Reducing particle size can speed dissolution. A manufacturing step can also alter the way molecules pack in a solid, so a faster dissolution curve alone cannot show which change produced the result.
The investigators compared dry grinding, rapid expansion of a supercritical solution, and a polymer-containing composite for the experimental compound GML-3. After rapid expansion, they reported particles in the 20–40 nm range and a large increase in dissolution rate. They also reported signs of a change in crystal form.
Compare particle size, solid-state characterization, and dissolution under the same test conditions. When size and crystal form change together, the curve does not isolate the effect of either. The laboratory result also leaves open how much drug would be absorbed from a finished product.
Markeev and colleagues, Polymers (2023). Journal article · Full text.