Studies on Lotus and Rice Leaf Surfaces by Using RIMAPS Technique

FAVRET E.; ANDRADA N.

MICROSCOPY & MICROANALYSIS

CAMBRIDGE UNIV PRESS

Año: 2009 vol. 15 p. 496 - 497

1431-9276

This research work describes the micropatterning of lotus (Nelumbo nucifera) and rice (Oryza sativa) leaf surfaces by analyzing their RIMAPS spectra. These surfaces are superhydrophobic, which means that their static contact angles are greater than 150º and their sliding angles (SA) are less than 10º. The surface of the lotus leaf is uniformly textured with 10 microns size protrusions. The arrangement of these protrusions seems to be random and the sliding angle (3º) is the same in any direction. In the case of the rice leaf, epidermal cells, stomas and papillae (diameter of 4 microns) are arranged in one-dimensional order parallel to the apex direction. The SA is different if it is measured following the apex direction (SA of 4º) or following the perpendicular direction (SA of 12º). Therefore, its superhydrophobic condition is greatly influenced by the lineal arrangement of papillae. Water droplets move harder along the perpendicular direction than the parallel one. RIMAPS spectrum is a useful tool for analyzing the anisotropy of a micropattern quantitatively and finding out the minimum size of the visual field where the pattern looses its anisotropy.