When we use the good's buffer, we always inadvertently confuse the HEPES and pipes in the good's buffer, thinking that they are the same, which makes it impossible to distinguish them very accurately. In fact, there are similarities between them, but there are also many different characteristics.
Especially in the process of our experiment, a little difference may lead to the failure of the experiment. So we need to know what buffer is and what it does? In order to distinguish between HEPES and pipes in buffer, what is the difference between them? What should we pay attention to when using?
Buffer solution is a kind of special buffer system for life science research. In biochemical experiments, buffer solution plays an indispensable role. It can resist the influence of a small amount of strong acids and bases, and maintain the pH value closest to the physiological environment for the system. HEPES and pipes buffers are commonly used in biological experiments.
Package picture of Desheng biological buffer
The pH buffer range of HEPES is 6.8-8.2, which is a kind of zwitterionic biological buffer. It is soluble in water and does not form stable complexes with metal ions. In most cases, it does not interfere with biochemical processes. It can be widely used in a variety of biochemical reactions and used as a buffer reagent in some cell culture media.
HEPES is commonly used in cell culture media of various types of organisms; in protein research, it is often used as the component and eluent of binding buffer in cation exchange chromatography; in DNA research, it is used as the buffer of calcium phosphate and DNA sediment formation system, AFM and electroporation experiment.
In addition, HEPES interferes with the reaction between DNA and restriction enzyme and is not suitable for Lowry's method. HEPES buffer is often used in the research of organelles and pH sensitive proteins and enzymes, as well as in biochemical diagnostic kits, DNA / RNA extraction kits and PCR diagnostic kits. It is a hydrogen ion buffer, which can control the constant pH range for a long time. When the final concentration is 10-50 mmol / L and the culture medium contains 20 mmol / L HEPES, the buffer capacity can be achieved.
The pH buffer range of pipes is 6.1-7.5, insoluble in water and soluble in NaOH solution. Different from buffers containing bis (2-hydroxyethyl) amino groups (such as bis Tris, bicine), pipes can not form stable complexes with most metal ions, so it is suitable for buffers containing metal ions.
According to previous studies, PIPES can be used to purify tubulin by using cellulose phosphate chromatography, and to purify recombinant GTP binding protein ARF1 and ARF2 by gel filtration as a buffer to crystallize ketoenzyme from E. coli. In addition, due to the formation of free radicals, pipe is not suitable for redox system. In cation exchange chromatography, low concentration of pipes buffer should be used because of its relatively high ionic strength and concentration dependent pKa value.
It can be seen that neither pipes nor HEPES can form stable complexes with metal ions, which is suitable for the solution containing metal ions. However, there are some differences between them. In terms of solubility, pipe is insoluble in water, while HEPES has good water solubility. In terms of buffer range, pipe is acidic to neutral, and HEPES is neutral to alkaline. This is mainly due to the structural differences between them. Pipe has two sulfonic groups, and HEPES contains one sulfonic group and hydroxyl group.
In addition, pipes and HEPES have some limitations in the application of some systems. Therefore, when we choose the above buffers, we need to consider the suitability of the experimental system and the difference of their properties.
We should learn to distinguish and understand the similarities and differences in these reagents, so as to better promote the R & D and production of our different products. Desheng consistently adheres to this kind of subtle difference, so as to continuously develop and produce better products.
