Tris Buffered Saline), Non-Sterile; Tris Based Washing Buffers; Tris Based Blocking Buffers (phosphate-free, for phosphoprotein assays)
- TE buffer for protecting DNA/RNA from hydrolysis
- Long-term DNA/RNA storage — EDTA chelates the divalent cations that nucleases require
- pH protection during handling, storage, and electrophoresis
- Line: TE Buffer
- pH stability during detergent-mediated cell disruption
- Total protein extraction
- Line: Tris Based Lysis/Extraction Buffers
- PCR
- Ligation
- Restriction digestion buffers
- Lines: Tris-based Buffers — versatile benchtop dilutions, enzymatic assay tuning, and custom master mixes
How the Tris-based lines compare
The core basis of each line and the workflow it is intended for, reproduced from the category description.
| Product | Core Basis | Best Use |
|---|---|---|
| TBS, 20X (Tris Buffered Saline), Non-Sterile | Concentrated Tris-HCl + NaCl | Concentrated stock for long shelf-life; diluted to 1X as the universal wash/antibody-dilution base for Western blots and ELISAs |
| TE Buffer | Tris-HCl + EDTA | Long-term DNA/RNA storage — Tris buffers against acid hydrolysis while EDTA chelates the divalent cations that nucleases require |
| Tris-Based Transfer Buffers | Tris-Glycine electroblotting matrix | Protein membrane transfer — conducts current in wet-tank or semi-dry Western transfers, driving proteins onto membranes |
| Tris-Based Running Buffers | Conductive Tris ion matrix | Protein electrophoresis — stable conductive environment for resolving protein lysates in polyacrylamide gels |
| Tris-Based Lysis/Extraction Buffers | Tris-HCl + surfactants | Total protein extraction — pH stability during detergent membrane disruption |
| Tris-Based Washing Buffers | Tris-saline + mild detergent | Background rinsing — clears non-specific signal and unbound antibodies from membranes and microplates |
| Tris-Based Blocking Buffers | Tris-saline + passivating proteins | Phosphoprotein assays — phosphate-free blocking avoids the background problems phosphate buffers can cause in phospho-specific detection |
| Tris-Based Buffers (general) | Purified Tris core | Versatile benchtop dilutions, enzymatic assay tuning, and custom master mixes |
Frequently asked questions
The questions that come up most often when a Tris buffer meets a bench protocol.
Primary literature behind the Tris buffer system
The published sources behind the chemistry and the chronology above.
- Gomori, G. (1946). Buffers in the range of pH 6.5 to 9.6. Proceedings of the Society for Experimental Biology and Medicine, 62(1), 33–34. — Introduced Tris and related organic amine buffers as metal-compatible alternatives to phosphate and carbonate.
- Good, N. E., Winget, G. D., Winter, W., Connolly, T. N., Izawa, S., & Singh, R. M. M. (1966). Hydrogen ion buffers for biological research. Biochemistry, 5(2), 467–477. — Defined the criteria for ideal biological buffers and introduced the zwitterionic “Good’s buffers”; essential context for when to use Tris vs. alternatives.
- Laemmli, U. K. (1970). Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature, 227(5259), 680–685. — The discontinuous Tris-HCl/Tris-glycine buffer system underlying modern SDS-PAGE.
- Sambrook, J., & Russell, D. W. (2001). Molecular Cloning: A Laboratory Manual (3rd ed.). Cold Spring Harbor Laboratory Press. — The standard bench reference for Tris-based buffers in molecular biology (TE, TAE, TBE, TBS recipes and use).
- Bates, R. G. (1973). Determination of pH: Theory and Practice (2nd ed.). Wiley. — Authoritative treatment of buffer pH measurement and temperature dependence — directly relevant to Tris’s strong temperature sensitivity.
