Bell Shape Curves of Hemolysis Induced by Silver Nanoparticles: Review and Experimental Assay

Abstract

The hemolytic activity assay is a versatile tool for fast primary toxicity studies. This work presents a systematic study of the hemolytic properties of ArgovitTM silver nanoparticles (AgNPs) extensively studied for biomedical applications. The results revealed an unusual and unexpected bell-shaped hemolysis curve for human healthy and diabetic donor erythrocytes. With the decrease of pH from 7.4 and 6.8 to 5.6, the hemolysis profiles for AgNPs and AgNO3 changed dramatically. For AgNPs, the bell shape changed to a step shape with a subsequent sharp increase, and for AgNO3 it changed to a gradual increase. Explanations of these changes based on the aggregation of AgNPs due to the increase of proton concentration were suggested. Hemolysis of diabetic donor erythrocytes was slightly higher than that of healthy donor erythrocytes. The meta-analysis revealed that for only one AgNPs formulation (out of 48), a bell-shaped hemolysis profile was reported, but not discussed. This scarcity of data was explained by the dominant goal of studies consisting in achieving clinically significant hemolysis of 5–10%. Considering that hemolysis profiles may be bell-shaped, it is recommended to avoid extrapolations and to perform measurements in a wide concentration interval in hemolysis assays.

Erythrocyte Vulnerability to Airborne Nanopollutants

“…Erythrocyte osmotic fragility test: The methodology utilized for the present study includes an accurate control for the possible presence of blood diseases that might generate false positive or false negative results. Hemolysis caused by different types of nanoparticles (polystyrene, titania, magnetite, gold, silver, silica, zincite, and selenium) has been widely reported in the literature [ 33 , 37 , 59 , 60 , 61 ]. The osmotic fragility (OF) test is commonly used to evaluate the erythrocyte membrane and diagnose hemolytic anemia.…”

“…A fourth shortage of such tests is related to the difficulties arising from the translation of tests designed for biomedical environments into toxicological areas. Unlike nanomaterials designed for biomedical applications that have specific applications and controlled doses, our exposure to nanopollutants is chronic and cumulative, and one concern is how we can assess that effect [ 9 , 37 ]. In addition to the hemolysis test, studying the morphological changes induced by nanopollutants can provide information on potential short- and long-term effects.…”

Allolobophora caliginosa coelomic fluid and extract alleviate glucocorticoid-induced osteoporosis in mice by suppressing oxidative stress and regulating osteoblastic/osteoclastic-related markers

“…The hemolysis test was performed according to Luna et al 20 In brief, erythrocytes were separated from plasma by centrifugation of the whole blood samples at 3000 rpm and washed three times with isosaline of equal volume (0.85%, pH 7.2). Erythrocytes were resuspended in 10% v/v isosaline suspension.…”

“…Anti-inflammatory activity of AcCF and AcE using Heat-induced hemolysis protocol. The hemolysis test was performed according to Luna et al 20 In brief, erythrocytes were separated from plasma by centrifugation of the whole blood samples at 3000 rpm and washed three times with isosaline of equal volume…”

A Comparative Study of Cancer Cells Susceptibility to Silver Nanoparticles Produced by Electron Beam

“…This approach ensures the production of standardized AgNPs with high bioactivity and high stability in solution [ 22 ], which was used in biotechnology, medicine, veterinary, and agriculture [ 23 , 24 , 25 ]. At the same time, AgNPs synthesized with an electron beam and stabilized with PVP and PH showed low toxic effects towards hemolysis [ 26 ], and human lymphocytes [ 27 ]. The effect of AgNPs on tumor cells is of particular interest.…”