Colloidal Hydration Layer of Heme-Imidazole SDS micelle as Efficient Nanozyme

The thermodynamic parameters that control the non-covalent bond formation in proteins and othermacromolecules can be directly studied by differential scanning calorimetry (DSC). The most factors thatare responsible for the protein or colloid stability are hydrogen bonds to the solvent and intramolecularinteractions. Ionic strength is an important factor in hydration layer structure, which is driving force forcolloidal hydrophobic inside. Here, heme (12 μM) + imidazole (3 mM) + SDS micelle (40 mM)peroxidase-like nanozyme has shown a sharp thermal profile, observed at 66.1 ° C inside phosphatebuffer 0.2 mM. However, higher PBS concentrations (5 mM, 20 mM, 30 mM) do not show any DSCthermal profile. It seems that the observed DSC profile is related to the formation of a unique, single anddiscrete structure of peroxidase-like biocatalyst in low ionic strength due to special order of hydrationlayer. It should be noted that this nanozyme (PBS 0.2 mM) has the highest catalytic activity (28.7% ofnative horseradish peroxidase) among the other PBS concentrations. This report discusses about Role ofthe hydration force in the stability of colloids at lower ionic strengths and manifests the enzymatic activitybased on micelle colloidal solution in aqueous system.

کلیدواژه ها:

Heme-imidazole ، SDS micelle ، Nanozyme ، DSC ، hydration layer