Fast and non-contact chemical analysis - UVF

Optical analysis using fluorescence in the ultraviolet part of the spectrum (UVF) is a well-known method that is particularly suitable for the detection of biological substances. Trace amounts of oil is one common substance where UVF is used.

Ultraviolet fluorescence analysis

The UVF technology is relatively simple in theory: a sample is illuminated with UV radiation. The sample is first absorbing the light (excited) and then emitting light (emission via fluorescence). The fluorescence is detected and analysed. 

The fluorescence is shifted towards longer wavelengths than the incident light, which makes it easier to separate scattered light from the light source from the fluorescence being measured.

Sensors based on UVF have been developed since the 1970s and there are commercial instruments on the market. The technology is characterized by a high sensitivity, but a complication is that common biological substances such as bacteria and algae have fluorescence spectra that can overlap with spectra of the substance that you want to detect. UVF instrumentations therefore need to either have narrow specifications on the type of water or other media in which they operate effectively, or allow multispectral detection, ie emission detection and / or excitation takes place at a number of different adjustable wavelengths.

In its most general form (a so-called fluorometer), a UVF instrument becomes expensive and less suitable as an autonomous sensor in the field. This means that a product for a specific application area can often not be used for another.

Tailor-made systems for analysis directly in processes

RISE develops tailor-made systems based on multispectral UVF for analysis for field use, e.g. to detect oil in water. The development takes place together with the metal research institute Swerim.

UVF can provide a relatively high sensitivity (e.g. micrograms of oil per liter of raw water) and can also be used for distinction between different substances, if accurately  calibrated. In many cases, several spectrum are needed to ensure a reliable result. The technology is also very interesting for 'early warning systems' and to indicate is a process or sample volume needs further investigation and / or immediate action.

RISE' systems are built to contribute to the digitalisation of the processes involved. We strive for non-contact measurements that are:

• continuous,
• connected to the system, and
• used inline in the production flow.

The generic UVF technology at RISE is adapted to the customers' area of ​​application and packaged in robust prototypes that can be evaluated in the field for further product development.

RISE system for UVF

The basic components included in the RISE UVF system are shown in the picture: excitation takes place with a replaceable UV-LED and detection of the emission is done via a monochromator. The analysis system can be set to filter any wavelength in the ultraviolet and visible part of the spectrum.

Where do you need to measure?

Contact us to discuss more about what UVF can do for your particular application!