Oxygen deficient MoO nanoparticles as peroxidase substitutes, their substrate-nanozyme interactions and real time validation in human serum sample.

Oxygen deficient molybdenum oxide nanosheet (Od-MO Nshs) was synthesised by hydrothermal method and its peroxidase-like activity was established with 3,3',5,5'-Tetramethylbenzidine-(TMB) and o-phenylenediamine dihydrochloride-(OPD) as a co-substrate in presence of Hydrogen peroxide (HO) and catalytic parameters were compared with horseradish peroxidase-(HRP) enzyme. Optimization was carried out for physical and chemical parameters. Synthesised nanoparticles-(NPs) were characterized for size, shape, composition oxidation state etc.

Evaluation of peroxidase mimicking behaviour of VO nanozymes with various morphologies and its application as glucose sensor via cascade mechanism in human serum samples.

A simple spectrophotometric method is presented for quantifying glucose and HO using p-aminophenol sulfate-(PAP) & N-(1-Naphthyl) ethylenediamine dihydrochloride-(NEDA) as novel chromogenic reagents with different morphological VO nanoparticles (NPs) as peroxidase mimicking nanozyme. For glucose, the method was linear in the range of 0.0289 and 0.

A quantitative method for the detection and validation of catalase activity at physiological concentration in human serum, plasma and erythrocytes.

A novel method has been proposed to develop a simple, rapid, sensitive and affordable chromogenic attempt for the quantification of catalase (CAT) activity in blood samples. The method is based on the oxidation of pyrocatechol (PC) to give quinone form which by oxidative coupling with aminyl radical of 4-aminoantipyrine (4-AAP) resulting from HO/CAT to produce a pink colored quinone-imine product with λ = 530 nm in a 100 mmol/L of tris buffer of pH 9.8 at room temperature (30 °C).

Quantification of creatinine in biological samples based on the pseudoenzyme activity of copper-creatinine complex.

Glomerular filtration rate (GFR), the marker of chronic kidney disease can be analyzed by the concentration of cystatin C or creatinine and its clearance in human urine and serum samples. The determination of cystatin C alone as an indicator of GFR does not provide high accuracy, and is more expensive, thus measurement of creatinine has an important role in estimating GFR. We have made an attempt to quantify creatinine based on its pseudoenzyme activity of creatinine in the presence of copper.

Determination of catalase activity using chromogenic probe involving iso-nicotinicacidhydrazide and pyrocatechol.

A biocatalatic pathway involving chromogenic probe has been proposed for the determination of catalase activity by means of iso-nicotinicacidhydrazide (INH) and pyrocatechol (PC). The assay is based on the enzymatic consumption of hydrogen peroxide using INH-PC system. The response of the catalase activity was ascertained by the rate of the reaction involving 14.

Simple and sensitive method for the quantification of total bilirubin in human serum using 3-methyl-2-benzothiazolinone hydrazone hydrochloride as a chromogenic probe.

We here describe a new spectrophotometric method for measuring total bilirubin in serum. The method is based on the cleavage of bilirubin giving formaldehyde which further reacts with diazotized 3-methyl-2-benzothiazolinone hydrazone hydrochloride giving blue colored solution with maximum absorbance at 630 nm. Sensitivity of the developed method was compared with Jendrassik-Grof assay procedure and its applicability has been tested with human serum samples.