Recently, I always receive customers' inquiries about Good's buffers, but many times even the customers themselves are not able to express their exact products exactly. Because there are still a few people who really understand, I will briefly introduce Good's buffer and the difference between PIPES and HEPES in Good's buffer.
Good's buffers, also known as zwitterionic buffers, are a type of buffer system dedicated to life science research. They do not participate in or interfere with the biochemical reaction process, and have no inhibitory effect on enzyme chemical reactions. Therefore, they are specifically used for organelles and electrodes. Research work on volatile, pH-sensitive proteins and enzymes. These buffer systems should have the following characteristics:
1. The pKa value is between 6-8;
2. High solubility in water;
3. Not easy to penetrate biofilm;
4. Little salt effect;
5. The ion concentration, solution composition and temperature have little effect on dissociation;
6. No complex or precipitation with metal ions;
7. The buffer is chemically stable;
8. Small absorption of light in the ultraviolet and visible wavelength range;
9. Easily produce high-purity salt.
The PIPES and HEPES in Good's buffer are our commonly used buffers, and they are inextricably linked. To a certain extent, they have the function of acquaintance, but they also have their own functions and advantages. After we understand Good's buffer, let’s take a look at PIPES and HEPES, let us slowly penetrate into their respective fields, so that we can be more Good choices use their respective characteristics:
The pH buffer range is 6.1-7.5, insoluble in water, and soluble in aqueous NaOH solution. PIPES is different from buffers containing bis(2-hydroxyethyl)amino groups (such as Bis-tris, Bicine), and cannot form stable complexes with most metal ions. It is suitable for buffers in solution systems containing metal ions. According to the existing research results, PIPES can be applied to the purification of tubulin using phosphocellulose chromatography, the purification of recombinant GTP-binding proteins ARF1 and ARF2 by gel filtration, and as a buffer to crystallize transketolase from E. coli. In addition, because PIPES can form free radicals, it is not suitable for use in redox systems. In cation exchange chromatography, a low concentration of PIPES buffer should be used, because PIPES has a relatively large ionic strength, and its pKa value is concentration-dependent. A
The pH buffer range is 6.8-8.2. It is soluble in water. It is a hydrogen ion buffer that can control a constant pH range for a longer period of time. The final concentration is 10-50mmol/L, and the general culture medium contains 20mmol/L HEPES to achieve buffering capacity. It does not form stable complexes with metal ions, and in most cases, does not interfere with biochemical processes. HEPES is commonly used in cell culture media of various types of organisms; in protein research, PIPES is often used as a combination in cation exchange chromatography Buffer components and eluent; reaction buffer, pre-hybridization buffer, hybridization buffer for separation and analysis of RNA nuclear components; 3′-terminal labeling for RNA and T4RNA ligase; used in biochemical diagnostic reagents In the kit, DNA/RNA extraction kit and PCR diagnostic kit. In DNA research, PIPES is used as a buffer for calcium phosphate and DNA precipitate formation systems, AFM and buffer for electroporation experiments. In addition, HEPES interferes with the reaction between DNA and restriction enzymes, and is not suitable for Lowry's method to determine protein content.
It can be seen that neither PIPES nor HEPES can form stable complexes with metal ions, which is suitable for solution systems containing metal ions. However, there is also a certain difference between them. In terms of solubility, PIPES is insoluble in water, while HEPES has good water solubility; in terms of buffer range, PIPES is acidic to neutral, and HEPES is neutral to alkaline. These are the same and different All tell us that to choose them better, we must first understand them. Desheng already has extensive experience in Good's buffer. It provides you with technology products, teaches you how to choose the right choice to distinguish what you need. Why don't you choose such a company!
