pH Robust Screw Cap Probe


  • For pH measurements between pH 7.0-9.0
  • Robust fiber with threaded tip
  • Exchangeable Sensor Screw Caps
  • Minimal cross-sensitivity to high ionic strength
  • With underwater SUB-connector (-SUB)

This robust pH screw cap probe represents a new generation of fiber-based pH sensors from PyroScience and a viable alternative to traditional pH electrodes. This new sensor format is composed of a robust cap adapter fiber with stainless-steel tip (10cm length, ø4mm) and a disposable plastic screw cap with integrated pH sensor. The pH sensor cap can be screwed on the threaded tip of the robust fiber. If worn out, keep the fiber and simply exchange the pH sensor cap and continue with your pH measurements. The PHROBSC-PK8-SUB comes initially with 4 sensor caps. If more caps are required, an additional set of 4 pH sensor screw caps (PHSC-PK8) can be obtained. 

With this new sensor format, PyroScience aims to provide a more sustainable approach (reducing waste) and improve even further the user-friendliness of our sensors.

pH range 7.0-9.0 This sensor is specified for the pH range 7.0-9.0. For detailed specifications, see the respective pdf file in the Downloads tab.

Screw cap probe. For easy and sustainable renewing of the sensor after demanding applications. Replacement screw caps can be found under accessories. Tip diameter 4mm.

Optical isolation.This sensor type is equipped with an additional optical isolation protection layer. This layer reduces enhanced sensor aging and interference with the measurements in applications at high ambient light (e.g. direct sunlight, illuminated samples) and in fluorescing / light-sensitive samples.

Easy calibration. Calibration of the pH sensors is performed at pH 2 and pH 11 using our easy-to-use calibration capsules (PHCAL2 and PHCAL11). For detailed calibration recommendations, please refer to the manual in the downloads tab.

SUB-connector (-SUB). Underwater sensor connector (instead of standard ST-connector) needed for applications with underwater devices.

Applications. To get an overview of potential applications and to see our sensors in action, please visit our Applications site!

Price List

Calibration Capsules (pH 2)


For obligatory acid calibration of optical pH sensors. Each capsule results in 100mL calibration solution (PU=10).

Calibration Buffer Capsules (pH 11)


For recommended basic calibration of optical pH sensors. Each capsule results in 100mL calibration buffer solution (PU=10).

Additional Sensor Screw Caps


Additional sensor screw caps for simple exchange of the pH sensitive sensor (PU = 4 pieces).

Every PyroScience pH meter with a SUB-connector (underwater devices) is compatible to this sensor. Use this link to get a list of all compatible meters. Select additional requirements to find the optimal meter for you and your application!


Exemplary Setup


Choose the one channel underwater AquapHOX logger (APHOX-LX) with the robust pH probe PHROBSC-PK8-SUB with underwater connector.

Exemplary Setup


This set-up includes:

  • PICO-PH-SUB with USB cable
  • pH sensor for pH range 7.0 - 9.0
  • Necessary accessories

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