Designed for research applications within:
Biomedical Sciences
Bulk and Bioreactors
Environmental sciences

O2 microoptode

Optode sensor technology

Unisense offers optode sensor technology with full integration to our existing laboratory systems. The optical sensor technology gives you a cost-effective and robust oxygen sensor that enables a great number of applications. Read more...

Read More
Technical Data
Ordering Information & Sizes
Manuals & Videos
O2 MicroOptode

Full integration to lab systems

Simple two-point calibration and temperature compensation ensures ease-of-use, and the Unisense software suite allows you to combine the oxygen MicroOptode with our wide selection of microsensors. You can use the MicroOptodes with our 1 or 4 ch Opto UniAmp, or the Field Opto UniAmp.

The Unisense oxygen optodes are designed for research applications such as:

  • Respiration
  • Biomedicine
  • Bulk and bioreactors
  • Environmental sciences
  • Profiling
Opto-F1 w. sensor

Oxygen MicroOptode principle

The measuring principle of the oxygen optode is based on Unisense technology and delivers unparalleled performance within our core application segments . Luminescence quenching caused by collision with oxygen molecules makes it possible to determine the oxygen concentration. More oxygen molecules will result in a lower emission signal, providing a measurement of the oxygen concentration in the sample.

The optode fiber is built into a steel needle. This allows you to retract the fiber into the needle for complete protection, e.g. when piercing a rubber septum. When the needle tip reaches the measuring site, the fiber can be pushed out into the sample and measure the oxygen concentration.

Customized versions with fixed exposure for e.g. profiling application and Eddy Covariance are also available.

Combined with our Opto UniAmp, the optical sensor technology gives you following advantages:

  • Zero-noise temperature compensation
    Accurate oxygen quantification by unmatched temperature compensation
  • Ambient light filtering technology
    Improved performance under fluctuating ambient light conditions, e.g. in situ
  • Bleach protection
    Novel multi-component modulation improves lifetime with 50%
  • 50 µm tip
    Optimized design for true microprofiling
  • Fast 430 µm sensor
    For Eddy Covariance and other applications requiring <0.3s response times
  • Robust 3000µm sensor
    For bulk and long-time monitoring applications
  • E2PROM
    Plug'N'Play with unique sensor identification and calibration retrieval
Opto T-drift_700x480 EC Optode_1400x800
...see more
Cables & Connectors
Response Time
Cables & Connectors
Item Standard Options Extra price for option selection
Cable length 2.0 m Customized available Yes, depends on length
Connector ST connector with E2PROM
Attribute Standard Options Extra price for option selection
Guaranteed lifetime Opto-430 1 year or 1.5 million datapoints, whichever comes first
Guaranteed lifetime Opto-50 and Opto-430 Fast 1 year or 1.0 million datapoints, whichever comes first
Guaranteed lifetime Opto-3000 1 year or 3.0 million datapoints, whichever comes first
Expected lifetime +3 years in darkness at room temperature
Temperature range 0-50°C
Temperature coefficient Temperature compensation when using temperature sensor (ZNTC)
Range 0-100% O2 (0-45 mg/L) | Optimal 0-50% O2 (0-23 mg/L)
Detection limit 0.02% (0.01 mg/L) | 50 µm: 0.05% (0.025 mg/L)
Waterproof Yes
Pressure tolerant sensing tip Yes
Position of sensing tip MR, bare fiber, fixed exposed, retractable needle
Spatial resolution Equals tip size, special slender 50 µm version
Response Linear when calibrated
Interference Some organic solvents and chlorine.
No cross-sensitivity pH 1-14, CH4, H2, CO2, H2S, CH3SH, NH3, any ionic species
Response Time
MicroOptode Response time (90%)
Opto-50 <5 s
Opto-430 <3 s
Opto-430 Fast <0.3 s
Opto-3000 <15 s
Ordering information & Sizes
Ordering information & Sizes
Opto MicroOptode Fiber diameter and description
Opto-50 50 µm for profiling, needle type: 0.6 x 25 mm
Opto-430 430 µm, needle type: 1.1 x 25 mm
Opto-430 Fast* 430 µm Fast (see note below), needle type: 1.1 x 25 mm
Opto-MR 430 µm (for MicroRespiration)
Opto-SL-1/4 FT-cell 1/4'' Swagelok Tee
Opto-PEEK-1/8 FT-cell 1/8'' PEEK Tee
Opto-PEEK-1/16 FT-cell 1/16'' PEEK Tee
Opto-FT-GLASS-6 Glass FT-cell 6 mm outer diameter
Opto-FT-GLASS-8 Glass FT-cell 8 mm outer diameter
Opto-3000 3,000 µm fiber with steel 5 cm cap
Opto-3000-ST-1/4 1/4'' steel tube
Temp-UniAmp Temperature sensor
Opto-Field 50 µm or 430 µm for Field Opto UniAmp
Opto-Field 430 Fast 430 µm Fast for Eddy Covariance
Opto-Field 3000 3,000 µm fiber with steel 5 cm cap for Field Opto UniAmp
Opto-Temp Field Temperature sensor for Field Opto UniAmp

*Maximum sampling speed is 1 Hz on lab instruments and 10 Hz on Field Opto UniAmp. In EC-mode up to 16 Hz on Field Opto UniAmp.

Video Guides

Quick Guide MicroOptodes
Quick Guide MicroOptodes

A short presentation of how we make microoptodes, how you can use them, and a look at specifications and customizations.

Measuring Oxygen
Oxygen - optode or amperometric microsensor?

CSO Lars Hauer Larsen reviews the pros and cons of these sensor types for a given application.

Be the first to learn about new products, application notes, publications, and events

    We will use your e-mail for our newsletter. That's it.
    You can unsubscribe at any time.

    You can also find us on Twitter, LinkedIn, and YouTube.