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Trace Oxygen Measurements with High Spatial Resolution
Needle-Type Oxygen Microsensor NTH-PSt8
The end of a glass fiber is coated with oxygen-sensitive material with a measurement range of 0 – 10 % oxygen. This tip (230 µm) is protected inside a stainless steel needle and can be extended for measurements. As long as the sensor tip is retracted and protected by the needle the microsensor can be pierced through septum rubber or any other harsh material. With its small tip size and fast response time (t90 < 3 s) this sensor is ideally suited for trace oxygen measurements in research and packaging applications.
- High spatial resolution
- High temporal resolution (t90 < 3 sec.)
- No consumption of oxygen
- Signal independent of flow velocity
- Measures liquids as well as in gas phase
Applications
Tissue Engineering
Oxygen microsensors measure the oxygen content in various volume compartments of the tissue engineering constructs. To do so, hair-thin sensors are inserted into the constructs and the oxygen content is measured online. In this way, the oxygen partial pressure is measured with a high local resolution and correlated with the constructs tissue quality (composition of the extracellular matrix).
Packaging & Quality Control
Oxygen inside packaging can lead to oxidative deterioration of certain products. Therefore, determination of the oxygen content within packages or pharmaceutical vials is of essential importance to ensure both the filling quality and the long-term storage stability. With our micro-invasive needle-type oxygen microsensors we offer a simple tool to determine residual oxygen both in the headspace and in liquids. The septum of the vial or package is pierced with the needle and the sensor is extended for measurement. As the measurement is made inside the package no error-prone and time consuming sampling is necessary. These oxygen microsensors are ideal tools for quality control in the food & beverage, packaging, and pharmaceutical industries.
Technical
| Specifications* | Gaseous & Dissolved O2 | Dissolved O2 |
|---|---|---|
| *data for microsensors TF = flat-broken sensor tip with 230 μm diameter **after two-point calibration as described in the manual | ||
| Measurement range | 0 – 10 % O2 0 – 100 hPa | 0 – 4.5 mg/L 0 – 140 µmol/L |
| Limit of detection | 0.007 % oxygen | 3 ppb |
| Resolution | ± 0.002 % O2 at 0.008 % O2 | ± 0.7 ppb at 3 ppb |
| Accuracy at + 20 °C** | ± 3 ppb or ± 3 % rel. | |
| Measurement temperature range | from 0 to + 50 °C | |
| Response time (t90) | < 3 sec. (gas) | < 10 sec. (liquid) |
| Properties | ||
| Compatibility | Aqueous solutions, ethanol, methanol | |
| No cross-sensitivity | pH 1 – 14 | |
| Cross-sensitivity | Organic solvents, such as acetone, toluene, chloroform or methylene chloride | |
| Sterilization procedure | Ethylene oxide (EtO) | |
| Cleaning procedure | 3 % H2O2 | |
| Calibration | Two-point calibration with oxygen-free environment (nitrogen, sodium sulfite) and a second calibration value optimally between 2 % and 4 % oxygen | |
| Storage stability | 60 months provided the sensor material is stored in the dark at room temperature | |
Related products
Resources
FAQs
Can I measure inside a tissue with fiber optic microsensors?
How can I prevent oxygen or pH microsensors from breaking when measuring profiles across tissue?
How do I import data into excel from a text file containing measurement data?
How do I measure the oxygen content in small headspace packages with a needle-type oxygen microsensor?
How do I use the oxygen microsensor for measurement in ice?
How does an oxygen sensor work?
How does salinity affect the oxygen measurement?
How does temperature affect the oxygen measurement?
How often will I have to exchange the microsensor?
I can see that about 1 mm of the tapered sensor tip of an oxygen microsensor is coated with material. Is all of this coating sensitive to oxygen and where exactly do I measure?
Is there a recoating service for the needle-type microsensors?
The needle tip of the microsensor is vibrating or not moving smoothly when I try to insert it in the sample with the Manual Micromanipulator. What can I do?
The Stern-Volmer-equation
What is the correct way for handling an oxygen or pH microsensor?
What is the difference between tapered and flat-broken microsensor tips?
What is the time of delivery?
Which substances can interfere with the optical O2, pH and CO2 measurements?
Manuals
Brochures
Software
PreSens Oxygen Calculator version 3.1.1 - Windows 7/8/10