Airyscan superresolution microscopy: A high-throughput alternative to electron microscopy for the visualization and analysis of fossil pollen

Abstract

Airyscan confocal superresolution microscopy is a new optical technique that can detect morphological features smaller than the diffraction limit of light. It captures both the external and internal ornamentation of modern and fossil pollen. Airyscan combines the ease of use of optical microscopy methods, such as confocal and brightfield microscopy (BM), with the high-resolution imaging of electron microscopy (EM). Modern and fossil pollen grains were imaged using Airyscan, BM, and EM to assess the viability of Airyscan as an alternative for EM. Our results demonstrate that: (1) Airyscan can capture diagnostic features of extant and fossil pollen similar to EM; (2) one-to-one comparisons of Airyscan images with other optical methods are possible (e.g., BM and conventional confocal); (3) Airyscan captures three-dimensional data, allowing reconstruction of pollen grains in different views; and (4) the time and effort required for Airyscan imaging is significantly less than that for EM. This paper demonstrates that Airyscan superresolution microscopy is a high-throughput alternative for morphological analyses of pollen specimens.