Characterization of dragonfly wing membranes using FTIR imaging and IR dichroism imaging

Abstract

We characterized dragonfly wings from three species, Sympetrum frequens, Orthetrum albistylum speciosum, and Sympetrum infuscatum, collected in Chitose City using Fourier transform infrared (FTIR) imaging and infrared (IR) dichroism imaging. In the FTIR images, the distribution of amide I and II bands derived from the chitin was observed across the entire vein domain; however, strong absorption for the amide bands was observed in the thicker vein domain membrane: approximately 23% of the total vein domain membrane in the wing. IR dichroism images indicated that the chitin in the thinner vein domain membrane was oriented along the primary vein.