DEPC水你不知道的秘密

一、DEPC物理化学性质

DEPC即二乙基焦碳酸酯，由名可知其为一种酯类，由此可知其一定有水果的香味（易挥发），一定也可以进行水解反应生成醇和酸，具体反应过程如下：

由上述化学结构知其极不稳定，在PH=6的溶液中半衰期为20min，其容易与胺、羟基（蛋白）、咪唑基（RNA）和硫醇反应，因此其能灭活各种酶类，其对人体有害，如果不小心沾到身上，请用大量清水清洗。  

二、使用方法

DEPC有这么强大的功能，那么对于我们RNA提取肯定必不可少，那么如何使用呢？

1. DEPC处理水制备方法：有效DEPC浓度：0.05%-0.1%，处理时间一小时以上，然后高压15min，高压后水果香味越轻越好。注意：在使用DEPC水溶液是浓度不宜过高，首先该浓度下对于处理水溶液中参与的酶已经足够，而且过高的DEPC会有残余的风险。由于DEPC为酯类，其在酸碱溶液中极不稳定，因此在制备DEPC水应该注意水的PH值，

2. DEPC水处理Tip头：用DEPC的水溶液（0.05%-0.1%）处理过夜，然后高压15min。
   

3. 不得使用DEPC水擦拭台面和移液器，不得使用DEPC水配置Tris缓冲液

三、你不知道的秘密

       由上面可知：DEPC处理水中并不含DEPC，因此其在使用过程中一定要防止污染，尽量分装使用。

有研究证明Milli-Q超纯水与DEPC处理水在用来做RNA相关的实验时效果相同。Reference：PMID8643347

文章摘要：The Milli-Q PF Plus water polishing system is equipped with high-purity ion and organic removal media and a capillary fiber ultrafiltration device. The system produces ultrapure water practically free of ribonuclease contamination. The necessity for diethyl pyrocarbonate (DEPC) treated solutions in RNA molecular biological procedures was tested by preparing RNA from a variety of tissues and tissue cultured cells using either DEPC-treated, autoclaved solutions or pure Milli-Q PF water dispensed directly from the system. Tissue sources included rabbit brain, heart, lung, liver, kidney, and bladder as well as cultured human corpus cavernosum smooth muscle cells (HCCSMC). RNA was prepared by solubilization in guanidinium isothiocyanate, phenol/chloroform extraction, and isopropanol precipitation followed by Northern blot analysis. Hybridization with fibronectin (approximately 7.6kb) and glyceraldehyde-3-phosphate dehydrogenase (1.2kb) revealed that water from a Milli-Q PF water system performed as well as DEPC-treated, autoclaved solutions. RNA stability at 37 degrees C was examined for various times using rabbit lung RNA in either DEPC-treated water or Milli-Q PF water. Intact RNA was detected after 6 hours in total RNA and by Northern blots hybridized with fibronectin. There was no significant difference in RNA degradation between DEPC-treated water or Milli-Q PF water. We conclude that Milli-Q PF water is an acceptable substitute to DEPC-treated water for the preparation of RNA and Northern blot analysis.

相信你看完上面的红字部分，你可以发现使用milli-q超纯水和它是一个效果吧，以后不用花钱买这个了吧，又省了一大笔。