I had prepared my nanoparticles by ultrasonic degradation of the polysaccharide. DLS studies showed that the PdI was 0.2. Now how can I conclude that what is the number of nanoparticles present in the solution like whether they are 10,000 or 100,000?
For metal nanoparticles, you can estimate the number of nanoparticles through a simple calculation. you need to know the size and the number of the atoms in average nanoparticles. Here You can apply similar calculation. based on nanoparticle size you should estimate the number of polymer chains in average nanoparticle and through initial polymer concentration, you can make a rough estimation.
The PDI is only a measure of the width of the distribution. What is the z-average size?
Mr. Rawle the z-avg is 199nm with 92% of particle population as evident from the peak are having the diameter of 150.8 nm.
The above particle size was from a 1 ml reaction. I am curious to know what amount of nanoparticles are present in say 100 microliters of the solution.
Mr. Rawle, I think as I told you earlier that my total volume of sample (nanoparticles) is 1 ml. It may be asked by anyone that what is the nanoparticle (%) or amount of nanoparticles that are present in a specific volume of the aforesaid sample. because I guess DLS (Malvern Zetasizer) illustrates the particle size of a solution and if I use say 100 microlitres from the already characterized sample then it needs to be further diluted and in that case, I guess I won't be able to predict the specific quantity of nanoparticle in 100 microliter solution.
Kindly correct me if I am conceptually wrong or anything of that sort you think?
The nanoparticle concentration can be expressed in molar proportions, volume or mass proportions. This can be measured or estimated in a number of ways. For number count use a technique like NTA or RMM to count and size particles in the nano region.
The particle size distribution is the distribution - it doesn't matter whether it's in 1 mL or 1 tonne. DLS measures a size distribution, not the concentration. At the sizes you mention (~ 200 nm) you could use laser diffraction and this gives you a Bouguer's Law (often called Beer-Lambert) estimation of the concentration.
Thanks, Mr. Rawle for your precious comments & thanks are also due to Parisa & S.M. Amini
Thanks everyone
Finally what technique you have measured thenanoparticle concentration ?
Nanoparticle tracking analysis will give an idea about the number of particles before and after analysis
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