Enzyme Immobilization on Polyethyleneimine- Coated Magnetite Particles

The enzyme-containing magnetic composites are presented. The magnetic matrix for enzyme immobilization is obtained by sequential application of an amine-containing polysaccharide—chitosan and a synthetic polymer—poly(ethylene-alt-maleic acid) to the magnetite microparticles to form the interpolyelectrolyte complex shell. Then, the enzyme (trypsin) is immobilized by covalent or noncovalent binding. Thus, the suggested composites can be readily obtained in the environmentally friendly manner. The enzyme capacity of the resulting composites reaches 28.0–32.6 mg/g. The maximum hydrolysis rates of the H-Val-Leu-Lys-pNA substrate provided by these composites range within 0.60·10–7–0.77·10–7 M/min.

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A New Method for Direct Determination of the Recoilless Fraction with Application to Magnetic Nanoparticles

MRS Proceedings ◽

10.1557/proc-721-e3.7 ◽

2002 ◽

Vol 721 ◽

Author(s):

Monica Sorescu

Keyword(s):

Room Temperature ◽

Average Particle Size ◽

Direct Determination ◽

Average Particle ◽

Lattice Method ◽

Recoilless Fraction ◽

Single Room ◽

Magnetite Particles ◽

Physical Mixtures

AbstractWe propose a two-lattice method for direct determination of the recoilless fraction using a single room-temperature transmission Mössbauer measurement. The method is first demonstrated for the case of iron and metallic glass two-foil system and is next generalized for the case of physical mixtures of two powders. We further apply this method to determine the recoilless fraction of hematite and magnetite particles. Finally, we provide direct measurement of the recoilless fraction in nanohematite and nanomagnetite with an average particle size of 19 nm.

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Tuning the Magnetic Vortex State in Magnetite Nanodiscs for Remote Control of Biological Signalling

10.26434/chemrxiv.10299506.v1 ◽

2019 ◽

Author(s):

Danijela Gregurec ◽

Alexander W. Senko ◽

Andrey Chuvilin ◽

Pooja Reddy ◽

Ashwin Sankararaman ◽

...

Keyword(s):

Remote Control ◽

Ion Channels ◽

Ground State ◽

Magnetic Particles ◽

Colloidal Stability ◽

Vortex State ◽

Magnetic Vortex ◽

Electron Holography ◽

Dipole Interactions ◽

Magnetite Particles

In this work, we demonstrate the application of anisotropic magnetite nanodiscs (MNDs) as transducers of torque to mechanosensory cells under weak, slowly varying magnetic fields (MFs). These MNDs possess a ground state vortex configuration of magnetic spins which affords greater colloidal stability due to eliminated dipole-dipole interactions characteristic of isotropic magnetic particles of similar size. We first predict vortex magnetization using micromagnetic stimulations in sub-micron anisotropic magnetite particles and then use electron holography to experimentally investigate the magnetization of MNDs 98–226 nm in diameter. When MNDs are coupled to MFs, they transition between vortex and in-plane magnetization allowing for the exertion of the torque on the pN scale, which is sufficient to activate mechanosensitive ion channels in cell membranes.<br>

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Biocatalytic Ketone Reductions Using Biobeads

10.26434/chemrxiv.12722030.v1 ◽

2020 ◽

Author(s):

Jia Shen Chew ◽

Ken Chi Lik Lee ◽

THI THANH NHA HO

Keyword(s):

Enzyme Immobilization ◽

High Throughput ◽

High Throughput Screening ◽

Chiral Hplc ◽

Micro Scale

<p>Lee and coworkers offers a kind of new concept to enzyme immobilization and explores its suitability in the context of miniaturisation and high-throughput screening. Here, polystyrene-immobilized ketoreductases are compared with its non-immobilized counterparts in terms of conversion and stereoselectivity (both determined by chiral HPLC), and the study indicates that the BioBeads perform similarly (sometimes slightly more selective) which may be useful whenever defined micro-scale amounts of biocatalysts were required in high-throughput experiment settings.</p>

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Faculty Opinions recommendation of Metal-Organic Frameworks: A New Platform for Enzyme Immobilization.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.737756041.793576012 ◽

2020 ◽

Author(s):

Jon Zubieta

Keyword(s):

Enzyme Immobilization ◽

Metal Organic Frameworks ◽

Metal Organic

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Enzyme Immobilization on Nanomaterials for Biosensor and Biocatalyst in Food and Biomedical Industry

Current Pharmaceutical Design ◽

10.2174/1381612825666190712181403 ◽

2019 ◽

Vol 25 (24) ◽

pp. 2661-2676 ◽

Cited By ~ 1

Author(s):

Sundaresan Bhavaniramya ◽

Ramar Vanajothi ◽

Selvaraju Vishnupriya ◽

Kumpati Premkumar ◽

Mohammad S. Al-Aboody ◽

...

Keyword(s):

Enzyme Activity ◽

Enzyme Immobilization ◽

Food Industry ◽

Environmental Changes ◽

Immobilized Enzymes ◽

Food Industries ◽

Physiological Processes ◽

Different Types ◽

Simple Processing ◽

Biomedical Industry

Enzymes exhibit a great catalytic activity for several physiological processes. Utilization of immobilized enzymes has a great potential in several food industries due to their excellent functional properties, simple processing and cost effectiveness during the past decades. Though they have several applications, they still exhibit some challenges. To overcome the challenges, nanoparticles with their unique physicochemical properties act as very attractive carriers for enzyme immobilization. The enzyme immobilization method is not only widely used in the food industry but is also a component methodology in the pharmaceutical industry. Compared to the free enzymes, immobilized forms are more robust and resistant to environmental changes. In this method, the mobility of enzymes is artificially restricted to changing their structure and properties. Due to their sensitive nature, the classical immobilization methods are still limited as a result of the reduction of enzyme activity. In order to improve the enzyme activity and their properties, nanomaterials are used as a carrier for enzyme immobilization. Recently, much attention has been directed towards the research on the potentiality of the immobilized enzymes in the food industry. Hence, the present review emphasizes the different types of immobilization methods that is presently used in the food industry and other applications. Various types of nanomaterials such as nanofibers, nanoflowers and magnetic nanoparticles are significantly used as a support material in the immobilization methods. However, several numbers of immobilized enzymes are used in the food industries to improve the processing methods which not only reduce the production cost but also the effluents from the industry.

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Sorption of Water Soluble Organic Dyes on Magnetic Poly(oxy-2,6-dimethyl-1,4-phenylene)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19951448 ◽

1995 ◽

Vol 60 (9) ◽

pp. 1448-1456 ◽

Cited By ~ 36

Author(s):

Ivo Šafařík ◽

Miroslava Šafaříková ◽

Vlasta Buřičová

Keyword(s):

Organic Compounds ◽

Azo Dye ◽

Organic Dyes ◽

Water Soluble ◽

Magnetic Composite ◽

Water Solutions ◽

Magnetite Particles

Magnetic composite based on poly(oxy-2,6-dimethyl-1,4-phenylene) (PODMP) was prepared by melting the polymer with ε-caprolactam in a presence of fine magnetite particles. Magnetic PODMP was used for sorption of water soluble organic compounds (dyes belonging to triphenylmethane, heteropolycyclic and azo dye groups) from water solutions. There were considerable differences in the binding of the dyes tested. In general, heteropolycyclic dyes exhibited the lowest sorption.

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α-Cellulose Fibers of Paper-Waste Origin Surface-Modified with Fe3O4 and Thiolated-Chitosan for Efficacious Immobilization of Laccase

Polymers ◽

10.3390/polym13040581 ◽

2021 ◽

Vol 13 (4) ◽

pp. 581

Author(s):

Gajanan S. Ghodake ◽

Surendra K. Shinde ◽

Ganesh D. Saratale ◽

Rijuta G. Saratale ◽

Min Kim ◽

...

Keyword(s):

Enzyme Immobilization ◽

Photoelectron Spectroscopy ◽

Cellulose Fibers ◽

Relative Activity ◽

Significant Activity ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Laccase Immobilization ◽

Surface Modified

The utilization of waste-paper-biomass for extraction of important α-cellulose biopolymer, and modification of extracted α-cellulose for application in enzyme immobilization can be extremely vital for green circular bio-economy. Thus, in this study, α-cellulose fibers were super-magnetized (Fe3O4), grafted with chitosan (CTNs), and thiol (-SH) modified for laccase immobilization. The developed material was characterized by high-resolution transmission electron microscopy (HR-TEM), HR-TEM energy dispersive X-ray spectroscopy (HR-TEM-EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) analyses. Laccase immobilized on α-Cellulose-Fe3O4-CTNs (α-Cellulose-Fe3O4-CTNs-Laccase) gave significant activity recovery (99.16%) and laccase loading potential (169.36 mg/g). The α-Cellulose-Fe3O4-CTNs-Laccase displayed excellent stabilities for temperature, pH, and storage time. The α-Cellulose-Fe3O4-CTNs-Laccase applied in repeated cycles shown remarkable consistency of activity retention for 10 cycles. After the 10th cycle, α-Cellulose-Fe3O4-CTNs possessed 80.65% relative activity. Furthermore, α-Cellulose-Fe3O4-CTNs-Laccase shown excellent degradation of pharmaceutical contaminant sulfamethoxazole (SMX). The SMX degradation by α-Cellulose-Fe3O4-CTNs-Laccase was found optimum at incubation time (20 h), pH (3), temperatures (30 °C), and shaking conditions (200 rpm). Finally, α-Cellulose-Fe3O4-CTNs-Laccase gave repeated degradation of SMX. Thus, this study presents a novel, waste-derived, highly capable, and super-magnetic nanocomposite for enzyme immobilization applications.

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Functionalized Materials as a Versatile Platform for Enzyme Immobilization in Wastewater Treatment

Current Pollution Reports ◽

10.1007/s40726-021-00193-5 ◽

2021 ◽

Author(s):

Agnieszka Kołodziejczak-Radzimska ◽

Long D. Nghiem ◽

Teofil Jesionowski

Keyword(s):

Wastewater Treatment ◽

Enzyme Immobilization ◽

Organic Dyes ◽

Scientific Progress ◽

Immobilized Enzymes ◽

Chemical Oxidation ◽

Biologically Active ◽

Water Pollutants ◽

Untreated Wastewater ◽

Functionalized Materials

Abstract Purpose of Review Untreated wastewater discharge can significantly and negatively impact the state of the environment. Rapid industrialization and economic development have directly contributed to land and water pollution resulting from the application of many chemicals such as organic dyes, pharmaceuticals, and industrial reagents. The removal of these chemicals before effluent discharge is crucial for environmental protection. This review aims to explore the importance of functionalized materials in the preparation of biocatalytic systems and consider their application in eliminating water pollutants. Recent Findings Wastewater treatment methods can be classified into three groups: (i) chemical (e.g., chemical oxidation and ozonation), (ii) physical (e.g., membrane separation and ion exchange), and (iii) biological processes. Biological treatment is the most widely used method due to its cost-effectiveness and eco-friendliness. In particular, the use of immobilized enzymes has recently become more attractive as a result of scientific progress in advanced material synthesis. The selection of an appropriate support plays an important role in the preparation of such biologically active systems. Recent studies have demonstrated the use of various materials for enzyme immobilization in the purification of water. Summary This review identifies and discusses different biocatalytic systems used in the enzymatic degradation of various water pollutants. Materials functionalized by specific groups can serve as good support matrices for enzyme immobilization, providing chemical and thermal stability to support catalytic reactions. Enzymatic biocatalysis converts the pollutants into simpler products, which are usually less toxic than their parents. Due to immobilization, the enzyme can be used over multiple cycles to reduce the cost of wastewater treatment. Future studies in this field should focus on developing new platforms for enzyme immobilization in order to improve degradation efficiency.

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