Cerium dioxide nanoparticles (CeO2NPs) with a high value of ζ‐potential (≥30 mV) have been synthesized in reverse microemulsions and they are able to form the high‐stable aqueous suspension without any additional stabilizers. It has been shown that the interaction of such CeO2 NPs with transport proteins, such as BSA, affects their molecular conformation and biochemical activity. The observed changes in the UV‐absorbance spectrum and intrinsic fluorescence quenching of BSA molecule are indicative of the occurrence of structural changes caused by binding with the surface of CeO2NPs. Low affinity between BSA and CeO2 NPs has been confirmed by differential scanning calorimetry (DSC). Moreover, CeO2NPs can act as regenerative free‐radical scavengers, and their antioxidant activity depends on the concentration. The positive charge of CeO2NPs can be attributed to their low toxicity toward human malignant lymphocytes MT‐4 and breast cancer cells MCF‐7 however, the morphofunctional features of MCF‐7 cells interacting with CeO2NPs are indicative of the decrease in oncogenicity.

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The article is devoted to the theoretical aspects of the development of the effective method for the removal of protein-bound uremic toxins. It is shown that the methods of flow and differential scanning microcalorimetry are sufficient enough for the evaluation of the degree of ligand loading of human serum albumin with protein-bound uremic toxins. The molecules of albumin isolated from blood plasma of the patients being kept on chronic dialysis are demonstrating significant alterations of conformation and complex-forming properties, the correction of which by conventional methods of extracorporeal detoxification (exhaustive dialysis, treatment on synthetic SCN carbons) are practically ineffective. Deliganding of uremic albumin may be successfully performed on conventional carbon haemosorbents upon preliminary separation of blood plasma and its dilution with acetate buffer 1:1 at pH = 5.08. Treatment of the whole blood of patients onto new mass-fractal deliganding carbon, i.e., hemosorbents of HSGD trademark. These HSGD haemosorbents quite effectively could be used for restoration of main parameters of uremic HAS molecules conformation and ligand-binding activity simultaneously with hemodialysis upon the protection by locally performed citrate anticoagulation as an easier and cheaper method for the removal of protein-bound uremic toxins.

The liver failure means inability to perform its normal synthetic, biotransformation and excretory functions. The disturbance of metabolic processes leads to the development of "metabolic endogenous intoxication" resulting in oxidative stress. Oxidative stress initiates the processes of oxidation of amino acid residues of blood plasma proteins causing the changes in their structure and functions. The effect of administration of highly activated porous carbonic enterosorbents on oxidative stress manifestations and molecular conformation of serum albumin in blood of experimental animals with acute liver failure induced by carbon tetrachloride (CCl 4) needs to be investigated. Two forms of activated carbonic enterosorbents such as AC1 (primary beads with the range of diameters of 125-250 μm) and AC2 (secondary granules prepared from micronized AC1 having the mean particle size of~1 μm) derived from phenol-formaldehyde resin were used in rat model with CCl 4 intoxication. The total level of reactive oxygen species (ROS) in blood plasma, the activity of catalase (CAT) in blood hemolysates; the content of reduced glutathione (GSH) in liver homogenates, and the level of oxidative modification of proteins (OMP) such as aldehyde-dinitrophenylhydrazone (A-DNPH) and ketone-dinitrophenylhydrazone (K-DNPH) derivatives in blood plasma and liver homogenates were determined. In addition, the level of pro/antioxidant ratio in blood hemolysates and the content of lipid peroxidation product-malondialdehyde (MDA), in blood plasma and liver were determined. Melting thermograms of blood plasma proteins (BPP) and molecular conformation changes of serum albumin were analyzed by biophysical methods (differential scanning microcalorimetry and spectrofluorimetry). The extent of CCl 4-induced oxidative damage in blood and liver of experimental animals was shown to be less expressed for AC1 in comparison with AC2 enterosorbent. However, AC2 used in the form of secondary granules positively influenced some biophysical properties of albumin molecule (temperature of melting, shape of melting endotherm and intrinsic fluorescence) after rats exposure to CCl 4. In general, administration of both AC1 and AC2 led to the reduction of oxidative stress manifestations and partial restoration of native molecular conformation of serum albumin. These observations are promising in terms of achieving recovery of detoxification potential of organism after severe liver injury.