Non-Invasive Optical Oxygen Sensors

Robust & real conditions: Look into any transparent vessel

Illustration: Measurement Method with Non-Invasive O2 Sensors
  • Glassware & disposables
  • Bags & single-use bioreactors
  • PET & glass bottles

The non-invasive optical oxygen sensors measure the partial pressure of both dissolved and gaseous oxygen. These sensor spots are used for glassware and disposables. The optical oxygen sensors are fixed on the inner surface of the glass or transparent plastic material. The oxygen concentration can therefore be measured in a non-invasive and non-destructive manner from outside, through the wall of the vessel. Different coatings for different concentration ranges are available.


  • Non-invasive & non-destructive online measurement
  • Measurement range from 1 ppb up to 45 ppm dissolved oxygen
  • Ultra low gaseous oxygen measurement down to 0.5 ppm
  • No consumption of oxygen
  • Signal independent of flow velocity
  • Measures oxygen in liquids as well as in gas phase
  • Autoclavable (SIP: 130 °C / 266°F, 2 atm steam sterilization) & CIP (Cleaning in place)

Selected Probes

Sensor Spots O2

Sensor Spots O2 - for normal measurement range and trace oxygen

Sensor spots (SP) are the most versatile version of non-invasive optical oxygen sensors. They are attached to the inner surface of any transparent vessel.

Examples are

  • Cultivation bags
  • Spinners
  • Glass reactors

The transmitter with its optical fiber can be fixed opposite the sensor spot by using our accessories (see accessories brochure) which can be adapted for nearly all kinds of vessels.

Flow-Through Cell O2

Re-Usable Flow-Through Cell O2

The flow-through oxygen minisensor (FTC) is a miniaturized chemical optical sensor integrated in a  flow-through cell. It is connected to the transmitter by an optical fiber. A glass tube with an inner diameter of 2 mm is coated with an optical oxygen sensor at its inner wall. The volume for liquid inside the FTC is about 100 (±10) microliter. The standard flow-through cell can be easily connected via Luer-Lock adapters to external tubings.

SensorVial & Vial Adapter

20 mL SensorVials with integrated chemical optical oxygen sensor & Vial Adapter

The SensorVial is a 20 mL glass vial with an integrated optical oxygen sensor stripe. It is connected to the transmitter by an optical fiber. The Vial Adapter holds the fiber in place and is adjustable in different heights. 2 different versions of the SensorVial are available: For stirred application the sensor stripe does not reach all the way to the vial bottom, while for non-stirred application the sensor stripe covers the whole vial side.

Examples for Applications

Non-Invasive O2 Sensor in Culture Bag
Pharma Industry: Oxygen Monitoring in Bags

Bags and single-use bioreactors are in the process of revolutionizing the way biopharmaceuticals are manufactured. Our non-invasive oxygen sensors are the tools to make the cultivation vessels fully disposable. As non-invasive pH sensors are also available, the two key parameters oxygen and pH can be controlled online.

Permeation Measurement with Non-Invasive O2 Sensor
Food & Beverage: Oxygen Permeation Measurement in PET Bottles

Non-invasive oxygen sensors measure both in liquid and in gaseous (headspace) phases. They perform through transparent materials up to a thickness of 10 mm and even through slightly opaque packaging. The measurement is carried out by firmly holding the fiber optic probe against the side of a PET bottle where the sensor spot is positioned. Adjustable mountings and bespoke fixtures are available. This system allows even the parallel measurement of different bottles as the fiber can be moved from bottle to bottle.

Bioprocess Development: Oxygen Monitoring in Shake Flasks

O2 supply is one of the major issues in the cultivation of aerobic organisms. Shake flask cultures are widely applied in academic and industrial bioprocess development. As adequate methods for real monitoring of dissolved oxygen were missing, sufficient O2 supply is usually assumed. The non-invasive oxygen sensors in shake flasks now ensure oxygen supply and give new insights into metabolic activity.

Respiration & Photosynthesis: Oxygen Monitoring in Glass Vials

Determination of respiratory activity is often performed for water organisms such as invertebrates, larval stages or eggs, but also for bacteria, cell cultures, yeasts or fungi. For algae measurement of photosynthetic activity is of great interest. Using our 20 mL SensorVial with an integrated sensor stripe oxygen can be measured simultaneously in the liquid sample and in the headspace. Autoclavable SensorVials for stirred and non-stirred applications are available.

Technical Data

Please click to enlarge.

Transmitters & Accessories

Fibox 4 Fiber Optic Oxygen Meter

Fibox 4 /
Fibox 4 trace

Stand-alone fiber optic oxygen transmitter

Microx 4 trace fiber optic oxygen meter

Microx 4 /
Microx 4 trace

Stand-alone fiber optic oxygen transmitter

OXY-4 mini - Multi-Channel Fiber Optic Oxygen Meter

OXY-4 mini/
OXY-4 trace

4-channel fiber optic oxygen transmitter

OXY-10 mini - Multi-Channel Fiber Optic Oxygen Meter

OXY-10 mini/
OXY-10 trace

10-channel fiber optic oxygen transmitter

Fibox 3 LCD trace - Fiber Optic Trace Oxygen Meter

Fibox 3 LCD trace

Fiber optic oxygen transmitter with LCD display

LP-1 Control Panel

LP-1 Control Panel

The control panel is a device for controlling single-channel oxygen transmitters.

Respirometer Chamber

Respirometer Chambers

O2 consumption measurements in aquatic organisms and solutions.

Respiration Measurement with Fish

Automated Respirometry

Automated measurements of O2 consumption rates in aquatic organisms.

Coaster CFG


A variety of accessories like connectors to different vessels is available.

Tools & Utilities