Enhanced FTIR benchtop imaging of single biological cells

Caryn Hughes, Alex Henderson, Mustafa Kansiz, Konrad Dorling, Melody Jimenez-Hernandez, Michael D Brown, Noel William Clarke and Peter Gardner

Analyst 140 (2015) 2080-2085

Abstract

A new optical system has recently been developed that enables infrared images to be obtained with a pixel resolution of 1 micron on a bench-top instrument using a thermal source. We present here imaging data from two contrasting cellular systems that represent different challenges. Renal carcinoma cells cytospun onto CaF₂ have a largely rounded morphology and thus suffer from strong resonant Mie scattering. Skin fibroblast cells, cultured onto CaF₂ on the other hand are very spread out so scatter less strongly but are so thin they deliver extremely weak signals. Using suitable pre-processing methods, including PCA noise reduction and RMieS correction, we demonstrate that useful high resolution images can be obtained from either sample.