“…[11] The pH range of maximum catalytic activity of peroxidase lies between 5 and 6 [12], whereas HRP activity retained between pH 5 and 10. [13][14][15] Among substrates, there are: aromatic amines [4], phenolic compounds [16], and some other substances [17], including immobilization of HRP in various polymer matrixes for determination of bioactive compounds [8] like hydrogen peroxide and organic peroxides [18], catecholamines and their metabolites [10], phenothiazines [19], protein biomarkers (such as Human IgG (HIgG)) [20] and biocomposites based on PDMS-SiO2NPs with co-localization/co-immobilization of enzyme (HRP or laccase) and substrate (3ethylbenzothiazoline-6-sulfonic acid (ABTS) or 3,3',5,5'teramethylbencidine (TMB)) to create a complete sensor platform or individual sensor elements. [21][22][23] HRP is widely used in laboratory work as an enzyme that catalyzes peroxidation processes, but at the same time it is an equally important analyte in medicine, chemical and pharmacological research, as well as in the biotechnological industry.…”