Powder is cheaper indeed. Just dissolve the salt, i.e.: Trizma base from Sigma or any other supplier, into MiliQ water at the wanted concentration and adjust the pH with HCl. Then you can sterilize it with the autoclave in a closed bottle. And ready to use.

You can look for some reference from this wikipedia link

http://en.wikipedia.org/wiki/Tris-buffered_saline

and from one of the previous questions from research gate

https://www.researchgate.net/post/What_is_the_difference_between_tris-Hcl_and_tris_base

and some detailed instruction can be found here:

http://chemistry.about.com/od/acidsbases/a/trisbuffer.htm

In short, you can dilute the tris powder to MQ-water and adjust the pH with HCl or NaOH, and add some NaCl if you want a more physiological salt concentration. Yes, you can put it to autoclave or filter it if you need sterile buffer.

I am agree with Antonio, that the powder is cheaper. you can buy the tris (anhydrous) from other company, of suitable grade as per your need e.g. analytical, molecular, DNA free etc. Better is to prepare high conc. of the solution say 1 molar and then dilute it to your required conc. this will reduce the chances of getting error in weighing.

Its a very routine process in our lab. We never purchase the solution. You need to know the molarity of the solution before going into the details. Lets consider it 1M, pH 9 and you need to prepare 1Lt. Molecular weight of Tris base is 121.14. Considering the above data, we need to weigh 121.14 gm of tris base and dissolve it into 900 ml of milli Q water. The pH at this stage is approx. 10.6. When it become homogenous solution, adjust the pH using 6M HCl dropwise until pH 9. Adjust the final volume to 1000 ml (1Lt) and autoclave the solution. The solution is ready to use. All the best. ;)

Thats pretty standard, also the autoclaving. However, I wouldn't recommend using Tris at pH 9, because this is at the upper end of the buffering range (which goes from 7 to 9), meaning, there is no buffer capacity left, when you get more basic. This will cause the pH to change fast into the direction of being more basic...

For a desired pH around 9, I would recommend using CHES, which has a buffering range of 8,5 to 10. For reference see the buffer reference page by Sigma: http://www.sigmaaldrich.com/life-science/core-bioreagents/biological-buffers/learning-center/buffer-reference-center.html

or page 320 in the LabFaQ (which I can recommend anyway): http://www.roche-applied-science.com/wcsstore/RASCatalogAssetStore/Articles/12115972001_10.11.pdf

Dear Christian,

Yes you are right; but as I want to use Tris buffer for adjusting the pH of a bacterial solution which is tending to get basic by bacterial activity, this is important for me to prevent increasing pH higher than 9. Actually the desired pH range is 8.5-9.

Then I would use a substance which has a useful buffer range. The Sigma table I linked above sorts them by the useful pH, AMPD and TAPS should be useful for you. Tris is standard because it buffers between 7and 9, which is useful for maintaining conditions for living cells.

For 0.13M tris buffer solution preparation, i added 15.75g tris powder into 800ml disttiled water and then adjusted pH to 9 using HCl solution. Then i diluted it by adding 200ml water. The dilution doesn't change the pH adjustment?

There is a tool for making Tris buffers using Henderson-Hasselbalch Calculator:

http://www.cytographica.com/lab/HHTris.html

I am agree with Christian , that using Tris at pH 9, because this is at the upper end of the buffering range (which goes from 7 to 9)