AbstractIn order to prepare nanoparticles, corn cobs were treated with sodium hydroxide in the range 0-6 mole/litre (0-24% of sodium hydroxide on oven dry basis) at 165 oC for 1.5 h at a liquor to solid ratio of 4.5:1. The sample obtained at the optimised condition (4.5 mole/litre) was washed with deionised water, disintegrated, and filtered through 80 mesh screens. Powder thus obtained was delignified by acidified sodium chlorite and dried in a vacuum oven to constant weight. Dried powder was further separated by 270 mesh screens. An average particle size approximately equal to 22 nm was observed by Transmission Electron Microscopy (TEM). Its crystallinity was determined by XRD analysis. The aggregated particle size was observed in the micron range by Scanning Electron Microscopy (SEM).