Using near-infrared spectroscopy to shine light into the causes of hay fever

Using near-infrared spectroscopy to shine light into the causes of hay fever

Ever been victimised by explosive pollen levels during the summer months?  Hay fever is not fun! Puffy, red faces, itchy eyes, and runny noses are all down to our immune system’s complicated relationship with pollen. But do you know, using near-infrared (NIR) spectroscopy, it is possible to name and shame the worst plant offenders! Interesting, isn’t it? 

Widely used in a range of industries spanning from pharmaceutical, chemical, and food, NIR can be used to rapidly and reliably identify pollen count in the air. This technology can replace traditional, optical spectroscopy methods, which are time-consuming and not as accurate.  

How does NIR spectroscopy work to achieve this?

NIR spectroscopy uses light in the near-infrared space between the visible and infrared regions. The wavelength of these spectra is between 800nm and 2500nm. To get an understanding of just how minute these wavelengths are; a human hair average about 60,000nm in diameter, while a grain of pollen is between 15,000nm and 200,000nm.  

As the sample material is subjected to a NIR pulse, it absorbs specific wavelengths depending on what chemical bonds the sample material possesses. The intensity of the absorbance can be related to the concentration within the sample. From this, we can understand the chemical makeup of a sample, or in the case of pollen, to what species it belongs.  

Who are the worst offenders that steal some of the shine out of summer?

Unsurprisingly, your garden lawn is among the biggest producers of pollen. In the UK and Ireland, 90% of hay fever sufferers are allergic to grass pollen alone. 

Interestingly, different regions have differing leading sources of pollen. NIR spectroscopy can be used to establish the composition of pollen in the air. For example, the most common pollen allergens in Scandinavia and Spain is birch and olive tree pollen, respectively.  

NIR spectroscopy beyond pollen studies

NIR spectroscopy is an extremely flexible technology that opens a world of applications in chemical analysis. Some of the use cases are;

  • Analysing constituents of liquid – from milk to paint
  • Testing the fertility in agriculture – nutrient, or moisture content of the soil, 
  • Determining the fiber content of textiles
  • Measuring the density, moisture content, and chemical composition of powders in the pharma industry 
  • Automatic detection and separation of plastics from refuse
  • Measuring the levels of pollution in rivers.  

The possibilities of NIR spectroscopy are truly boundless!