Differential propensity of citrate- and polyethylene glycol-coated silver nanoparticles to bovine hemoglobin.

Propensity of two different silver nanoparticles (Ag-NPs) to bovine hemoglobin (BHb) was investigated by means of spectroscopic methods. We have combined spectrophotometric and calorimetric methods to show that there is no significant interaction between citrate-coated Ag-NPs and BHb at physiological pH and 20°C. However, our previous results show that polyethylene glycol-coated Ag-NPs strongly bind to Hb and effect on the secondary and tertiary structures of BHb. Thus, a suitable surface coating and modification of surface charge would increase the NPs safety and reduce adverse biological responses.