Enzyme immobilization on a low-cost magnetic support: Kinetic studies on immobilized and coimmobilized glucose oxidase and glucoamylase

Dyes contain carcinogenic materials which can cause serious hazards to aquatic life and the users of water. Textile industry is the main source of dye wastewater which results in environmental pollution. Many studies have been conducted to investigate the use of low cost adsorbent as an alternative technique for the adsorption of dye. The objective of this study is to determine the potential of eggshell powder as an adsorbent for methylene blue removal and find out the best operating conditions for the color adsorption at laboratory scale. The adsorption of cationic methylene blue from aqueous solution onto the eggshell powder was carried out by varying the operating parameters which were contact time, pH, dosage of eggshell powder and temperature in order to study their effect in adsorption capacity of eggshell powder. The results obtained showed that the best operating condition for removal of methylene blue was at pH 10 (78.98 %) and temperature 50°C (47.37 %) by using 2 g of eggshell powder (57.03 %) with 30 minutes equilibrium time (41.36 %). The kinetic studies indicated that pseudo-second-order model best described the adsorption process.

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Organic Dyes Adsorption on the Almond Shell (Prunus dulcis) as Agricultural Solid Waste from Aqueous Solution in Single and Binary Mixture Systems

Biointerface Research in Applied Chemistry ◽

10.33263/briac122.20222040 ◽

2021 ◽

Vol 12 (2) ◽

pp. 2022-2040

Keyword(s):

Aqueous Solution ◽

Binary Mixture ◽

Contact Time ◽

Binary Systems ◽

Organic Dyes ◽

Low Cost ◽

Kinetic Studies ◽

Prunus Dulcis ◽

Order Kinetic ◽

Almond Shell

Almond shell (AS) is a low-cost adsorbent used in this study for the removal of methylene blue (MB), crystal violet (CV), and Congo red (CR) from an aqueous solution in single and mixture binary systems. The low-cost adsorbent was characterized by FTIR and SEM analysis. The effects of AS dose, contact time, initial dye concentration, pH, and temperature on MB, CV, and CR adsorption were studied in a single system. In a binary system, the MB, CV, and CR were removed from the mixture of MB+CR, CV+MB, and CV+CR with a percentage in volume ranging from 0 to 100 % in MB and CV, and CR. Kinetic studies showed rapid sorption following a second-order kinetic model with of contact time of 10 min. The modulation of adsorption isotherms showed that retention follows the Langmuir model. The thermodynamic parameters proved that the MB, CV, and CR adsorption process was feasible, spontaneous, and exothermic. The synergy adsorption between dyes in a binary mixture of MB+CR and CV+CR, while the competition adsorption between dyes in a binary mixture of MB+ CV.

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A Self-Powered Biosensor for the Detection of Glutathione

Biosensors ◽

10.3390/bios10090114 ◽

2020 ◽

Vol 10 (9) ◽

pp. 114 ◽

Cited By ~ 2

Author(s):

Brandon G. Roy ◽

Julia L. Rutherford ◽

Anna E. Weaver ◽

Kevin Beaver ◽

Michelle Rasmussen

Keyword(s):

Detection Limit ◽

Glucose Oxidase ◽

Power Output ◽

Low Cost ◽

Linear Range ◽

Biofuel Cell ◽

Bilirubin Oxidase ◽

Biological Molecule ◽

Enzymatic Biofuel Cell ◽

Self Powered

Glutathione is an important biological molecule which can be an indicator of numerous diseases. A method for self-powered detection of glutathione levels in solution has been developed using an enzymatic biofuel cell. The device consists of a glucose oxidase anode and a bilirubin oxidase cathode. For the detection of glutathione, the inhibition of bilirubin oxidase leads to a measurable decrease in current and power output. The reported method has a detection limit of 0.043 mM and a linear range up to 1.7 mM. Being able to detect a range of concentrations can be useful in evaluating a patient’s health. This method has the potential to be implemented as a quick, low-cost alternative to previously reported methods.

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An alternative low-cost adsorbent for gold recovery from cyanide-leached liquors: Adsorption isotherm and kinetic studies

Adsorption Science & Technology ◽

10.1177/0263617418802557 ◽

2018 ◽

Vol 37 (1-2) ◽

pp. 3-23 ◽

Cited By ~ 5

Author(s):

Refiloe Tsolele ◽

Fanyana Moses Mtunzi ◽

Michael John Klink ◽

Vusumzi Emmanuel Pakade

Keyword(s):

Activated Carbons ◽

Selective Adsorption ◽

Low Cost ◽

Kinetic Studies ◽

Agitation Speed ◽

Gold Recovery ◽

Attractive Alternative ◽

Solution Ph ◽

Initial Concentration ◽

Modified Activated Carbons

Pristine Macadamia nutshell-based activated carbons were chemically oxidized with different concentrations of H3PO4 and HNO3 to increase their surface adsorption properties and further explore if they could be an attractive alternative low-cost adsorbent for gold recovery from cyanide-leached liquors. The modified activated carbons were labeled MACN20, MACN40 and MACN55 to signify the materials prepared from 20%, 40% and 55% (v/v) HNO3, respectively. Similar nomenclature was followed for H3PO4-modified activated carbons. Brunauer-Emmet-Teller, scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, elemental analysis and X-ray diffraction spectroscopy were used to characterize the prepared activated carbons. The physical properties were attained through determining attrition, ash content, volatile matter and moisture content of all the activated carbons. Various parameters that affect selective adsorption such as the effect of initial concentration, time, agitation speed, interfering species and the dose of the adsorbent were investigated. Optimal parameters for gold ion adsorption were as follows: solution pH, 10; contact time, 6 h; agitation speed, 150 r/min; sorbent amount, 4 g and initial concentration, 5.5 mg/L. The observed selectivity order was not the same for all the adsorbents, but the adsorption of gold was found to be mostly influenced in the presence of nickel and least influenced by copper. MACN55 was found to be the most efficient adsorbent with 74% of gold adsorption from a real-world sample and displayed a similar performance to coconut-based activated carbons.

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Brilliant Green and Acid Orange 74 Dyes Removal from Water by Pinus roxburghii Leaves in Naturally Benign Way: An Application of Green Chemistry

Journal of Chemistry ◽

10.1155/2019/3573704 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Rabia Rehman ◽

Sara Jan Muhammad ◽

Muhammad Arshad

Keyword(s):

Brilliant Green ◽

Low Cost ◽

Kinetic Studies ◽

Agitation Speed ◽

Pinus Roxburghii ◽

Acid Orange ◽

Pseudo Second Order ◽

Optimized Conditions ◽

Adsorbent Dose ◽

Dyes Removal

The purpose of this study was to use low cost and easily accessible biosorbent for batch-scale elimination of brilliant green and acid orange 74 dyes from aqueous solution. Pinus roxburghii leaves were utilized to study their dye-eliminating capacities. The adsorbent was characterized by FTIR, TGA, DTA, and SEM. The optimized conditions for brilliant green and acid orange 74 dye elimination were adsorbent dose, 1.2 and 1.8 g; contact time, 30 and 45 min; pH, 2 and 1; temperature, 50°C and 60°C; and agitation speed, 125 rpm and 50 rpm for BG and AO-74, respectively. Adsorption records well fitted Langmuir isotherm. Possibility of the procedure was shown by negative values of the thermodynamic parameter ∆G° for both dyes. Kinetic studies showed that adsorption of BG and AO-74 dyes from watery solution by PR leaves followed pseudo-second-order kinetics.

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Single- and coupled-enzyme nylon-tube reactors for plasma glucose determination with glucose oxidase and aldehyde dehydrogenase.

Clinical Chemistry ◽

10.1093/clinchem/26.12.1652 ◽

1980 ◽

Vol 26 (12) ◽

pp. 1652-1655 ◽

Cited By ~ 8

Author(s):

W Hinsch ◽

A Antonijewić ◽

P V Sundaram

Keyword(s):

Glucose Oxidase ◽

Aldehyde Dehydrogenase ◽

Plasma Glucose ◽

Continuous Flow ◽

Flow System ◽

Low Cost ◽

Immobilized Enzymes ◽

Glucose Determination ◽

Nylon Tube

Abstract We describe routine methods for determining glucose in plasma with use of aldehyde dehydrogenase or glucose oxidase-aldehyde dehydrogenase immobilized in a nylon tube that is integrated into a continuous-flow system. Although the coupled-enzyme nylon-tube reactors require the presence of a third enzyme, catalase, in solution, the kinetics are not so complicated as to preclude reliable routine determination of glucose at very low cost. Precision is good, and results correlate well with those by the method involving glucose oxidase in solution. More than 3000 tests may be carried out with one reactor. The immobilized enzymes are stable for several months at 4 degrees C when not in use.

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