Model 1700

HbNPs were characterized by recording their TEM images, UV and visible spectra and FTIR spectra. The size and shape of HbNPs were measured by a high-resolution transmission electron microscope, Zeiss EM 912, at an accelerating voltage of 120 kV. TEM samples of the HbNPs were prepared by placing the product solution on to the carbon-coated copper grids, allowing the solvent to evaporate in air. UV absorbance of HbNPs dispersed in 0.1 M sodium PB (pH:7.0) was recorded in the range from 200 to 600 nm at an interval of 50 nm, using UV spectrophotometer (make: Shimadzu, Japan, model 1700). FTIR spectra of the HbNPs were measured by FTIR spectrometer (Thermo Scientific, U.S.A.) using the standard KBr method over a range of 500–4000 cm⁻¹.

The method was performed on a double-beam ultraviolet-visible (UV-VIS) spectrophotometer (Shimadzu model 1700 (Shimadzu, Kyoto, Japan)) having two matched quartz cells with a 1-cm light path.