Morpholine propane sulfonic acid MOPS and morpholine ethanesulfonic acid MES are two commonly used buffers in biochemical experiments, both of which can stabilize the pH value of the system. The chemical structure of the two is also very similar, and the buffer range is slightly different. Therefore, the method of preparing a buffer solution is similar.

Morpholine propanesulfonic acid MOPS performance application and preparation:
MOPSBuffer, namely 3-morpholinopropanesulfonic acid buffer, as a biological buffer, the buffer pH range is between 6.5 and 7.9, suitable for electron transport and phosphorylation studies of chloroplast thin-layer preparation; it can be formulated into a variety of agar cultures It can be used as a non-toxic buffer in the minimal medium for the cultivation of Streptomyces coryneformis and the production of cephalosporins; it can be used as the electrolyte system component of two-dimensional gel electrophoresis and isoelectric focusing electrophoresis (IEF); it can also be used for RNA Blot hybridization NorthernBlot, as a buffer for nucleic acid RNA isolation and transfer membrane. To

Morpholine propane sulfonic acid MOPS and Morpholine ethanesulfonic acid MES

The commonly used 10×MOPSBuffer preparation methods are as follows:
(1) Weigh 41.8g MOPS and dissolve it in about 700mL DEPC treated water;
(2) Use 2NNaOH to adjust the pH value to 7.0;
(3) Add 20 mL of DEPC-treated 1M NaOAc and 20 mL of 0.5 MEDTA (pH 8.0) to the solution;
(4) Dilute the volume to 1L, filter to remove impurities with a 0.45um filter membrane, and store at room temperature away from light. It is enough to dilute 10 times the concentration when using.

Morpholine ethanesulfonic acid MES performance application and preparation:

MES is the common name for the compound 2-(N-morpholino)ethanesulfonic acid. Its chemical structure contains a morpholine ring. It has a molecular weight of 195.2 and the chemical formula is C₆H₁₃NO₄S. Synonyms include: 2-morpholinoethanesulfonic acid; 2-(4-morpholino)ethanesulfonic acid; 2-(N-morpholino)ethanesulfonic acid; 2-(4-morpholino)ethanesulfonic acid; MES; MES hydrate; and morpholine-4-ethanesulfonic acid hydrate. MOPS is a similar pH buffering compound which contains a propanesulfonic moiety instead of an ethanesulfonic one.

MES Buffer, namely 2-morpholineethanesulfonic acid, the buffer range of the buffer is pH5.5-6.7, the pKa value of the MES buffer is close to the physiological pH, and it is used in the mobile phase of the active amino gel chromatography column to separate brain tubulin. Ingredients: MES cannot be absorbed when passing through cell membranes, and can transmit ultraviolet light. This type of biological buffer is commonly used in the culture of plant cells.
Configuration method: The configuration of MES buffer is the same as most other buffers. Assuming the configuration of 1L MES buffer with a pH of 6 and a concentration of 100mM:
(1) Weigh 0.1mol or 19.5g MES and dissolve it in 500mL DEPC water
(2) Adjust the pH to 6.0 with 1N or 10N NaOH solution
(3) Dilute to 1L and store at 4°C.

Applications

MES is used as a buffering agent in biology and biochemistry. It has pK_a value of 6.15 at 20 °C. The pH (and pK_a at ionic strength I≠0) of the buffer solution changes with concentration and temperature, and this effect may be predicted using online calculators.^[1] MES is highly soluble in water. The melting point is approx. 300 °C.

MES was developed as one of Good's buffers in the 1960s. These buffers were developed with the following criteria in mind: midrange pK_a, maximum water solubility and minimum solubility in all other solvents, minimal salt effects, minimal change in pK_a with temperature, chemically and enzymatically stable, minimal absorption in visible or UV spectral range and reasonably easily synthesized.^[2] MES is also useful as a non-coordinating buffer in chemistry involving metal ions, as many common buffers (e.g. phosphate and acetate) readily form coordination complexes. MES only weakly binds Ca, Mg, Mn, and it has negligible binding with Cu(II). ^{[2] [3]}

Safety

Contact with this buffer is hazardous;^[4] skin or eye exposure should be cleaned well with water and medical aid should be sought in the case of eye exposure, swallowing or inhalation of dust. It also emits toxic fumes upon combustion, including carbon monoxide, nitrogen oxide and sulfur oxides.

Features of MES Buffered Saline Packs:

• MES buffer—dissolved in 500 mL of water, each pack makes 0.1M MES, 0.9% sodium chloride, pH 4.7
• Convenient—dissolve contents of one envelope in water and the buffer is ready to use
• Save time and trouble—no weighing, no pH adjustment, no need to stock individual components, and no need to make and store large volumes of stock solution in advance of daily needs
• Long shelf life—stocking and storage as dry packs eliminates concerns about long-term stability of stock solutions
• Eliminate variables—our quality control ensures that every pack will yield the same, consistent buffer

BupH Dry-Blend Packs of MES buffered saline are easy to use. Simply empty contents of one foil envelope pack into a beaker, add ultrapure water and stir to dissolve. The packs eliminate weighing time and tedious pH adjustments. When dissolved in 500 mL of water, each pack makes 0.1M MES, 0.9% sodium chloride, pH 4.7. MES is 2-(N-morpholino) ethanesulfonic acid.

Applications:
• Carboxyl-to-amine crosslinking procedures using carbodiimide crosslinker EDC (Part No. 22980)

The biological buffers(powder) produced by our company mainly include the following types.