Physiological saline is 0.85% Sodium Chloride solution made in water. Some people call 0.9% NaCl  solution made in water as Physiological saline. However PBS refers to 0.9% NaCl solution in Phosphate buffer having KCl. Recipe of PBS

Dissolve the following in 800ml distilled H2O.

 8g of NaCl

 0.2g of KCl

 1.44g of Na2HPO4

 0.24g of KH2PO4



2. Adjust pH to 7.4 with HCl.

3. Adjust volume to 1L with additional distilled H2O.

4. Sterilize by autoclaving.

Physiological saline is 0.85% Sodium Chloride solution made in water. Some people call 0.9% NaCl  solution made in water as Physiological saline. However PBS refers to 0.9% NaCl solution in Phosphate buffer having KCl. Recipe of PBS

Dissolve the following in 800ml distilled H2O.

 8g of NaCl

 0.2g of KCl

 1.44g of Na2HPO4

 0.24g of KH2PO4



2. Adjust pH to 7.4 with HCl.

3. Adjust volume to 1L with additional distilled H2O.

4. Sterilize by autoclaving.

Well calling 0.9% NaCl Physiological saline  is not fair.

I am rather comfortable and did all my yeast experiments in PBS. It is more acceptable to manuscript reviewar and comparable with published data

I think any saline will do the job. But kindly check the pH compatibility of the yeast if u r planning to keep it for long time as most of the yeasts prefer acidic pH.

Normal saline (NS or N/S) is the commonly used phrase for a solution of 0.90% w/v of NaCl, about 300 mOsm/L or 9.0 g per liter. This solution is referred to as physiological saline or isotonic saline. The solution is 9 grams of sodium chloride (NaCl) dissolved on water, to a total volume of 1000 ml. However, Phosphate buffered saline (PBS) is a buffer solution . It is a water-based salt solution containing sodium phosphate (Na2HPO4), sodium chloride (NaCl) and, in some formulations, potassium chloride (KCl) and potassium phosphate (KH2PO4). The most common composition of PBS (simple concentration):

NaCl .......8g/L

KCl .........0.2g/L

Na2HPO4.......1.44g/L

KH2PO4........0.24g/L

Start with 800 mL of distilled water to dissolve all salts. Adjust the pH to 7.4 with HCl. and add distilled water to a total volume of 1 liter.

Just to add: 

Taha mentioned correctly that the solution of 0.9% NaCl as used in Clinical Medicine has a tonicity of about 300 mosmol (which is approx.  the "physiological" tonicity of HUMAN blood). It is never used as a "physiological" buffer solution like PBS and others, which always are used (mostly - as said- in laboratory work) for achieving a sort of to meet (of cells, tissues, etc.) . Such always depend on the system one has to work with (acidic / basic) and -  finally - one tries to get also kind of a correct tonicity (= mosmol, hypo- as well as hypertonic solutions are used for certain purposes) depending also on the system to be tested or in work. This means that you can't use plain 0.9 % NaCl solution for use in experiments on culture /cell / organ systems which are different from the tonicity of the system to be checked. Regarding this, Gyanaranjan Dash is wrong in saying: "Any saline will do the job", but for sure right in saying: "yeast perhaps preferring acidic conditions".

BTW, I have checked several ampoules of "physiological saline (0.9% NaCl for clinical use)" and found (in most of the measured solutions) pH of 6.7 to 6.9 and a tonicity of around 285/289/290 mosmol (pH-meter and osmometer critically were adjusted prior to measurement).

Needless to say that I saw a lot of scientific articles stating in their section to have used "PBS [1x, 2x,10x, etc.) " but unfortunately not stating how their PBS was made / which composition the PBS had.

When working in Electron Microscopy you / one might have an idea on the difference between regularly and specifically "buffered" solutions in specimen preparation vs. use of only 0.9% "pyhsiological saline":

if you / one  - for example - store muscle biopsies from the operating theatre in 0.9% NaCl just to deliver it to the Lab for further processing [duration say 10-15 minutes only) you'll get huge & striking changes and alterations in ultrastructural morphology (i.e. vacuolization of some muscular compartments).

Regards, Wolfgang

A solution of a salt or salts that is essentially isotonic with tissue fluids or blood; especially : an approximately 0.9 percent solution of sodium chloride—called also normal saline solution, normal salt solution, physiological saline solution, physiological salt solution.

The most common composition of PBS (1X) pH- 7.4

4.3 mM Sodium Phosphate, Dibasic (Na2HPO4)

137 mM Sodium Chloride (NaCl)

2.7 mM Potassium Chloride (KCl)

1.4 mM Potassium Phosphate, Monobasic (KH2PO4)

There are many different ways to prepare PBS. Some formulations do not contain potassium, while others contain calcium or magnesium. But most common methods is as follow:

Start with 800 ml of distilled water:

Add 8 g of NaCl.

Add 0.2 g of KCl.

Add 1.44 g of Na2HPO4.

Add 0.24 g of KH2PO4.

Adjust the pH to 7.4 with HCl.

Add distilled water to a total volume of 1 liter and pH 7.4

Dispense the solution into aliquots and sterilize by autoclaving (20 min, 121°C, liquid cycle). Store at room temperature.

can anyone help me with recepie of "Phosphate buffer with 1.17%KCl" ??

Dear, Miss Deepthi Agarwal

what is molarity of the resultant PBS solution obtained from the conc. you mentioned. how to make 0.1 M PBS solution ?

@Mehwish Faheem: sorry if I am really late with this my answer:

If you go to Taha's Re #5 you'll find:

@ Senthilmurugan Murugaiyan:  [apologize for lengthiness - only for your convenience]

If you calculate only the  8g / 1000ml NaCl you'll arrive at approx. 0.1367M, which in terms of "usually" characterizing  "PBS"  would be consistent with PBS (10x)

(58.5 (58.44277)  g NaCl / Liter = 1.0 M 

5.8442770000065 g NaCl / Liter = 0.1 M

0.58442770000065 g NaCl / Liter = 0.01 M ) 

BUT:

The important [buffer] component is 1.44g of Na2HPO4 / 1000 ml which amounts to approximately 10mM - therefore as an accepted convention, the dissolution/ mixing of         

NaCl          8    g

KCl            0.2 g

Na2HPO4  1.44g

KH2PO4    0.24g    in 1000 ml of (DI) water in biochem. Lab-jargon definitely is designated  

PBS (1x) solution   and being termed as   '0.01M'.

There are really different opinions / views about how to define in the case of "PBS and MOLARITY or MOLALITY......  mix of different salts, buffer, etc.  ...

probably means the molality is 0.01 M, rather than the molarity. PBS contains about 10 g total salts (9.88 g to be exact) per liter of solution, giving it a molality of 0.01 M (citation cf.: https://www.quora.com/Why-is-the-molarity-of-PBS-1X-0-01M )

An interesting recipe (and explanation) I found in a 'chemical forum' [also questioned but not mentioned: effects on / of tonicity/osmotic pressure, etc.: see below] :

[Citation: ]  

I routinely run immunos in my lab.

Your 10X PBS recipe is a 0.1M PBS solution. For most immuno, for washes etc, you would use a 0.01 M (in other words 10 mM) 1X PBS solution which contains the following

1X PBS:

137   mM NaCl

   2.7 mM KCl

 10    mM Na2HPO4

   2   mM KH2PO4

therefore, 10X PBS STOCK solution would be:

1.37 M NaCl

   27 mM KCl

100 mM Na2HPO4

20 mM KH2PO4

You calculate this in the following manner:

For example 10X PBS

Given  MW NaCl 58.44, that is 58.44 g in 1 L = 1 M (58.44 g/L),

your desired molarity 1.37 M in 1 L

58.44 g/L x 1.37 M = 80 g in 1 L

Given MW KCl 74.55, desired molarity 27 mM (or in other words 0.027 M) in 1 L

74.55 g/l x 0.027 M = 2 g in 1 L

etc....

Hope this helps!      [End of citation]  = Re No 5 by rats79 @ [http://www.chemicalforums.com/index.php?topic=34228.0].   

Another - in that thread - following question, namely No. 7 by Phlogiston, has NOT been ANSWERED so far):

"Where do the desired molarities come from that you've listed - is it for the ionic strength, or perhaps the osmotic pressure of the solution?"

One - at least I - would be willing to accept that molarities/molalities of the 1xPBS would fit or at least are approximate to physiological parameters (right ionic strength of solution not to provoke osmotic shock or stress to cells).

cf. also: https://www.researchgate.net/post/Does_anyone_know_the_procedure_to_prepare_a_01M_solution_of_PBS2

Last but not least: cf. also:   https://en.wikipedia.org/wiki/Phosphate-buffered_saline :

"The pH of the 10x stock solution of PBS is ~6.8, but when diluted with water to 1x PBS it should change to 7.4. ....   ..... "

Best regards, good luck and good night...

my question is why both NaCl and KCl being added? Can NaCl alone be sufficient to prepare  PBS?

I think you should search on-line about basic cellular Na/K balance. The sodium potassium pump is a well understood example of an active transport mechanism. Sodium and potassium ions are pumped in opposite directions across a membrane building up a chemical and electrical gradient for each. These gradients can be used to drive other transport processes. 

The classical CSHL protocol for PBS calls for both Na and K ions. The phosphates set the pH to the physiological one.

http://cshprotocols.cshlp.org/content/2006/1/pdb.rec8247

The basic and dibasic phosphates salts may have various amounts of water associated with them. Check the exact composition of your phosphate salt, let the phosphates fully dissolve (e.g. the basic phosphate Na2HPO4 usually takes the longest to dissolve). Check the pH after all salts are dissolved. CHSL recommends to adjust pH with HCl, but, instead, I often get pH

PBS closely mimics pH, osmolarity and ion concentration of cells while saline solution lacks buffering capacity and has lower pH than cells. That makes PBS more adequate for washing cells, however, if a quick wash is required prior to tripzin for example you can use saline without problems. I wouldn’t use saline as a solution that is going to be in contact with cells for larger periods of time than a quick wash.

I guess you've already got the difference between the two. However, for oral gavage in mice, we always prefer PBS.