Investigation of porous silica nanostructures in diatoms isolated from Kurichi and Sulur lakes of Coimbatore, India using field emission scanning electron microscopy

•Nanoporous structures of pennate diatoms in Coimbatore lakes, India studied.•Variation in diatom nanostructure compared to reported literatures.•Changes linked to pollution of water bodies and warrants detailed study.

Diatoms are unicellular algae that possess cell wall made of silica. These diatoms play a pivotal role in synthesis of variety of silica nanostructures and have adorning morphology in nature. In the present study, we have used field emission scanning electron microscopy (FE-SEM) to investigate their morphological features like pore size, shape, and porous pattern in various diatoms isolated from Kurichi and Sulur fresh water lakes, Coimbatore, Tamil Nadu, India. Diatoms were identified as Nitzschia sp., Cyclotella meneghiniana, Coscinodiscus sp. and Cyclotella atomus based on their morphological features. The arrangement of porous nanostructures in these diatoms have been characterized. The change in the nanostructures present in the diatoms have been correlated to the contamination of water bodies.