Nanoparticles
The Nicomp® DLS system effectively measures nanoparticle sizes both online in the process environment and in the lab.
The typical definition of a nanoparticle is a particle with a size between 1-100 nm. The term has been defined this way in both ISO standard 27687 and ASTM standard 2456-06. In the EU the definition is more clouded because of the wording used concerning that about 50% of the number distribution should be between 1-100 nm. Dynamic light scattering (DLS) remains the most popular particle size analysis technique for nanoparticles. The Nicomp® DLS system is used in many industries to measure the size of nanoparticles, both in the lab and online in the process environment.
Featured White Paper
Featured White Paper
Featured White Paper
Online Nanoparticle Size Analysis
Many nanoparticle production operations could be monitored continuously using the Nicomp N3000 online DLS system.
Nanomedicine research has grown quickly during the past few decades with much of the focus placed on drug delivery. Nanoparticles provide benefits such as reducing toxicity and side effects. Controlling the size of these nanoparticles is critical. While the majority of the particle size measurements of this product is in the lab, it is now possible to make these measurements online (or at-line) in the manufacturing environment.
The Nicomp N3000 online system has been installed in several customer manufacturing operations that track particle size during production runs. The online system removes a sample from the process, dilutes the sample to avoid multiple scattering effects, measures the sample, and then repeats the procedure. The complete measurement cycle is approximately 2 minutes, providing continuous particle size information to the process engineers monitoring the manufacturing operation.
The Nicomp N3000 online DLS system was installed downstream of a high-pressure homogenizer at BIND Therapeutics in Cambrdge, MA and set up such that it can grab an emulsion sample from the process stream every ~2 minutes. The relationship between the particle size (left y-axis) and homogenizer pressure (right y-axis) was established.
The next experiment had initial size readings ~ 5-7 nm under the target size and hence a pressure adjustment was made (1,000 psig decrease). At later time-points, as expected, the mean particle size increased by ~ 5-10 nm:
Sizing Extremely Small Particles
Dynamic Light Scattering is the only optical particle sizing technique that can reliably size particles below 10 nanometers.
DLS is a standard, time tested method for sizing dispersions of nanoparticles. It is the only optical particle sizing technique that can reliably size particles below 10 nanometers.
Figure A illustrates this capability. The PSD in this figure is from a commercial Buckminster Fullerenes (C60) or Bucky-Ball suspension. C60 has a reported size in the literature of 14 Angstroms or 1.4 nanometers. The PSD consists of single peak that has a mean diameter of 1.3 nm, very close to the expected value. As a further demonstration of the unique capabilities of DLS,
Figure B contains a PSD from a different lot of the same C60. Notice the presence of a second peak at 200 nm. This peak is likely from amorphous carbon contamination from the synthesis process. DLS was able to sort out the primary peak at the correct size as well as detect the contamination peak.
Figure A
Figure B