Dear Łukasz Hanusek;

Ag NPs can be dispersed easily in toluene and xylene, more details in the reference;

https://smtnet.com/library/files/upload/Metal-based-Inkjet-Inks-for-Printed-Electronics.pdf

if Ag *nanoparticles* in an organic solvent, it's not a "solution" but a dispersion

It is possible to ablate bulk material using a laser (1064 / 532) in the solvent to create suspensions directly in the solvent. I know this has been done in methanol and ethanol with an eye to creating fuel additives to change combustion dynamics and to allow their addition to plastics and paints etc. I think you could try other solvents on a case-by-case basis. You have to set the ablation equipment up to contain a spill in case the laser generated ultrasound cracks something, and you have to rigorously exclude air and oxygen to remove the fire hazard, but it's chemical-free and otherwise pretty simple. https://triermain.com/agtech/. Hope this helps. John

Artur Braun Your tongue-in-cheek response is appreciated and in line with many RG questions that suddenly have a different question inserted sometimes to do with the original question and sometimes not.

Łukasz Hanusek (From Wikipedia): 'Silver nitrate is highly soluble in water but is poorly soluble in most organic solvents, except acetonitrile (111.8 g/100 g, 25°C)'. OK, so that tells me that you can dissolve AgNO3 in acetonitrile perhaps with some addition of ammonia to form the Ag(NH3)2+ complex (usually the favored precursor in aqueous environments). Reduction could take place with H2 or perhaps with dilute (5 or 10%) hydrazine hydrate, diluter concentrations favoring smaller sized material. The relatively high density of Ag will mean that only really small material can stay in suspension (carry out a Stokes' law calculation). In the presence of air or oxygen the top surface of the 'silver' particles will actually be in the +1 oxidation state, i.e. Ag2O and it's this ion that's the active bactericide

Here's a couple of webinars to watch for generalities (Reg E Stration required):

Silver colloids and invisible ink

https://www.malvernpanalytical.com/en/learn/events-and-training/webinars/W150902SilverColloidInvisibleInk.html

Metal colloids - their preparation, application and characterization

https://www.malvernpanalytical.com/en/learn/events-and-training/webinars/W160218MetalColloids.html

I need method of preparing silver nanoparticles using sodium borohydride as reducing agent