A simple uric acid assay by using 3-hydroxytyramine as a chromogenic colorimetric sensor in human serum samples: Density functional theory supported mechanistic approach Honnur Krishna, Avinash Krishnegowda, Shivakumar Anantharaman, Kumar Shrestha Ashwinee, A Edalli Vijayalakshmi Journal of the Chinese Chemical Society, 2023 A simple, fast, sensitive, convenient, and economical accurate enzymatic colorimetric sensor is developed for the quantification of the clinically important biomarker uric acid (UA) in human serum samples. The method is based on the quantification of UA using 3‐hydroxytyramine (3‐HT) as a chromogenic substrate by using peroxidase (POD) and uricase (UOx). UOx catalyzes the oxidation of UA where H2O2 is generated in‐situ to produce allantoin and CO2. The POD in oxidative coupling of peroxide in presence of 3‐HT, forms an intense orange‐colored product with λmax = 500 nm. The reaction was carried out in a citric acid‐tripotassium‐citrate buffer (12.5 mM) of pH = 6.8 at room temperature. Computational calculations were done by Gaussian‐16 employing the B3LYP functional basis set. The standard curve for UA was found to be linear between 12.3–297.3 and 3.07–396.5 μM by rate and fixed time method, respectively. The LOD and LOQ for UA were 1.5 and 2.9 μM, respectively. Within‐day and day‐to‐day precision was 1.50–3.07 and 3.10–4.16% (n = 7), respectively. The accuracy ranges for UA concentrations of 24.7, 198 and 297.3 μM were 87%–101.50%, 90%–105%, and 89%–107%, respectively. The UA recovery range by the proposed method was 98.00%–100.47% with a mean recovery of 99.5% and has A good correlation coefficient of 0.981 with the standard method.
Nanostructured ZnO&CoO Doped Transition Metal Oxide Nanoparticles as Antibacterial Agents 14th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2023, 2023
An Account of the Influence of TMDC Anodic Materials on Li/Na-ion Battery Capacity 14th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2023, 2023
Spectrophotometric Assay based on Horseradish Peroxidase- Catalysed Hydrogen Peroxide using Amino Antipyrine and Resorcinol as Chromogenic Reagents for Sensitive Detection of Peroxidase in Plant Extracts 14th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2023, 2023
Current Review of Nanozymes 14th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2023, 2023
Analytical Determination of Hemoglobin by Spectrophotometric Method 14th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2023, 2023
Creatinine conjugated copper oxide nanomaterial as peroxidase mimicking nanozyme and study of its biological activity RH Sadashivanna, H Krishna, A Shivakumar, NY Gangadhara, ... Next Materials 10, 101453 , 2026 2026
Phytochemicals in nutraceutical-development, regulation and market trends PK Kumar, R Rajam, AS Raj, K Avinash, P Karthik, R Sanjana Phytoceuticals in Food for Health and Wellness, 531-547 , 2026 2026 Citations: 3
Oxygen deficient MoO3 nanoparticles as peroxidase substitutes, their substrate-nanozyme interactions and real time validation in human serum sample NY Gangadhara, PK Kumar, A Krishnegowda, H Krishna, KSM Lohith, ... Journal of Pharmaceutical and Biomedical Analysis, 117119 , 2025 2025
Evaluation of peroxidase mimicking behaviour of V2O5 nanozymes with various morphologies and its application as glucose sensor via cascade mechanism in human serum samples NY Gangadhara, B Manju, PK Kumar, H Krishna, A Shivakumar, ... Biochemical and Biophysical Research Communications 762, 151758 , 2025 2025 Citations: 2
Oxalic acid capped tungsten oxide nanozyme mimicking peroxidase activity, its synthesis characterization, and kinetic data validation via spectrophotometric studies RH Sadashivanna, H Krishna, A Shivakumar, NY Gangadhara, ... Nano-Structures & Nano-Objects 40, 101340 , 2024 2024 Citations: 1
Peroxidase Mimicking V2O5 Nanozymes as the Spectrophotometric Sensor for the Determination of Glucose in Human Serum Sample Employing New Chromogenic Co-Substrates NY Gangadhara, PK Kumar, H Krishna, A Shivakumar, RH Sadashivanna, ... 2024 Citations: 1
Experimental Study on Strength and Durability Characteristics of Mortars with TiO 2 Nanoparticles HU Srivathsa, TM Prakash, K Puneeth, K Avinash International Conference on Interdisciplinary Approaches in Civil … , 2023 2023 Citations: 2
Evaluation of Strong Microwave Absorption Property of PVB-PEDOT:PSS-Ti 3 C 2 T x MXene Nanocomposite With Materials Data-Driven Discovery M Praveen Kumar, S Raga, S Chetana, K Avinash, A Dey, D Rangappa Transactions on Electrical and Electronic Materials 24 (3), 235-241 , 2023 2023 Citations: 5
A simple uric acid assay by using 3‐hydroxytyramine as a chromogenic colorimetric sensor in human serum samples: Density functional theory supported mechanistic approach H Krishna, A Krishnegowda, S Anantharaman, KS Ashwinee, ... Journal of the Chinese Chemical Society 70 (4), 894-908 , 2023 2023 Citations: 1
An Account of the Influence of TMDC Anodic Materials on Li/Na-ion Battery Capacity. R Ravikumar, ML KS, A Krishnegowda Grenze International Journal of Engineering & Technology (GIJET) 9 (1) , 2023 2023
Nanostructured ZnO&CoO Doped Transition Metal Oxide Nanoparticles as Antibacterial Agents. KKP Kumar, A Krishnegowda Grenze International Journal of Engineering & Technology (GIJET) 9 (1) , 2023 2023
Spectrophotometric determination of glucose in human serum samples using para‐phenylenediamine and alpha‐naphthol as a chromogenic reagent S Besagarhally Shivappa, A Krishnegowda International Journal of Chemical Kinetics 54 (12), 681-691 , 2022 2022 Citations: 5
EVALUATION OF THE ANTI-FUNGAL EFFICACY OF SILVER-DOPED NANOPARTICLES WITH METAL OXIDE NANOPARTICLES P Malathi, K Avinash Ann. For. Res 65 (1), 5263-5271 , 2022 2022
A quantitative method for the detection and validation of catalase activity at physiological concentration in human serum, plasma and erythrocytes H Krishna, K Avinash, A Shivakumar, NGS Al-Tayar, AK Shrestha Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 251, 119358 , 2021 2021 Citations: 27
Recent trends in green synthesis of ZnO nanomaterials using plant extracts M Pujar, KKP Kumar, A Krishnegowda, RH Sadashivanna Int Res J Eng Technol 8 (05), 147-156 , 2021 2021 Citations: 8
Synthesis, characterization and photoluminescence studies of samarium doped zinc sulfide nanophosphors K Ashwini, C Pandurangappa, K Avinash, S Srinivasan, E Stefanakos Journal of Luminescence 221, 117097 , 2020 2020 Citations: 30
Design Of MEMS Sensor For The Detection Of Diabetes S Shameem, DV Krishna, KS Kumar, K Avinash 2018 3rd International Conference on Inventive Computation Technologies … , 2018 2018 Citations: 1
Spectrophotometric assay of creatinine in human serum sample A Krishnegowda, N Padmarajaiah, S Anantharaman, K Honnur Arabian Journal of Chemistry 10, S2018-S2024 , 2017 2017 Citations: 69
Morphological change based Optical studies of Zinc sulphide Nanophosphor K Ashwini, C Pandurangappa, K Avinash Materials Today: Proceedings 4 (11), 12157-12167 , 2017 2017 Citations: 2
Hydroxylation of 4‐Amino‐5‐hydroxynaphthalene‐2, 7‐disulfonic Acid Monosodium Salt Catalysed by Horseradish Peroxidase and Hydrogen Peroxide: Computation of Kinetic Parameters … H Krishna, P Nagaraja, A Shivakumar, K Avinash, V Lingaiah Journal of the Chinese Chemical Society 60 (4), 452-459 , 2013 2013 Citations: 3
MOST CITED SCHOLAR PUBLICATIONS
Spectrophotometric assay of creatinine in human serum sample A Krishnegowda, N Padmarajaiah, S Anantharaman, K Honnur Arabian Journal of Chemistry 10, S2018-S2024 , 2017 2017 Citations: 69
A simple and sensitive spectrophotometric method for the determination of trace amounts of nitrite in environmental and biological samples using 4-amino-5-hydroxynaphthalene-2 … P Nagaraja, NGS Al-Tayar, A Shivakumar, AK Shrestha, AK Gowda Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 75 (5 … , 2010 2010 Citations: 57
Spectrophotometric method for the determination of chromium (VI) in water samples P Nagaraj, N Aradhana, A Shivakumar, AK Shrestha, A k Gowda Environmental monitoring and assessment 157 (1), 575-582 , 2009 2009 Citations: 44
Use of N, N-diethyl-p-phenylenediamine sulphate for the spectrophotometric determination of some phenolic and amine drugs P Nagaraja, AK Shrestha, A Shivakumar, AK Gowda Acta Pharmaceutica 60 (2), 217-227 , 2010 2010 Citations: 32
Synthesis, characterization and photoluminescence studies of samarium doped zinc sulfide nanophosphors K Ashwini, C Pandurangappa, K Avinash, S Srinivasan, E Stefanakos Journal of Luminescence 221, 117097 , 2020 2020 Citations: 30
A quantitative method for the detection and validation of catalase activity at physiological concentration in human serum, plasma and erythrocytes H Krishna, K Avinash, A Shivakumar, NGS Al-Tayar, AK Shrestha Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 251, 119358 , 2021 2021 Citations: 27
Determination of catalase activity using chromogenic probe involving iso-nicotinicacidhydrazide and pyrocatechol A Shivakumar, P Nagaraja, NA Chamaraja, H Krishna, K Avinash Journal of biotechnology 155 (4), 406-411 , 2011 2011 Citations: 22
Quantification of creatinine in biological samples based on the pseudoenzyme activity of copper–creatinine complex P Nagaraja, K Avinash, A Shivakumar, H Krishna Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 92, 318-324 , 2012 2012 Citations: 19
Spectrophotometric determination of chloroquine, pyrimethamine and trimethoprim by ion pair extraction in pharmaceutical formulation and urine P Nagaraja, AK Shrestha, A Shivakumar, AK Gowda Journal of Food and Drug Analysis 18 (4), 7 , 2010 2010 Citations: 19
Spectrophotometric determination of catecholamine using vanadium and eriochrome cyanine r P Nagaraja, AK Shrestha, A Shivakumar, NGS Al-Tayar, AK Gowda Química Nova 34, 373-376 , 2011 2011 Citations: 12
Spectrophotometric determination of the trace amount of thallium in water and urine samples by novel oxidative coupling reaction P Nagaraja, NGS Al-Tayar, A Shivakumar, AK Shresta, AK Gowda Journal of Chemistry 6 (4), 1153-1163 , 2009 2009 Citations: 12
Recent trends in green synthesis of ZnO nanomaterials using plant extracts M Pujar, KKP Kumar, A Krishnegowda, RH Sadashivanna Int Res J Eng Technol 8 (05), 147-156 , 2021 2021 Citations: 8
Simple and sensitive method for the quantification of total bilirubin in human serum using 3-methyl-2-benzothiazolinone hydrazone hydrochloride as a chromogenic probe P Nagaraja, K Avinash, A Shivakumar, R Dinesh, AK Shrestha Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 77 (4 … , 2010 2010 Citations: 8
Quantification of antioxidants in medicinal plants and foodstuffs using Ce (IV) with indigo carmine as chromogenic probe P Nagaraja, A Suma, N Aradhana, A Shivakumar, K Avinash, H Krishna Food Analytical Methods 5 (4), 909-919 , 2012 2012 Citations: 7
Rapid and sensitive spectrophotometric method for the determination of the trace amount of thallium (III) in water and urine samples by new oxidative coupling reaction P Nagaraja, NGS Al-Tayar, A Shivakumar, AK Shresta, AK Gowda Journal of the Mexican Chemical Society 53 (4), 201-208 , 2009 2009 Citations: 7
Evaluation of Strong Microwave Absorption Property of PVB-PEDOT:PSS-Ti 3 C 2 T x MXene Nanocomposite With Materials Data-Driven Discovery M Praveen Kumar, S Raga, S Chetana, K Avinash, A Dey, D Rangappa Transactions on Electrical and Electronic Materials 24 (3), 235-241 , 2023 2023 Citations: 5
Spectrophotometric determination of glucose in human serum samples using para‐phenylenediamine and alpha‐naphthol as a chromogenic reagent S Besagarhally Shivappa, A Krishnegowda International Journal of Chemical Kinetics 54 (12), 681-691 , 2022 2022 Citations: 5
Kinetic Study of Peroxidase‐Catalyzed Coupling of Benzene‐1,4‐diamine and N ‐(2‐Aminoethyl)naphthalen‐1‐amine: Development of Micromolar Hydrogen … A Shivakumar, P Nagaraja, N Aradhana, AK Gowda Helvetica Chimica Acta 93 (6), 1227-1237 , 2010 2010 Citations: 4
Phytochemicals in nutraceutical-development, regulation and market trends PK Kumar, R Rajam, AS Raj, K Avinash, P Karthik, R Sanjana Phytoceuticals in Food for Health and Wellness, 531-547 , 2026 2026 Citations: 3
Hydroxylation of 4‐Amino‐5‐hydroxynaphthalene‐2, 7‐disulfonic Acid Monosodium Salt Catalysed by Horseradish Peroxidase and Hydrogen Peroxide: Computation of Kinetic Parameters … H Krishna, P Nagaraja, A Shivakumar, K Avinash, V Lingaiah Journal of the Chinese Chemical Society 60 (4), 452-459 , 2013 2013 Citations: 3
