What do u mean? 

I couldn't understand you.

I have NaNO3 salt how can I convert it to nanoparticles salt , is by dissolving it in water Consider nanoparticles or not

thanks for your interesting

1. first of all, nanoparticles have to be particles ( solid). NaNO3 is a soluble salt which is not solid in the solution/water 

2. NaNO3 dissolves in the water and become free Na+ and NO3- ions, they are much smaller in size than nanoparticles.

3.in order to make  soluble "ions"  into nanoparticles, you may want to "dope" or"adsob" the ions (NO3) onto nanoparticles.

Dea hiader

greetings

one method maybe by precipitation from the saturated solution under high agitation and slowly gradient of temperature.

thanks very much Ali for your help

Ruiqiang Liu     You raise an interesting point.  When do we have a particle and when do we have a solution? (Incidentally the material need not be solid to be a 'particle' - could be a liquid or a gas).  With the definition of nanoparticle being something in the 1 - 100 nm range (ISO and ASTM) then it's clear (at least to me) that the sodium ion radius at 0.227 pm (diameter = 0.46 nm) wouldn't be considered nano.  However, the system still provides a heterogeneity/boundary and thus (for example) scatters radiation.  Indeed we could ask about the blue sky (caused by (Rayleigh/Tyndall) scattering of the molecules in the air.  However, let's consider a fully soluble biomolecule or polymer.  This can be several nm in size.  These scatter light and show a defined boundary.  They can be independent, discrete, and possess individual transport properties.They are to all intents and purposes 'nanoparticles' even though in solution.  Anyone else with thoughts on this conundrum?.

Thanks Dr. Rawle for your comments, which I am really happy to read. let me do another definition: 

1. I think it is not reasonable to discuss "nanoparticles" in a "Homogeneous system", such as the case of 1 mM NaNO3 solution. Even though I spectate that  a sodium ion (Na+) and the loosely bound water molecules may be in nanosized range in the solution. theoretically I still do not think a fully soluble biomolecule or polymer solution is a nanopartcile-containing system. 

2. thus it is more rational to discuss "nano particles" in a "heterogeneous system" so the NaNO3 solution is not a nano particle system but the small NaNO3 crystals floating in the air may be nanoparticles

Hi Ruiqiang Liu   I have little problem with material dissociating into ions in solution and your 2 examples of NaNO3 are fine with me  What is interesting is the split between the bioscience people (who consider radii and solutions) and physicists (who consider diameters and heterogeneities).  Molecules scatter light in an identical (at least to the equations..) manner to particles.  From this perspective, there's no difference.  And when the sizes of the dissolved phase gets to tens of nanometers then the difference between particle and solution appears fuzzy (deliberate oxymoron!).  Maybe it's simply a matter of terminology.