Interaction between immunoglobulin G and peroxidase-like iron oxide nanoparticles: Physicochemical and structural features of the protein

Peroxidase-Like Activity of Magnetic Nanoparticles in the Presence of Blood Proteins

The generation of hydroxyl radicals from hydrogen peroxide in aqueous solutions containing magnetic nanoparticles (MNPs), hemoglobin (Hb), immunoglobulin G (IgG), and human serum albumin (HSA) was determined. The dependence of the rate of formation of the oxidized product of o-phenylenediamine (o-PDA) on the concentration of MNPs in solution, as well as on the concentration of proteins, was obtained. The peroxidase-like activity of MNPs was shown to decrease in the presence of HSA and IgG, while the addition of Hb to the reaction mixture led to its decrease and increase depending on protein concentration. The obtained effects can be used in the engineering of systems based on MNPs for theranostics (in particular, for suppression of tumor growth) and in predicting the ability of particles to catalyze the generation of reactive oxygen species (ROS) in vivo.

A Review of the Use of Metallic Nanoparticles as a Novel Approach for Overcoming the Stability Challenges of Blood Products: A Narrative Review from 2011-2021

PURPOSE

To obtain safe and qualified blood products (e.g., platelets, plasma, and red blood cells), various limitations such as limited shelf life (especially for platelets) and stability must be addressed. In this review study, the most commonly used metal nanomaterials (e.g., gold, silver, iron, and magnetic) reported in the literature from 2011 to 2021 were discussed owing to their unique properties, which provide exciting approaches to overcome these limitations and improve the stability, safety, and quality of blood products. Novelty: This study reviews for the first time the results of studies (from 2011 to 2021) that consider the effects of various metallic nanoparticles on the different blood products.

RESULTS

The results of this review study showed that some metallic nanoparticles are effective in improving the stability of plasma proteins. For this purpose, modified Fe₃O₄ magnetic nanoparticles and citrate-AuNPs protect albumin products against stressful situations. Also, SiO₂ microspheres and silicacoated magnetite nanoparticles are highly capable of improving IgG stability. ZnO nanoparticles also reduced thrombin production, and protein-coated GMNP nanoparticles prevented unwanted leakage of factor VIII through blood vessels. Furthermore, the stability and longevity of erythrocytes can be improved by AuNP nanoparticles and Zr-based organic nanoparticles. In addition, platelet storage time can be improved using PEGylated Au and functionalized iron oxide nanoparticles.

SUGGESTION

According to the results of this study, it is suggested that further research should be conducted on metal nanoparticles as the most promising candidates to prepare metal nanoparticles with improved properties to increase the stability of various blood products.

Albumin-Functionalized Iron Oxide Nanoparticles for Theranostics: Engineering and Long-Term In Situ Imaging

Magnetic nanosystems (MNSs) consisting of magnetic iron oxide nanoparticles (IONPs) coated by human serum albumin (HSA), commonly used as a component of hybrid nanosystems for theranostics, were engineered and characterized. The HSA coating was obtained by means of adsorption and free radical modification of the protein molecules on the surface of IONPs exhibiting peroxidase-like activity. The generation of hydroxyl radicals in the reaction of IONPs with hydrogen peroxide was proven by the spin trap technique. The methods of dynamic light scattering (DLS) and electron magnetic resonance (EMR) were applied to confirm the stability of the coatings formed on the surface of the IONPs. The synthesized MNSs (d ~35 nm by DLS) were intraarterially administered in tumors implanted to rats in the dose range from 20 to 60 μg per animal and studied in vivo as a contrasting agent for computed tomography. The long-term (within 14 days of the experiment) presence of the MNSs in the tumor vascular bed was detected without immediate or delayed adverse reactions and significant systemic toxic effects during the observation period. The peroxidase-like activity of MNSs was proven by the colorimetric test with o-phenylenediamine (OPD) as a substrate. The potential of the synthesized MNSs to be used for theranostics, particularly, in oncology, was discussed.

The influence of pH and ionic strength on the interactions between human serum albumin and magnetic iron oxide nanoparticles

Human serum albumin (HSA) is a very well-characterized protein, which has already been used for many biocompatible coatings. We hypothesized binding between HSA and magnetic iron oxide nanoparticles (MNPs) as well as HSA coating stability to be pH- and ionic strength-dependent. The impact of phosphate buffer on protein coating was studied at varying pH (6.0, 6.6, and 7.5) and ionic strengths (0.15 and 0.30 M NaCl) using different physicochemical methods. In addition, the stability of HSA coatings on MNPs was studied by means of UV/visible spectrophotometry, dynamic light scattering, and electron magnetic resonance. We used differential scanning calorimetry (DSC) to determine the differences in the change of enthalpies and denaturation temperatures of HSA in various buffer conditions and on the surface of the particles. The binding thermodynamics of HSA and MNPs were determined by isothermal titration calorimetry (ITC), and it was also dependent on pH and ionic strength. The stability of adsorbed layer on MNPs decreases with increasing pH [from weakly acidic (pH 6.0-6.6) to slightly alkaline (pH 7.5)], as well as with an increase of ionic strength. This study develops stable HSA coating on MNPs which might be applied to a wide range of biomedical applications.

Nonspecific interaction between plasminogen and modified magnetic iron oxide nanoparticles

The magnetic particles modified with silicon dioxide (SiO₂) and amino groups (-NH₂), as well as the magnetic particles modified with human serum albumin (HSA) were synthesized using the approaches we developed before and characterized by physico-chemical methods in this study. Plasminogen was chosen as a model protein since plasminogen plays a major role in the fibrinolytic system and plasminogen level correlates with different pathologies and conditions. For the first time it has been carried out qualitative and quantitative assessment of plasminogen nonspecific binding (noncovalent adsorption) by the particles in buffer and plasma solutions. The fibrinolytic activity of plasminogen on the surface of the particles has been measured by the aid of commercially available kits and appeared to be 28-30% of its initial value. Plasminogen desorption from the surface of particles was studied in phosphate buffer with NaCl and ε-aminocaproic acid. Despite nonspecific plasminogen binding is an undesirable process, the data obtained is valuable for further modification of particles for high-specific proteins extraction from biological fluids or transport of plasminogen by the particles. The perspectives of particles modified with SiO₂ and -NH₂, and particles modified with HSA for isolation of protein analytes and their quantitative assessment thereafter have been discussed.