Bouin's Fixative Solution Boui

Bouin's Fixative Solution Bouin's 固定液 波恩氏液

产品简介 

固定的目的在于保存细胞和组织的原有形态结构，固定剂能阻止内源性溶酶体酶对自身组织和细胞的自溶、抑制细菌和霉菌的生长。固定剂通过凝固、生成添加化合物等使蛋白质内部结构发生改变，从而使酶失活。固定液主要分为醛类固定液、汞类固定液、醇类固定液、氧化剂类固定液、盐类固定液等，较为常用的是醛类中的福尔马林、醇类中的乙醇。

Bouin's固定液(Bouin's Fixative)主要由PA、甲醛、乙酸混合而成，PA可沉淀蛋白引起组织收缩，但不会使组织硬化, 其与甲醛和乙酸混合后，穿透速度加快，固定均匀，组织收缩轻微，对细胞的微细结构显示的很清晰，为一种良好的固定液。尤其对Masson三色法等的结缔组织和肌纤维染色有媒染作用，经其固定后的组织着色鲜艳。该固定液也可能软化皮肤和肌腱，以利于切片。

 

使用参考 

1、按实验具体要求操作。

2、一般仅需固定30~60min。如果组织块大，可适当延长固定时间，但不宜超过24h。

3、用Bouin固定液固定后，组织可稍微流水冲洗或不冲洗直接转入70%的乙醇脱水，经乙醇脱水时可除去大部分PA，组织留有一点黄色，对染色也无影响。

 

注意事项 

1、Bouin's固定液对人体有一定的损害，请在通风好的环境下小心操作，避免吸入。

2、组织取材的厚度不同，固定时间也不同，对组织恰当的选材有利于固定液的渗透。常规活检组织比较适合的厚度为2~4 mm，一般不超过6 mm。

3、固定液的容量应足够，一般固定液与组织块的体积比率应大于10：1。如果容积不够大，可以在固定期间更换1~3次固定液。

4、温度对固定的影响很明显，提高温度可以加速固定作用，但温度不宜过高。

5、取出新鲜组织后，应及时固定，无法及时固定时，应保存于生理盐水中及时送检。

 

Bouin solution, or Bouin's solution, is a compound fixative used in histology. It was invented by French biologist Pol Bouin and is composed of picric acid, acetic acid and formaldehyde in an aqueous solution. It is especially good for gastrointestinal tract biopsies because this fixative allows crisper and better nuclear staining than 10% neutral-buffered formalin. It is not a good fixative when tissue ultrastructure must be preserved for electron microscopy. However, it is a good fixative when tissue structure with a soft and delicate texture must be preserved. Formalin-fixed tissue is normally mordanted with Bouin solution for better staining results in the trichrome stains. The acetic acid in this fixative lyses red blood cells and dissolves small iron and calcium deposits in tissue. A variant in which the acetic acid is replaced with formic acid can be used for both fixation of tissue and decalcification.

The effects of the three chemicals in Bouin solution balance each other. Formalin causes cytoplasm to become basophilic but this effect is balanced by the effect of the picric acid. This results in excellent nuclear and cytoplasmic H&E staining. The tissue hardening effect of formalin is balanced by the soft tissue fixation of picric acid. The tissue swelling effect of acetic acid is balanced by the tissue shrinking effect of picric acid.

When using Bouin solution, several potential problems can arise. Due to the formalin in the solution, formalin pigment may be present when viewing tissue sections under the microscope. Wet tissue should be fixed in Bouin solution for less than 24 hours. Excess picric acid should be washed out of tissue using several alcohol and water solutions or staining quality may deteriorate over time. Wet tissue fixed in Bouin solution should be stored in an alcohol and water solution rather than Bouin solution. Since Bouin solution contains formaldehyde, picric acid and acetic acid, appropriate safety precautions for these substances should be taken and regulations followed. In particular, noting that picric acid can be explosive, sensitive to friction and shock when dry and in contact with some metals can form unstable metal picrates.