Choosing the right biological buffer for the experiment can be a difficult task. There are many options available (Hepes, Mops, Tris, Bis-Tris, etc.), which can easily cause confusion.
After understanding these challenges, Desheng has prepared a short list for your reference when choosing buffer salts for research:
1. Buffer range
Each buffer reagent has a pH range with the strongest buffer capacity. This buffer capacity is usually determined by the pKa of the buffer reagent. You must choose a buffer with a pKa value close to the middle of the desired range (typically, it is recommended to use a buffer with a pKa value that is at least within one pH unit of the target pH).
The applicable pH range of each buffer
2. pH changes during the experiment
Considering in advance whether the pH value may increase or decrease during the experiment is critical to the selection of buffers. If you think the pH will increase during the experiment, you must choose a buffer with a pKa slightly higher than the optimal value at the beginning of the experiment. The opposite is also true: if you think the pH will decrease, choose a buffer with a lower pKa.
3. Buffer concentration
The buffer concentration must be adjusted to have sufficient buffering capacity for the experimental system. In general, if the buffer concentration is too low, the pH of the solution cannot be stabilized. Conversely, if the concentration is too high, the buffer is likely to affect the experiment. Generally, it is recommended to use a concentration higher than 25mM.
For systems in which hydrogen proton exchange is not active, a concentration of 25-100mM is generally recommended. For systems where proton exchange may occur, it is recommended to use a buffer concentration 20times higher than the molar concentration of the protons exchanged.
When preparing a buffer solution, remember to adjust the solution concentration to the intended use concentration.
4. Temperature change
You must set the pH of the buffer solution according to the temperature at which the experiment will be performed. The temperature directly affects the pKa of the buffer, and thus the pH and buffering capacity of the system. This situation may be critical in biological systems, where accurate hydrogen ion concentrations are required for the reaction system to operate at maximum efficiency.
The pKa of some buffers (such as PIPES) is less sensitive to temperature changes, but other options (such as TRIS, ACES, TAPS, TES, or Tricine) are more affected by these changes.
The figure below shows the approximate pKa change according to the temperature of Desheng Biobuffer:
Approximate pKa change of Desheng Biobuffer Temperature
Desheng is one of the largest manufacturers of biological buffers in the world. Our products are shipped daily to top research centers and biotechnology companies in Europe, America and Asia. Our products are independently developed and produced. We can provide products that meet the quality and packaging requirements of our customers. We provide small packages and bulk packages (from grams to tons). They can be delivered worldwide to assist transportation, and provide comprehensive and powerful after-sales service. Looking forward to your call for further consultation! Tel: +86-711-3702650. Website: www.vacutaineradditives.com.
