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Biological Buffers

Biological Buffers Selection Guide

We are a world leader in manufacturing and distribution of high quality biological buffers with the expertise and capacity to meet our customer’s needs ranging from a few grams to metric tons. Use our interactive biological buffers selection guide below to help find the right buffer by pH, grade, packaging type, or application.

Refer to the Buffer Reference Center to prepare specific buffer solutions by pH and pKa.

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Biological Buffers Selection Guide by pH


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  What are biological buffers?

By definition, biological buffers are organic substances that maintain a constant pH over a given range by neutralizing the effects of hydrogen ions. In the body, buffers provide a pH environment conducive to critical biochemical processes.

Buffers are ubiquitous in modern biology labs, especially in applications involving protein electrophoresis to view the results of a technique such as the polymerase chain reaction or Western blotting. They are a vital component for modeling biological systems and have many uses in cell culture, molecular biology, nucleic acid and protein purification, and transformation and transfection.


  What is an example of a buffer solution?

Two common chemistry buffer examples are tris(hydroxymethyl)aminomethane (tris) and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), and many others are listed below.


  What is a buffering range?

A buffering range or buffer range indicates the pH level that a buffer maintains over the course of an experiment.


  What are the different types of buffers?

Buffers are typically classified into seven main groups based on the R-group in their chemical makeup and the pH range of their effectiveness. They can be further delineated by grade. At the acidic end of the pH scale, at a range from 5.5 to 8.3 are the morpholinic buffers such as MES, MOPS, and MOBS. Tris is a mid-range buffer stable at pH of 7 to 9.6. Cyclohexylamino buffers such as CHES and CAPS are effective at higher pH values from 8.6 to 11.4.