The ESP (Effusivity Sensor Package) is the first version of Mathis' technology that can be used to monitor powder mixing at the plant level. Earlier generations of the system were suitable for use in formulation and R&D settings, but suffered from one key drawback. The blender used to process the material had to be stopped to allow the sensor to do its work. Now, the wireless version can reside in the blender, taking effusivity measurements as the process takes place.
Effusivity is a series of measurements - including thermal conductivity, density and the heat capacity of a substance - that can be used to monitor whether powders have been mixed into a uniform blend. Put simply, the sensor detects materials in the same way that your hand can detect that metal feels colder than wood, even if they are at the same temperature. And like your hand, the system is rapid and non-destructive.
Mathis has shown that this principle can be applied to pharmaceutical processing. For example, when magnesium stearate (a lubricant) is used to coat particles in blending, it causes the density of the granulation blend to increase and the heat to transfer more readily. This is measured through the increase in effusivity after the lubricant is added.
The system's online functioning conforms closely to the principles of the US Food and Drug Administration's process analytical technology (PAT) guidance, which is seeking to encourage companies to make more use of in-process measurements to improve quality, boost yields and reduce wastage.
The ESP was 30 months in development, as Mathis developed the algorithms that would allow the synchronisation of the sensor reading with the time that the powder is in contact with the powder in the blender. The company recently signed an agreement with fellow US firm Brock Solutions for the commercialisation of the industrial-scale effusivity packages.
"Brock has been providing integration packages to many industries, including pharmaceutical … for 20 years. They know how to pull the parts together and that is key for the success of our technology as it migrates to manufacturing use within pharma," said Nancy Mathis, president and CEO at Mathis.
Next month, Mathis is holding a workshop at the Natoli Technical Training Centre in St Louis, Missouri, to demonstrate how to predictively determine the quality of tablets by monitoring lubrication in real time with its PAT tools. The two-day event will provide attendees with a general overview of how to reduce lengthy setup time of the tablet press, avoid wasted product and diminish failed dissolution tests.