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horseradish-peroxidase
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Removal of phenols from wastewater with encapsulated horseradish peroxidase in calcium alginate
, Article Engineering Letters ; Volume 17, Issue 4 , 2009 ; 1816093X (ISSN) ; Nejati, S ; Vossoughi, M ; Sharif University of Technology
2009
Abstract
Horseradish peroxidase was encapsulated in calcium alginate for the purpose of phenol removal. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Investigation into time course of phenol removal for both encapsulated and free enzyme showed that encapsulated enzyme had nearly similar efficiency in comparison with the same concentration of free enzyme; however the capsules were reusable up to four cycles without any changes in their retention activity
Removal of phenols with encapsulated horseradish peroxidase in calcium alginate
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 28, Issue 2 , 2009 , Pages 43-49 ; 10219986 (ISSN) ; Nejati, S ; Sharif University of Technology
2009
Abstract
Horseradish peroxidase was encapsulated in calcium alginate for the purpose of phenol removal. Considering enzyme encapsulation efficiency, retention activity and enzyme leakage of the capsules, the best gelation condition was found to be 1 % w/v of sodium alginate solution and 5.5 % w/v of calcium chloride hexahydrate. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Besides, for each phenol concentration there would be an enzyme concentration which going further than this value has no significant effect on phenol removal. Investigation into time course of phenol removal for both encapsulated and free enzyme showed that...
Horseradish peroxidase immobilization on amine functionalized carbon nanotubes: direct electrochemistry and bioelectrocatalysis
, Article Progress in Reaction Kinetics and Mechanism ; Volume 37, Number 2 , 2012 , pp. 161-172 ; Ghourchian, H. (Hedayatollah) ; Gholami, M. R. (Mohammad Reza) ; Rafieepour, H. A. (Hossain Ali) ; Sharif University of Technology
Abstract
Horseradish peroxidase (HRP) was successfully immobilized on amine functionalized TiO2-coated multiwalled carbon nanotubes (NH2 – TiO2 – CNTs) by a convenient and efficient method. Electrochemical impedance spectroscopy, cyclic voltammetry and amperometry were applied to characterize the HRP/NH2 – TiO2 – CNT nano-composite. These techniques showed that the NH2 – TiO2 – CNTs greatly enhance the electron transfer between HRP and the modified electrode. Owing to the redox reaction of the electroactive centre of HRP, the HRP = NH2 – TiO2 – CNTs modified electrode exhibited a pair of quasi-reversible peaks with a peak-to-peak separation (ΔEp) of 70.6 mV and a formal potential (E 0′) of 367.65 mV...
Magnetic labelled horseradish peroxidase-polymer nanoparticles: A recyclable nanobiocatalyst
, Article Journal of the Serbian Chemical Society ; Volume 78, Issue 7 , 2013 , Pages 921-931 ; 03525139 (ISSN) ; Vossoughi, M ; Shahrokhian, S ; Alemzadeh, I ; Sharif University of Technology
2013
Abstract
In this study, the reusability and process stability of nano-reengineered horseradish peroxidase was investigated in a fluorescence-based sensing system for hydrogen peroxide determination as a model application. To this end, dendron macromolecules were attached to the enzyme surface through bio-conjugation techniques. The resulting enzyme-polymer nanoparticles, with an average size of 14(±2) nm, showed significant life time and thermal stability. For enzyme recovery and reusability purposes, the enzyme-polymer nanoparticles were labelled with magnetic nanoparticles with a labelling yield of 90 %. These labelled enzyme molecules showed significant process stability, i.e., up to 7 recycling...
Co-Immobilization of Multi-Enzyme Cascade System into the Metal-Organic Frameworks (MOFs)for the Removal of Microcontaminants and Process Equipment Layout
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Fatolla (Supervisor) ; Yaghmaei, Soheila (Supervisor) ; Ghobadiejad, Zahra (Co-Supervisor)
Abstract
In recent years, the biodegradation of micro-contaminants using enzymes has attracted the attention of many researchers in the field of environment and health. Micro- and nano-scale environments play an important role in enzymatic catalysis that directly affects the activity and stability of enzymes. Therefore, setting a nanoscale environment for enzymes is very important, especially in liquids with undesirable properties (such as pH, temperature, toxicity, etc.) in this work, a method proposed in which the pH and the substrate concentration are regulated for enzymatic catalysis using a metal-organic framework, consisting of Glucose Oxidase (GOx) and Horseradish Peroxidase (HRP) immobilized...
Phenols removal by immobilized horseradish peroxidase
, Article Journal of Hazardous Materials ; Volume 166, Issue 2-3 , 2009 , Pages 1082-1086 ; 03043894 (ISSN) ; Nejati, S ; Sharif University of Technology
2009
Abstract
Application of immobilized horseradish peroxidase (HRP) in porous calcium alginate (ca-alginate) for the purpose of phenol removal is reported. The optimal conditions for immobilization of HRP in ca-alginate were identified. Gelation (encapsulation) was optimized at 1.0% (w/v) sodium alginate in the presence of 5.5% (w/v) of calcium chloride. Upon immobilization, pH profile of enzyme activity changes as it shows higher value at basic and acidic solution. Increasing initial phenol concentration results in a decrease in % conversion. The highest conversion belongs to phenol concentration of 2 mM. Investigation into time course of phenol removal for both encapsulated and free enzymes showed...
Immobilization of Enzymes to Nanoparticles for use in Wastewater Treatment
, M.Sc. Thesis Sharif University of Technology ; Alemzadeh, Iran (Supervisor)
Abstract
Nowadays , application of enzymes as biocatalysts in wastewater treatment processes is increasing. It is economically important to reuse enzymes and increase their stability in these types of processes. Therefore, was immobilization of enzymes and using them in wastewater treatment have a great importance.In this project, Horseradish peroxidase enzyme, whose effect on phenol removal reactions in other studies has been proven before, was immobilized on the alginate-coated magnetic nanoparticles, to investigate the effect of immobilization on the stability and function of this enzyme for phenol removal. The enzyme was immobilized at the temperature of 25 ° C and pH = 8, according to the data...
Two nanostructured polymers: Polyaniline nanofibers and new linear-dendritic matrix of poly(citric acid)-block-poly(ethylene glycol) copolymers for environmental monitoring in novel biosensors
, Article International Journal of Polymeric Materials and Polymeric Biomaterials ; Volume 62, Issue 7 , Jul , 2013 , Pages 377-383 ; 00914037 (ISSN) ; Vossoughi, M ; Alemzadeh, I ; Naeini, A. T ; Darvish, M ; Sharif University of Technology
2013
Abstract
In this work two phenol biosensors, one based on polyaniline nanofibers (PNFs) and the other based on the newly created and introduced linear-dendritic matrix of poly(citric acid)-block-poly(ethylene glycol) copolymers (PCA-PEG-PCA), were chemically modified with horseradish peroxidase (HRP) enzyme. These phenol biosensors showed an oxidation peak at 0.55 V. The amperometric response for biosensors based on PNFs showed a linear response range from 2.5 × 10-6 to 2.5 × 10-5 mol/L, with a detection limit of 2.5 M phenol. Also, the amperometric response for a biosensor based on PCA-PEG-PCA showed a linear response range from 2.5 × 10-6 to 4 × 10-5 mol/L, with a detection limit of 1.5 M phenol
Development of a novel method for determination of mercury based on its inhibitory effect on horseradish peroxidase activity followed by monitoring the surface plasmon resonance peak of gold nanoparticles
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 153 , 2016 , Pages 709-713 ; 13861425 (ISSN) ; Haji Shabani, A. M ; Dadfarnia, S ; Rohani Moghadam, M. R ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier
Abstract
A highly sensitive and simple indirect spectrophotometric method has been developed for the determination of trace amounts of inorganic mercury (Hg2 +) in aqueous media. The method is based on the inhibitory effect of Hg2 + on the activity of horseradish peroxidase (HRP) in the oxidation of ascorbic acid by hydrogen peroxide followed by the reduction of Au3 + to Au-NPs by unreacted ascorbic acid and the measurement of the absorbance of localized surface plasmon resonance (LSPR) peak of gold nanoparticles (at 530 nm) which is directly proportional to the concentration of Hg2 +. Under the optimum conditions, the calibration curve was linear in the concentration range of 1-220 ng mL- 1. Limits...
Synthesis of Nanocomposites based on Carbon nanotubes and Graphene/Ionic Liquid for Construction of Biosensors
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Ghourchian, Hedayatollah (Co-Advisor)
Abstract
In this project during 2 sections the synthesis and application of nanomaterials based on carbon nanotubes and graphene oxide for immobilization of Glucose oxide and Horseradish peroxidase enzymes for construction of effective biosensors were investigated. In section 1, we introduce a new nanomaterial in which TiO2-coated carbon nanotubes were functionalized with amine groups (NH2-TiO2-CNTs). This nanomaterial was fixed on a glassy carbon electrode surface and then its ability for direct electron transfer of Glucose oxidase (GOx) and Horseradish peroxidase (HRP) on the modified electrode was investigated. The direct electrochemistry of immobilized GOx and its electron transfer parameters at...
Synthesis and Stability Evaluation of Single Enzyme Nanoparticles for Enzymatic Based Processes
, Ph.D. Dissertation Sharif University of Technology ; Vossoughi, Manoochehr (Supervisor) ; Shahrokhian, Saeed (Co-Advisor) ; Alemzadeh, Iran (Co-Advisor)
Abstract
Enzymes, the nanometric biocatalysts that play a key role in biochemical reactions of living cells and bio-organisms, offer various applications including biosensing, bioremediation and chemical synthesis. A simple bio-conjugation procedure to surround a single horseradish peroxidase (HRP) enzyme molecule with dendritic polyester macromolecules (Polyester-32-hydroxyl-1-carboxyl bis-MPA Dendron, Generation 5) was proposed in this project. The characterization of resultant nanoparticles entitled HRP dendrozyme, was performed by TEM, DLS, GPC and FTIR spectroscopy. The results showed that HRP nanoparticles were spherical in shape and have an average size of 14 nm in diameter. Furthermore,...
Study of a Biosensor Based on Nanofibers
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Alemzadeh, Iran (Supervisor)
Abstract
In this project an enzymatic peroxidase biosensor based on two naono structured material 1-Polyaniline nananofibers 2-Polyethylene glycol-Poly citric acid copolymer was studied for phenol detection.Polyaniline nanofibers and poly ethylene glycol-poly citric acid copolymer were synthetized by chemical polymerization.Electrochemical behaviors of these biosensors were studied using cyclic voltammetry (CV) and amperometric techniques. The amperometric response of the coated electrodes is highly stable with 92% of the initial activity remaining after 5 determinations. These phenol biosensors show an oxidation peak at 0.55V. The amperometric response for phenol biosensor based on Polyaniline...
Developing Protein-Loaded Modified Hyaluronic Acid Hydrogel for Tissue Regeneration
, M.Sc. Thesis Sharif University of Technology ; Abdekhodaie, Mohammad Jafar (Supervisor)
Abstract
Growth factors play an important role in tissue repair and regeneration including articular cartilage tissue. Direct injection of growth factor is a common practice in clinics. However, it has been shown that this method is not very effective and, in some cases, induces some side effects. Moreover, incorporation of this valuable signals in systems where they are quickly released and washed out is not effective as well. Thereby the aim of this study was to design and fabricate an efficient system to effectively deliver growth factors for cartilage tissue engineering. The designed system is an injectable, in situ forming hydrogel, based on hyaluronic acid (HA) as a biocompatible and attractive...
Enzymatically crosslinked hyaluronic acid microgels as a vehicle for sustained delivery of cationic proteins
, Article European Polymer Journal ; Volume 115 , 2019 , Pages 234-243 ; 00143057 (ISSN) ; Abdekhodaie, M. J ; Mousavi, A ; Zoetebier, B ; Dijkstra, P. J ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this study, a novel biodegradable hyaluronic acid (HA) based microgel were prepared via enzymatic crosslinking of tyramine conjugated HA (HA-TA) in an inverse microemulsion. HA-TA microdroplets were crosslinked within a few seconds in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H 2 O 2 ). The high water content of the polymeric network and the inherent negative charge of the HA-TA microgels provided a suitable platform for encapsulation of cationic proteins like lysozyme and TGF-β1 growth factor. The results demonstrated that lysozyme was released, after an initial burst release, in a suitable sustained manner over a period of four weeks. Both diffusion and...
Nano reengineering of horseradish peroxidase with dendritic macromolecules for stability enhancement
, Article Enzyme and Microbial Technology ; Volume 50, Issue 1 , 2012 , Pages 10-16 ; 01410229 (ISSN) ; Vossoughi, M ; Shahrokhian, S ; Alemzadeh, I ; Sharif University of Technology
Abstract
A simple bio-conjugation procedure to surround a single horseradish peroxidase (HRP) enzyme molecule with dendritic polyester macromolecules (polyester-32-hydroxyl-1-carboxyl bis-MPA dendron, generation 5) was proposed. The characterization of resultant nanoparticles entitled HRP dendrozyme, was performed by transmission electron microscopy, dynamic light scattering, gel permeation chromatography and Fourier transform infrared spectroscopy. The results showed that HRP nanoparticles were spherical in shape and have an average size of 14 ± 2. nm in diameter. Furthermore, bio-conformational characterization of HRP dendrozyme was performed by means of circular dichroism and fluorescence...
Two-compartment processing as a tool to boost recombinant protein production
, Article Engineering in Life Sciences ; Vol. 14, issue. 2 , March , 2014 , p. 118-128 ; Herwig, C ; Sharif University of Technology
Abstract
Pichia pastoris is used extensively as a production platform for many recombinant proteins. The dissolved oxygen (DO) is one of the most important factors influencing protein production. The influence of the DO on productivity has not been studied independent from the feed rate. In this work, various DO levels were investigated independent from the feed rate. The model system was recombinant P. pastoris under the control of methanol-induced alcohol oxidase promoter, which expressed HRP as the target protein. No significant effect was observed in terms of titer and specific productivity, which is a confirmation of the fact that the DO in a one-compartment system cannot boost productivity for...
Optimization of peroxidase-catalyzed oxidative coupling process for phenol removal from wastewater using response surface methodology
, Article Environmental Science and Technology ; Volume 41, Issue 20 , 2007 , Pages 7073-7079 ; 0013936X (ISSN) ; Torabi, S. F ; Ranaei Siadat, S. O ; Jalali Heravi, M ; Ghaemi, N ; Khajeh, K ; Sharif University of Technology
2007
Abstract
Hydroxylated aromatic compounds (HACs) are considered to be primary pollutants in a wide variety of industrial wastewaters. Horseradish peroxidase (HRP) is suitable for the removal of these toxic substances. However, development of a mathematical model and optimization of the HRP-based treatment considering the economical issues by novel methods is a necessity. In the present study, optimization of phenol removal from wastewater by horseradish peroxidase (HRP) was carried out using response surface methodology (RSM) and central composite design (CCD). As the initial experimental design, 2 4-1 half-fraction factorial design (H-FFD) is accomplished in triplicate at two levels to select the...
HRP-dendron nanoparticles: The efficient biocatalyst for enzymatic polymerization of poly(2,5-dimethoxyaniline)
, Article Journal of Molecular Catalysis B: Enzymatic ; Volume 90 , June , 2013 , Pages 139-143 ; 13811177 (ISSN) ; Vossoughi, M ; Shahrokhian, S ; Alemzadeh, I ; Sharif University of Technology
2013
Abstract
Synthesis of poly(2,5-dimethoxyanilie) (PDMA) catalyzed by nano reengineered horseradish peroxidase (HRP) with dendritic macromolecules, was studied as a function of reaction media. UV-vis, gel permeation chromatography and conductivity measurements were used to explain how the reaction media compositions influence the physical properties of PDMA. Nanostructured PDMA was also synthesized by oxidative polymerization in a novel and green bi-catalyst system involving HRP and ferric chloride. FTIR and UV-vis analysis confirmed the formation of emeraldine salt state of PDMA. The thermal stability of reengineered HRP granted further studies on the polymerization using bi-catalyst system at...
Developing hyaluronic acid microgels for sustained delivery of platelet lysate for tissue engineering applications
, Article International Journal of Biological Macromolecules ; Volume 144 , 2020 , Pages 837-846 ; Abdekhodaie, M. J ; Karperien, M ; Mousavi, A ; Alvi, M ; Dijkstra, P. J ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Platelet lysate (PL), a blood product that contains high concentrations of growth factors (GFs), can be considered as a cost-effective source of multiple GFs. In this study, hyaluronic acid (HA) based microgels were developed for delivery of PL proteins. Spherical microgel were prepared using a water in oil emulsion method. First, hyaluronic acid was grafted with tyramine groups, after which prepared microdroplets were crosslinked via an enzymatic reaction in the presence of hydrogen peroxide and horseradish peroxidase. Because of electrostatic interactions, these microgels are promising carriers for positively charged proteins entrapment like most of the GFs. When microgels are incubated in...
Graphene-based nanomaterials in fighting the most challenging viruses and immunogenic disorders
, Article ACS Biomaterials Science and Engineering ; Volume 8, Issue 1 , 2022 , Pages 54-81 ; 23739878 (ISSN) ; Asadi, M ; Akhavan, O ; Sharif University of Technology
American Chemical Society
2022
Abstract
Viral diseases have long been among the biggest challenges for healthcare systems around the world. The recent Coronavirus Disease 2019 (COVID-19) pandemic is an example of how complicated the situation can get if we are not prepared to combat a viral outbreak in time, which brings up the need for quick and affordable biosensing platforms and vast knowledge of potential antiviral effects and drug/gene delivery opportunities. The same challenges have also existed for nonviral immunogenic disorders. Nanomedicine is considered a novel candidate for effectively overcoming these worldwide challenges. Among the versatile nanomaterials commonly used in biomedical applications, graphene has recently...