USP <786>, Particle Size Distribution Estimation by Analytical Sieving
The sample is sieved by using three or four stacked sieves of different size. The distribution of the fineness in the sample is determined by the percentage of the sample that passes through each size of the sieve.
USP <831>, Refractive Index, USP <841>, Specific Gravity, and USP <781>, Specific Rotation
These three tests are physical property tests used to verify the purity of each ingredient based on the USP specifications.
USP <911>, Viscosity by Kinematic and Rotational Processes
This method uses USP <911>, to measure the thickness of liquid by measuring the speed of the flow time of the liquid through a capillary tube as kinematic viscosity, or by rotating the liquid in a viscometer.