Introducing ReactALL’s in-situ pH probe

Controlling pH is a critical factor in process chemistry because it directly influences the success of reactions, the quality of intermediates, and the stability of final drug products. Reaction rates often depend on pH, since protonation states determine whether a transformation proceeds quickly or slowly, and this in turn affects overall yield. Beyond kinetics, pH also governs selectivity: certain side reactions can be suppressed by carefully choosing acidic or basic conditions, ensuring that the desired product pathway dominates. Stability is another key concern, as many intermediates and active pharmaceutical ingredients degrade rapidly under extreme pH, leading to unwanted by-products or loss of potency.

Monitoring and controlling pH is essential during reaction screening, as it significantly impacts experimental outcomes. The new ReactALL pH Probe enables real-time, in-situ pH measurement throughout an experiment, ensuring optimal control and reproducibility.

The new ReactALL pH probe features a buffered gel reference at the sensor tip and measures pH by drawing up the sampling shaft, wetting the sensor for a rapid response within seconds. It includes an automatic wash cycle to maintain cleanliness and accuracy between measurements. Using pulsed measurement technology, it is possible to take a measurement every 20 seconds.

The probe is made from PEEK, a high chemical resistance plastic replacing the traditional thin fragile glass of common pH probe, making it more robust and much less likely to break, despite being only 3 mm in diameter. Additionally, because of its thin diameter, it is directly integrated into the SmartCap system, allowing for in-situ measurements. The probe supports multi-point custom calibration with user-defined buffers. There is wireless communication between the probe and the software, making it compatible with further automation and robotics, allowing up to 5 probes running in parallel.

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