HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid ) is a zwitterionic organic chemical buffering agent; one of the twenty Good's buffers. HEPES is widely used in cell culture, largely because it is better at maintaining physiological pH despite changes in carbon dioxide concentration (produced by cellular respiration) when compared to bicarbonate buffers, which are also commonly used in cell culture. The dissociation of water decreases with falling temperature, but the dissociation constants (pK) of many other buffers do not change much with temperature. HEPES is like water in that its dissociation decreases as the temperature decreases. This makes HEPES a more effective buffering agent for maintaining enzyme structure and function at low temperatures. Lepe-Zuniga et al. reported a phototoxicity of HEPES when exposed to ambient light by the production of hydrogen peroxide, which is not a problem in bicarbonate-based cell culture buffers. It is therefore strongly advised to keep HEPES-containing solutions in darkness as much as possible.

CAS：7365-45-9
中文别名：N-(2-羟乙基)哌嗪-N\'-2-乙烷磺酸;4-(2-羟乙基)-1-哌嗪基]乙磺酸;N-2-羟乙基哌嗪-N\'-2-乙磺酸;N-2-羟乙基哌嗪-N\'-2-乙磺酸(HEPES);4-(2-羟乙基)-1-哌嗪乙磺酸;羟乙基哌嗪乙磺酸;N-(2-羟乙基)哌嗪-N’-2-乙烷磺酸;
英文别名：GOOD\'S BUFFER;HEPES.1/2Na;EIT hydrobromide;HEPES,1M solution;hepesfreeacid;HEPES BUFFER PH 8.0;HEPES;hepes solution;
分子式：C8H18N2O4S
分子量：238.305
精确质量：238.099
Psa：89.46
Logp：-0.5593

MDL号：MFCD00006158

外观与性状：白色结晶粉末
密度：1.07g/mLat 20°C
熔点：234-238 °C
折射率：n20/D 1.339
水溶解性：Soluble
稳定性：Stable. Combustible. Incompatible with strong oxidizing agents. Protect from moisture.
储存条件：2-8ºC

RTECS号：TL6809000
安全说明：S24/25-S22-S36-S26
危险类别码：R36/37/38
WGK Germany：1
海关编码：29335995
危险品标志：Xi

用途
本品是一种氢离子缓冲剂，能较长时间控制恒定的pH范围。