Rheological Parameters Assessment in Serum, Plasma and Whole Blood of Rats after Administration of Gold Nanoparticles of Different Sizes: In vivo

Abstract

Background: The evaluation of blood rheology has been underutilised in clinical practice. We performed an array of rheological parameters measurements to quantify the responses of rat plasma, serum and whole blood to gold nanoparticles (GNPs) of different sizes. Methods: GNPs of various sizes were used in this study. Doses of 0.05 ml of the GNPs were administered to the animals via intraperitoneal injection for a period of 3 days. Blood samples with volumes of nearly 2 ml were obtained from each rat. Various rheological parameters, such as %torque, shear stress (SS), shear rate (SR), viscosity, plastic velocity, yield stress, consistency index and flow index, were measured in rat plasma, serum and whole blood. Results: The relationship between SS and SR for rat serum, plasma and whole blood showed linear behaviour with the 10, 20 and 50 nm GNPs. The viscosities of rat serum, plasma and whole blood with GNPs were decreased with increasing the SR and showed non-linear behaviour. The viscosity of blood serum and plasma was measured at a range of shear rates from 200 to 1375 s-1, while the viscosity of whole blood was measured at 75 to 600 s-1. Conclusions: The GNP size has a considerable influence on the various rheological parameters for rat blood at a fixed temperature of 37°C. The decrease in viscosity of 50 nm GNPs compared to 10 and 20 nm GNPs may be attributed to decrease in number of NPs and GNP surface area. It can be concluded that the GNPs probably cause erythrocyte deformability, and their interactions with blood proteins may cause a decrease in serum, plasma and whole blood viscosities under a given level of applied SS and SR compared to the control. This study suggests that further experimental work taking nanoparticle surface properties into consideration should be performed.