usePAT (ultrasound enhanced Process Analytical Technologies) uses ultrasonic fields for the improvement of in-line process monitoring applications. Radiation forces in the ultrasonic standing-wave field (see Figure 1) allow us the spatial manipulation of small particles dispersed in liquid media. This is done in a gentle way, without any negative impact on either of the components of the suspension. Such particles can be of different nature (e.g. cells, bacteria, microplastic, crystals, oil droplets, air bubbles, etc.). The extent of the applied force depends on the particle size (1-150 µm) as well as the ratio of speed of sound and mass density of solid matter and liquid, respectively. The accurate control of particles in a process stream can contribute to the process control in different and specific ways without any need of interference or maintenance. 

Our technology offers various benefits to our clients, depending on the device used (soniccatch, sonicwipe or sonicclean). Regardless which one of our products is applied, the outcome is similar in that it results in an enhanced stability, sensitivity and selectivity of the various industrial and analytical sensing devices applied to.

For a better steering and control of a specific process, desired particles can be caught in certain regions of the sound field via soniccatch, thus forming small agglomerates of concentrated particles (see Figure 2).

These can serve as in-line samples for the sensor coupled to our product and thereby enable reliable real-time measurements to take place. The resulting signal quality (SNR, LOD, etc.) generated from these agglomerates resembles that of measurements done on sediments. This was proven during numerous instances (e.g. the coupling of soniccatch with a midIR ATR - or a RAMAN- probe in order to supervise a fermentation process, etc.), some of which can be found mentioned in more detail on our website.

In case the aim is related to cleaning and further upkeep of a specific sensor without interrupting its function or the process it is applied in, this can be done via the generation of an ultrasound field by sonicwipe or sonicclean that will remove contaminations adhered to the surface of a sensor.

When an ultrasound field is generated by soniccatch (e.g. see Figure 3), the data gathered is highly detailed and specific and can provide the client with reliable information for particles ranging from 1-150µm in size at concentrations as low as 0.001g/L. Notable to mention is also the fact, that with the concentration of the particles in the nodal regions of the ultrasound field, the liquid surrounding them can be analyzed separately as well. This aspect is for example especially convenient when supervising continuous biological processes (e.g. fermentation, biomass production, etc.).  

Figure 3: (Left) Particles caught in the ultrasound field generated via soniccatch, coupled to a Raman sensor, during a measurement. (Right) The difference in the Raman spectra when the ultrasound is active or not for suspensions consisting of water and Polyvinyl Chloride Particles (Top) or S. cerevisiae (Bottom).

Further examples where the adoption of our technology proved possible and highly beneficial include:

• Coupling with a midIR ATR absorption probe while supervising a biological process in a pilot scale bioreactor.
• Supervision of a crystallization process in a crystallizer while attached to a Raman spectroscopy probe.
• Removal of gas bubbles in a medium capacitating high-precision liquid measurement.
• Detection of rare particles of interest in a medical environment suspension.
• Maintenance of optical particle size analyzer by keeping particles away from sticking to the sensor surfaces.
• Successful application in a wet lab to remove calcification and sugar-gel levels from pH electrode, upkeep of O2 probes regarding cleanness (wastewater industry), clearing the measurement slit of an NIR probe, etc.
• …

As stated earlier our products offer undeniable benefits regarding the improvement of the selectivity, sensitivity and stability of the analytical devices coupled to. Another advantage accompanying our products is their easy and simple way of implementation. They represent add-ons, compatible with a variety of sensors and can be personalised to a clients’ needs. Furthermore, our products are safe to apply since they are composed of materials that are in line with FDA guidelines, meaning they are:

• biocompatible
• autoclavable
• caustic-safe
• require little space
• easy to (un)assemble
• very compact and stable

By enabling/improving the retrieval of highly reliable in-line real-time data, our products can facilitate the implementation of processes such as PAT (Process Analytical Technology), a vital component of the QbD (Quality by Design) approach.

PAT (Process Analytical Technology) represents an approach to design, analyze and control manufacturing processes through the measurement of specific critical parameters and is seen as an important element of the QbD (Quality by Design) concept. Its execution is dependent on the usage of reliable real-time analytical data in a continuous manner throughout the production process, ensuring a higher yield and better quality of the final product, while at the same time cutting down on waste as well as the amount of raw material initially required!

The implementation of such an innovative and highly requested system is supported and pushed forward by the FDA (Food and Drug Administration) and the European Medical Association (EMA). This indicates that in the near future PAT will be a requirement for any production field, especially the food and health industry. This won’t be an easy task to accomplish and we at usePAT have dedicated our work into making that transition for our customers faster, safer and easier!