Chemical imaging of secondary cell wall development in cotton fibers using a mid-infrared focal-plane array detector

Market demands for cotton varieties with improved fiber properties also call for the development of fast, reliable analytical methods for monitoring fiber development and measuring their properties. Currently, cotton breeders rely on instrumentation that can require significant amounts of sample, which complicates fiber development studies. Herein, we explored the use of high-resolution, Fourier-transform infrared (FT-IR) microscopy to examine cotton fiber secondary cell wall development in single fibers. Notably, there was a marked intensity increase for the C-O bending region near 1015 cm–1 and the C-H stretch at 2900 cm–1. These changes agree with those observed with macroscopic FT-IR tests. Chemical distribution maps and principal component analysis plots visually depict these spectral changes. Our results suggest the FT-IR microscopy can potentially be utilized as a tool to monitor and assess important fiber properties, such as cotton maturity, during fiber development.