The biological buffer PIPES-NA, also known as Sodium hydrogen piperazine-1,4-diethanesulphonate, is a commonly used amphoteric ion buffer. The following is an introduction to its basic information: Chemical properties: The molecular formula of PIPES-NA is C8H17N2NaO6S2, with a molecular weight of 324.35. It is a white powder with a content of up to 99%. Solubility: Although its solubility in water is poor, PIPES-NA often uses sodium hydroxide solution for dissolution. Buffering capacity: PIPES-NA has good buffering capacity within the pH range of 6.1 to 7.5. Application scope: PIPES buffer can be used as a buffer for fixing plant cells under electron microscopy, as well as a dimethyl arsenate buffer instead of ju toxin. It can also be applied in experiments to purify microtubule proteins using cellulose phosphate chromatography. Note: Due to the ability of PIPES buffer to form free radicals, it is not recommended to use it in redox reactions. Its relatively large ion strength and concentration dependence on pKa value require special attention to the concentration of PIPES when used in some experiments. For example, in cation exchange chromatography experiments, if PIPES buffer is used, the concentration should be lower, otherwise it may affect the experiment.