Use of a solid fraction sensor to evaluate a solid fraction of a target pharmaceutical sample and solid fraction sensor

A method of evaluating a solid fraction of a target pharmaceutical sample by means of a solid fraction sensor, wherein the solid fraction sensor has a first conductor element, a second conductor element, an operation space and an energy source arranged to generate an electric field in the operation space by means of the first conductor element and the second conductor element, the method comprising:

• positioning the target pharmaceutical sample in the operation space of the solid fraction sensor;
• determining a capacitance between the first and second conductor elements with the target pharmaceutical sample located in the operation space;
• and
• converting the determined capacitance together with information about a composition of a reference pharmaceutical sample having essentially the same dielectric properties as the target pharmaceutical sample and about a thickness of the reference pharmaceutical sample into a solid fraction of the target pharmaceutical sample,
• wherein the information about the composition of the reference pharmaceutical sample comprises pairs of permittivity of the reference pharmaceutical sample and a corresponding solid fraction ratio of the reference pharmaceutical sample.