Pollen analysis by FTIR spectroscopy : a feasibility study for an automated method

Abstract

Pollen forecasting by optical microscopy remains is costly and time-consuming, and suffers from uncertainties connected to the visual inspection performed by the operator. An automated method for pollen analysis has been requested during the past few decades, but no attempt has proven to be sufficiently accurate and practical to implement. Simultaneously, prevalence of allergic rhinitis (hay fever) has increased noticeably the past century, reducing the quality of life for approximately 20 % of the global population. An improved method of pollen analysis therefore has the potential to better enhance the quality of life for pollen allergy sufferers.

This study examines the potential of FT-IR spectroscopy combined with multivariate analysis for a more accurate and detailed pollen count. Five different types of pollen was measured, and Principal Component Analysis (PCA) was applied on the infrared spectra, using the software The Unscrambler X, version 10.3. Instead of the commonly used KBr pellet, the pollen grains were embedded in paraffin between polyethylene foils, both for the practical implication as such foil easily can be used in pollen samplers, and to avoid scattering.

The study offers an analysis of socio-economic consequences of allergies, and identifies the market components, market interest, cost, and price for a pollen analysis service (PollenID) to be based in Ås, Norway.

Concerning the pollen analysis method, PCA plots show clear separation between pollen species, in addition to groupings among pollen of the same species. Due to the paraffin and foil embedding, scattering was almost completely avoided. The method needs further development to be fully automated, but demonstrates remarkable potential.

However, the market research indicates limited interest for pollen analysis, possibly because this service is not available today, and the target groups might not see the need for a customized pollen forecast. The estimated operation cost was estimated to 1.9 million NOK per year, and the price suggested was 200 NOK per sample, to make the analysis more available to the public.