Wireless glass-free pH measurement.

pH is a critical parameter in a multitude of areas, including research, agriculture, water environment, food, industry and more. Sentron has developed a comprehensive line of wireless glass-free probes for pH measurements on your own phone or tablet. Sentron’s glass-free ISFET pH sensor technology offers accurate and reliable pH measurements for demanding applications.

Glass free pH measurement

pH is a critical parameter in a multitude of areas, including research, agriculture, water environment, food, industry and more. Sentron has developed a comprehensive line of wireless high quality probes for glass-free pH measurements. Sentron’s ISFET pH sensor technology offers accurate and reliable pH measurements for demanding applications.


Whether you run a large-scale laboratory or whether you are in a classroom, the safety and integrity of your studies and instrumentation is of the utmost importance. The Sentron laboratory glass-free ISFET pH probe delivers precision while offering simplicity and versatility.
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Agriculture varies from the home gardener to horticulture with commercial greenhouses. They all have a common thread: they sustain the world. Testing, monitoring and adjusting growth parameters help to maximize efficiency, quality and production. The Sentron glass-free ISFET pH probes are a good solution for this. 
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In many industries, pH is a critical parameter. These industries include food (e.g. meat, dairy beverage, wine and beer), pharmacy, textile and water treatment. pH testing during the manufacturing process can enhance production usability, accuracy and excellence.
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Take the lab with you. Our wireless handheld pH probe with glass-free ISFET pH technology makes it ideal for measuring the pH of water in tougher settings. Take direct pH and temperature measurements for water quality monitoring using your smartphone or tablet.
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Durable, accurate, wireless

Wireless and durably interchangeable, our premium pH probe enables you to monitor this essential parameter in whatever application, whenever you want and wherever you are.

Sentron app
Wireless Bluetooth pH measurement on your own phone or tablet. Sentron provides the free app, as well as dedicated Samsung phones and tablets.
Sentron app
Cloud-based free application for setting configurations, calibrating, acquiring, visualizing, storing and exporting all your measurement data.
Sentron app
Unlimited number of connected probes for simultaneous wireless pH measurements.
Sentron app
Need for simultaneous multiparameter measurements? Follow us! Soon we will release our innovative multi-sensor probe, connectable to the Sentron App for multiple parameter measurements and visualization.
Sentron app
Intuitive app that guides you through calibration and measurement settings.

Complete control from the Sentron app.

What’s next?

By taking a serious look at all applications, we keep entering into new innovations in our semiconductor production facility. Soon we will launch sensors for EC and ORP, with which great multisensor solutions for e.g. water monitoring can be provided. Additionally, we  continue our R&D on ion-selective sensors.

For all applications we constantly seek innovations in our semiconductor factory. Soon we will launch sensors for EC and ORP. These can provide great multi-sensor solutions for, e.g., water monitoring. Imagine: all parameters to be monitored using one and the same probe! Additionally, we’re looking forward to finalize the R&D on ion-selective sensors.

The EC is the measure of a material’s ability to allow the transport of an electric charge. This knowledge is important for water-quality monitoring in public water supplies, in hospitals, in boiler water and in industries which depend on water quality such as horticulture and breweries.

Low conductivities are expected for pure water applications like aquaria, household, drinking water and rivers. On the other side, high conductivities are expected for industries like irrigation and greenhouses. 

The ORP is the measure of the tendency of aqueous solutions, or any other chemical species, to either acquire electrons from an electrode and be reduced thereby, or to lose electrons to an electrode and be oxidized thereby. This knowledge is important for water-quality monitoring in aquaria, swimming pools, as well as environmental and wastewater sampling. E.g. ORP is an indicator of micro-organism inactivation in a swimming pool or spa pool.

High ORP values (positive potentials) are expected for aerated surface water, rivers, lakes, oceans and rainwater. Low ORP values (negative potentials) are expected in places with limitations in air supply such as submerged soils, swamps and marine sediments.

Sentron is working on innovative developments on ion-selective sensors that have a membrane mixture suitable for detection of different ions based on the ISFET technology. Selectivity is based on proprietary modifications with several polymer matrix configurations. Nitrate (NO3), Ammonium (NH4+) and Potassium (K+) are currently in development.

It’s all about sensors

Besides the wireless and durable pH probe product line, you can also reach out to us for any customized sensor integration into your own product.

The non-glass ISFET (Ion Sensitive Field Effect Transistor) pH sensor is one of the sensors that we produce in our semiconductor production facility. It is robust and does not require wet storage. This makes it well suited for, e.g., agriculture, water environment, food and other industrial applications. Our ISFET assemblies are used successfully in the market of FDA approved and CE certificated medical devices for the medical application in gastro-enterology.
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Contract development

In our facility we also produce the advanced miniature piezo resistive sensor that is equipped with a full Wheatstone bridge for differential pressure measurements: thus, no influence due to atmospheric changes. The narrow dimensions of this pressure sensor make it ideally suited for medical applications. Our pressure sensor assemblies are already on the market in medical devices for cardiology, as well as for neurology and urology catheters.

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Contract development

Frequently Asked Questions

Sentron Europe does manufacture sensors in her semiconductor production facility in Leek, The Netherlands. These are small sensors of just 1 to 3 millimeters or less. The sensors are used in the sensor integration services that are offered to OEM customers. Together with these partners we develop and produce OEM sensor products to a variety of markets: medical, agriculture, water, food, or else. Besides these OEM products, Sentron manufactures standard probes as well. These are available in the web shop.

In our semiconductor production facility we also produce the advanced miniature piezo resistive pressure sensor. This sensor is created using Sentron’s proprietary full Wheatstone bridge for differential pressure measurements. Thanks to this differential pressure measurement atmospheric changes have no effect. The sensor is stable with low drift in varying pressure and temperature environments. See the page sensor integration services for more information.

Moreover we are working on the manufacture of the EC sensor for electrical conductivity. More information will follow soon.

The differential pressure sensor with full Wheatstone bridge, the ISFET sensor and the EC sensor are all very small. The largest is 3 mm in length, but most are much smaller than that. They are used for example in medical catheters for cardiology or urology where size does matter.

The current probes in our web shop are equipped with the ISFET pH sensor. Additionally they have an integrated temperature sensor. Soon we will release the multiparameter sensor part with the ISFET pH and temperature, as well as the EC sensor for electrical conductivity. Later on the ORP sensor is included as well in these multiparameter sensor probes. It is to measure the oxidative reduction potential. All these parameters are read out by the same Sentron app.

Thanks to the technology the ISFET pH sensors are robust and can be stored dry. This has a great benefit for applications like water quality measurements in stream beds and tidal areas, where the water level changes in time and the probe will occasionally be above the water level.

Another advantage of is the response rate of ISFET pH sensors. It is faster than glass bulb pH sensors, thus providing faster measurements and enabling better process control.

Moreover, the glass-free approach makes the pH also available for inline food processes and medical applications like gastro-enterology, for which any glass splinter could be fatal.

The ISFET pH sensor is sensitive to direct sunlight, so the best applications for the ISFET pH sensor are in the soil, in water tubing systems, in food, in medical applications like the gastro-intestinal tract, etc.

The wireless product line has connection with the mobile device via Bluetooth. No cable is used. No limitation of just 1 probe per meter. No  maximum of 1.5 meters distance anymore. In other words, the wireless probe enables more flexibility and use cases than the wired probes.  

The Sentron app is free and can be installed at any mobile device (Bluetooth 5.0), including your own. Multiple probes can be connected at the same mobile device and read out simultaneously. Moreover the smartphone features are used for the datalogging, like GPS location, and export functions are simple, like social media, cloud use, etc.

Where conventional pH meters are hard to understand, the Sentron app is very intuitive. It guides you through all required steps like the calibration. With animations it shows you exactly what to do at which points. Please judge yourself: it is available for iOS and Android in the AppStore and PlayStore!

You can purchase the probes at our web shop. Per product a description is provided, as well as suggestions for products to add to your cart.

Yes, the pH probes do make use of the automatic temperature compensation. ATC improves accuracy and keeps the electrode in calibration regardless of the temperature.

During pH calibration, ATC reads the true temperature of the buffer and assigns the exact correct value. During sample or interval measurements, ATC reads the true temperature of the sample and adjusts the slope to remain in collaboration.

Let’s get connected and see whether we have a match. Please refer to info@sentron.nl and we’ll contact you as soon as possible.

Besides the standard product-line, we also provide contract development and contract manufacturing of sensor assemblies. More information on our OEM services can be found at Sensor Integration Services.

We would love to hear more about your product development. Together we will discuss whether our sensor integration service would be suitable for your product. Please refer to info@sentron.nl and we’ll contact you as soon as possible.

While the SI400 and SI600 pH meters themselves are out of stock, the wired probes for these meters can still be purchased at our webshop. However, we strongly suggest to take a look at the new, wireless, product line as it has several benefits and great features compared to the cabled pH product line.

At our support page you might find your answer to more specific probe related questions. If not, please do not hesitate to refer to info@sentron.nl for personal contact.