Friends and fellow scientists,
Whenever I and any of lab colleagues are preparing the MS solution for preparing the MS media, we make up the volume to 1L and check the pH (around 3.8-4.1) and when trying to bring it to 5.6-5.8 by adding 0.1 N NaOH the salts tends to get precipitated to the bottom of the flask!!..Dont know what to do..It is the same with readymade MS salts as well...Please see the image. (Bottom white precipitation after few mins.)
very strange indeed.
I only got white precipitation when CaCl was disturbing, as the Ca combined with the OH of th NaOH added for adjusting the pH.
Why is the pH so low after preparing the 1 l? which water do you use. Bidest? As the pH is with my preparation always above 4.
And maybe you do not start to add 0.1 N NaOH at once....
Is there any problem might be with the pH meter, since when the same I tested with litmus was showing a pH of 6.8!! strange indeed...Dr. Wenkart..what is pH of your Growth regulators stock...both for NAA and BAP and how you prepare them i.e. either in Ethanol or NaOH for NAA and HCl for BAP?
You really have a point there and I had been thinking of it after sending my answer. MACHINES like to get unreliable, pity. But they are. Thats why it is good alsways to check with pH paper, those little stripes changing the colour when it contact to the liquid medium.
The plant hormones are in liquid without adjusted pH.
Given to the medium in small concentration, e.g. o.1-0.5 ppm does not change the pH of the medium.
Only IBA could as it is used in more than 1 ppm final concentration of the medium.
I used long time ago to dissolve all the hormones in pure EtOH. thus it could be kept in the fridgeall the time.
Later I did start to dissolve the weight powder in DMSO, hot, on the plate, small amount of it, and at once to add hot bidest. and later fill up to the desired stock solution.
NaOH 1N is used to make the stock solution of Kinetin.
Dr. Wenkart while making kinetin, do you use 1N NaOH only to make the stock to 100mL or just a few mL to dissolve it and make up the volume to 100mL. Eg.
If you want to prepare stock of 100mg/100mL then would you use 1N NaOH 100mL or just a few mL of 1N NaOH and make up the volume to 100mL with DW?
We started with kinetin to use a stock solution of 500micro M and I continued
with it.
For 100ml 500microM Kinetin you weigh 10.76 mg.
Add 1.8 ml of 1N KOH. Wait till it has dissolve and fill up to 100 ml with DW.
I never did a stock solution with 100 mg in 100 ml. One has to check how much of the kinetin is suluable in 100 ml...
Which iron do you use? If you use the ready made powder of Sigma e.g. the iron is already included. Thus I do not understand. Tell me.
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