The presence of particles several standard deviations from the core populations of particles significantly influences the performance of inkjet inks and the stability of emulsions. The safety of emulsion-based drugs having 300 nm of mean diameters can be influenced by particles > 5 microns, particles with the mean diameter of over 10 times.
Laser Diffraction as well as other particle sizing techniques do not have the sensitivity to identify small safety hazards. The USP-729 addresses this problem with the condition that emulsion-based drugs have to be assessed with Light Obscuration or SPOS.
Since oil emulsions and other industrial dispersions are highly concentrated, they pose challenges to the particle size analysis. They need considerable dilution before using particle sizing techniques. The Accusizer 780 APS dilution system from Entegris solves this problem by using a unique two-stage dilution system. It can set dilution factors from 10 to 144,000 in real time to house samples that change with time or that change from lot-to-lot.
The main features of the Accusizer 780 APS dilution system are:
- Incorporates two-stage dilution system
- Fits well with high-volume QC laboratories due to the automation
- Can be utilized as a formulation development tool to verify temperature or time stability
- Monitors large particles in a dispersion undergoing change.