Dear Elmira,

The Raman spectra of diamond is very strong. Just look for 1332 cm-1 line in your material. Possible you have to measure several points to find diamond particle.

Best regards, Alexander

Hi Elmira,

If the diamond particles in your emulsion are below 10nm you will find Raman difficult anyway. 

If you know that the only possible particles in the emulsion are diamond you can use dynamic light scattering (DLS) to determine their size and presence.  The technique is done without drying and will measure particle sizes between 10um and 0.3nm.

The DLS technique can also be used to measure the potential of the double layer around the diamond particles, which can be useful for determine if a certain emulsion will be stable.

Hope this helps, Nik.

Dear Elmira,

one more remark: You don´t have to dry the samples for Raman. Raman spectroscopy also works  in slurrys or liquids - water is not hampering the acquisition. If other solvents are used, you might check for overlapping bands (however despite the broader D band of carbon I cannot think of other vibrations that might overlap). Additionally the very narrow band width in combination with the high intensity of the diamond line make the detection easy, despite (broader) underlying bands. I was able to detect intense signatures of diamond in most of my ore samples, just because they were cut with a diamond saw blade despite strong underlying fluorescence.

Regards

Marek