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PBS的配制

作者:高考题库网
来源:https://www.bjmy2z.cn/gaokao
2021-02-10 03:15
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2021年2月10日发(作者:northward)


PBS


标准配方如下(


1L




成分





分子量





终浓度(


mM




用量(


g





近似用量(


g




半数用量(


g

< br>)



NaCl





58.44




137





8.006




8.00




4.00


KCl





74.551






2.7




0.201




0.20




0.10


Na


2


HPO


4

·


12H


2


O


358.14





10





3.581




3.58




1.79


KH

2


PO


4





136.086






1.76




0.240




0.24




0.12


理论上需要调


pH


,但在实际操作中,用蒸馏水或者超纯水配制后,


pH

< br>在


7.3


左右,所以通常不用调


pH




10


×


PBS


配方如下(


1L





成分




< /p>


近似用量(


g




NaCl




80.0


KCl





2.0


Na


2


HPO


4


·


12H


2


O


35.8


KH


2

PO


4






2.4


10


×


PBS


保存于

< br>4


℃时,会析出晶体,且不易复溶,因此


10

< p>
×


PBS


要在室温保存。



PBS


在室温保存时容易长菌,应保存于


4


℃。





关于


PBS


配方的比较与讨论:



我们平时会用到


PBS

,但网上


PBS


的配方有多种,不知如何选择?

< p>




参考一:



看你的用途了。配方虽然有 多种,但在



等渗


< br>这个概念上相差都不大。常见的配方一般有三种:



1< /p>



0.9%


的生理盐水

< br>


有些人也把它叫做


PBS


,实 际上是错误的概念,它并没有


“PB”


,没有缓冲能力,纯化少 用。



2



p H7.3



137mM NaCl



2.7mM KCl



10mM Na


2

< p>
HPO


4



1.8mM KH


2


PO


4




经验证,这种配方是没有办法加钙离子和镁离子的,会形成 沉淀。此配方为


0.01M



PBS< /p>


,所对应的


质量分别为


8g


NaCl



0.2g


KCl



1.44g



1.42g



Na


2


HPO


4



0 .24g



0.27g



KH


2


PO


4


。考虑到


Na


2


HPO


4


通常



Na


2


HPO


4


·


12H20


,所以应该加


3.58g



(修正过的)




这个配方比较常用的,含


K


,特别在分 子生物学上常用。通常所说的浓度


0.01M


指的是缓冲溶液中 所


有的磷酸根浓度,而非


Na


离子或< /p>


K


离子的浓度,


Na

离子和


K


离子只是用来调节渗透压的。如果是用于免


疫组化的话,则需要在配置的时候分别加入


100u/ml

< p>
青霉素和链霉素之后再调


pH


、定容、灭菌消毒。



3



pH7 .2



7.4



20mM PB



150mM NaCl

< br>这个配方是蛋白质纯化常用的


PBS


,配制起来比较方便 。



具体到称量方面,要注意试剂是否有结晶水,分子量是不同的。



参考二:



关键看用途,如果是要活性 ,要考虑你的目的蛋白在什么样的环境下稳定,主要是掌握好钠钾平衡和


生理状态下离子 强度,在此前提下有一定的缓冲能力。




参考三:



PBS



phosphate- buffered saline


的意思。



看看下面这个,或许对你有用



Applications


PBS has many uses because it is isotonic and non-toxic to cells. It can be used to dilute substances. It is used


to


rinse


containers


containing


cells.


PBS


can


be


used


as


a


diluent


in


methods


to


dry


biomolecules,


as


water


molecules within it will be structured around the substance



protein, for example




to be 'dried' and immobilized to


a solid surface. The thin film of water that binds to the substance prevents denaturation or other conformational


changes. Carbonate buffers may be used for the same purpose but with less effectiveness. PBS can be used to take a


reference spectrum when measuring the protein adsorption in ellipsometry.



Additives can be used to add function. For example, PBS with EDTA is also used to disengage attached and


clumped cells. Divalent metals such as zinc, however, cannot be added as this will result in precipitation. For these


types of applications, Good's buffers are recommended.


Preparation


There


are


many


different


ways


to


prepare


PBS.


Some


formulations


do


not


contain


potassium,


while


others


contain calcium or magnesium. One of the most common preparations is described below.


The simplest way to prepare a PBS solution is to use PBS buffer tablets. They are formulated to give a ready


to use PBS solution upon dissolution in a specified quantity of distilled water. They are available in the standard


volumes: 100, 200, 500 and 1000 ml.


A 10 liter stock of 10x PBS can be prepared by dissolving 800 g NaCl, 20 g KCl, 144 g Na


2


HPO


4


and 24 g


KH


2


PO


4


in 8 L of distilled water, and topping up to 10 L. The pH is ~6.8, but when diluted to 1x PBS it should


change to 7.4. When making buffer solutions, it is good practice to always


measure the pH directly using a pH


meter. If necessary, pH can be adjusted using hydrochloric acid or sodium hydroxide. On dilution, the resultant 1x


PBS should have a final concentration of 137 mM NaCl, 2.7 mM KCl, 10 mM Sodium Phosphate dibasic, 2 mM

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