Cadmium isotope fractionation during leaching with nitrilotriacetic acid

Background: A simple, fast and economic analytical method for the determination of ethanol is important for clinical, biological, forensic and physico-legal purposes. Methods: Ni2+-NTA resin was used as an immobilization matrix for the simple one-step purification/ immobilization of his6-tagged ADH. Different alcohols with a concentration range of 0.5-50% V/V, namely methanol, ethanol and propanol were measured using prepared ADH enzyme thermistor. The ethanol content of Tsingtao beer was tested as a real sample containing alcohol. Reproducibility and stability of prepared ADH enzyme thermistor were also investigated by repeated measurements. Results: In comparison to the controlled pore glass (a common used support for the immobilization of enzyme) used in thermal biosensor, the use of Ni2+-NTA resin not only led to simple one-step purification/ immobilization by his6-tagged ADH binding to Ni2+-NTA resin, but also made the immobilizing supports reusable. The prepared biosensor can be used to determine ethanol and methanol by the calorimetric measurement. A linear range of 1 -32% (V/V) and 2-20% (V/V) was observed for ethanol and methanol, respectively. The detection limits were 0.3% (V/V) and 1% (V/V) for ethanol and methanol, respectively. The tested ethanol concentration of Tsingtao beer was 4.5% V/V, which is comparable with the labeled alcohol by volume (ABV) 4.80%. Conclusion: Ni2+-NTA resin, as an immobilization matrix in ET sensor, provides a simple one-step purification/immobilization for His6-tagged recombinase and a reusable immobilization matrix. The prepared biosensor exhibits good repeatability and stability. Such a new biosensor shows great promise for rapid, simple, and cost-effective analysis of ethanol and methanol, both in qualitative and in quantitative tests.

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SULFUR ISOTOPE FRACTIONATION IN BACTERIALLY AND CHEMICALLY CONTROLLED ROLL-FRONT DEPOSITS

10.1130/abs/2016am-277016 ◽

2016 ◽

Author(s):

Gretchen Hough ◽

◽

Susan M. Swapp ◽

Carol D. Frost

Keyword(s):

Isotope Fractionation ◽

Sulfur Isotope ◽

Sulfur Isotope Fractionation

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VOLCANISM DRIVEN CARBON ISOTOPE FRACTIONATION ACROSS THE WUCHIAPINGIAN-CHANGHSINGIAN BOUNDARY INTERVAL: IMPLICATIONS FROM 187OS/188OS ISOTOPE STRATIGRAPHY

10.1130/abs/2018am-316949 ◽

2018 ◽

Author(s):

Zeyang Liu ◽

◽

David Selby ◽

Hua Zhang ◽

Quanfeng Zheng ◽

...

Keyword(s):

Carbon Isotope ◽

Isotope Fractionation ◽

Carbon Isotope Fractionation ◽

Isotope Stratigraphy

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Electroanalytical chemistry of vanadium complexes: Electrochemical oxidation of [V(IV)O(nta)(H2O)]-

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19890064 ◽

1989 ◽

Vol 54 (1) ◽

pp. 64-69 ◽

Cited By ~ 4

Author(s):

Roland Meier ◽

Gerhard Werner ◽

Matthias Otto

Keyword(s):

Cyclic Voltammetry ◽

Electrochemical Oxidation ◽

Ph Dependence ◽

Differential Pulse ◽

Nitrilotriacetic Acid ◽

Reduced Form ◽

Vanadium Complexes ◽

Differential Pulse Polarography ◽

Electroanalytical Chemistry ◽

Ph Range

Electrochemical oxidation of [V(IV)O(nta)(H2O)]- (H3nta nitrilotriacetic acid) was studied in aqueous solution by means of cyclic voltammetry, differential pulse polarography, and current sampled DC polarography on mercury as electrode material. In the pH-range under study (5.5-9.0) the corresponding V(V) complex is produced by one-electron oxidation of the parent V(IV) species. The oxidation product is stable within the time scale of cyclic voltammetry. The evaluation of the pH-dependence of the half-wave potentials leads to a pKa value for [V(IV)O(nta)(H2O)]- which is in a good agreement with previous determinations. The measured value for E1/2 is very close to the formal potential E0 calculated via the Nernst equation on the basis of known literature values for log Kox and log Kred, the complex stability constants for the oxidized and reduced form, respectively.

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Temperature and its measurement

10.1093/oso/9780199551668.003.0003 ◽

2017 ◽

Author(s):

Andrew Clarke

Keyword(s):

Thermal Equilibrium ◽

Isotope Fractionation ◽

Thermodynamic Temperature ◽

The Other ◽

Deterministic Models ◽

Triple Point Of Water ◽

Temperature Scales ◽

Classical Thermodynamics ◽

The Relationship ◽

Unit Of Temperature

Temperature is that property of a body which determines whether it gains or loses energy in a particular environment. In classical thermodynamics temperature is defined by the relationship between energy and entropy. Temperature can be defined only for a body that is in thermodynamic and thermal equilibrium; whilst organisms do not conform to these criteria, the errors in assuming that they do are generally small. The Celsius and Fahrenheit temperature scales are arbitrary because they require two fixed points, one to define the zero and the other to set the scale. The thermodynamic (absolute) scale of temperature has a natural zero (absolute zero) and is defined by the triple point of water. Its unit of temperature is the Kelvin. The Celsius scale is convenient for much ecological and physiological work, but where temperature is included in statistical or deterministic models, only thermodynamic temperature should be used. Past temperatures can only be reconstructed with the use of proxies, the most important of which are based on isotope fractionation.

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Unravelling the process of petroleum hydrocarbon biodegradation in different filter materials of constructed wetlands by stable isotope fractionation and labelling studies

Biodegradation ◽

10.1007/s10532-021-09942-1 ◽

2021 ◽

Author(s):

Andrea Watzinger ◽

Melanie Hager ◽

Thomas Reichenauer ◽

Gerhard Soja ◽

Paul Kinner

Keyword(s):

Stable Isotope ◽

Constructed Wetlands ◽

Hydrogen Isotope ◽

Petroleum Hydrocarbon ◽

Isotope Fractionation ◽

Isotope Effects ◽

Filter Material ◽

Hydrocarbon Biodegradation ◽

Stable Isotope Fractionation ◽

Filter Materials

AbstractMaintaining and supporting complete biodegradation during remediation of petroleum hydrocarbon contaminated groundwater in constructed wetlands is vital for the final destruction and removal of contaminants. We aimed to compare and gain insight into biodegradation and explore possible limitations in different filter materials (sand, sand amended with biochar, expanded clay). These filters were collected from constructed wetlands after two years of operation and batch experiments were conducted using two stable isotope techniques; (i) carbon isotope labelling of hexadecane and (ii) hydrogen isotope fractionation of decane. Both hydrocarbon compounds hexadecane and decane were biodegraded. The mineralization rate of hexadecane was higher in the sandy filter material (3.6 µg CO2 g−1 day−1) than in the expanded clay (1.0 µg CO2 g−1 day−1). The microbial community of the constructed wetland microcosms was dominated by Gram negative bacteria and fungi and was specific for the different filter materials while hexadecane was primarily anabolized by bacteria. Adsorption / desorption of petroleum hydrocarbons in expanded clay was observed, which might not hinder but delay biodegradation. Very few cases of hydrogen isotope fractionation were recorded in expanded clay and sand & biochar filters during decane biodegradation. In sand filters, decane was biodegraded more slowly and hydrogen isotope fractionation was visible. Still, the range of observed apparent kinetic hydrogen isotope effects (AKIEH = 1.072–1.500) and apparent decane biodegradation rates (k = − 0.017 to − 0.067 day−1) of the sand filter were low. To conclude, low biodegradation rates, small hydrogen isotope fractionation, zero order mineralization kinetics and lack of microbial biomass growth indicated that mass transfer controlled biodegradation.

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Novel Regeneration Approach for Creating Reusable FO-SPR Probes with NTA Surface Chemistry

Nanomaterials ◽

10.3390/nano11010186 ◽

2021 ◽

Vol 11 (1) ◽

pp. 186

Author(s):

Jia-Huan Qu ◽

Karen Leirs ◽

Remei Escudero ◽

Žiga Strmšek ◽

Roman Jerala ◽

...

Keyword(s):

Surface Chemistry ◽

Fluorescent Protein ◽

Cost Effective ◽

Nitrilotriacetic Acid ◽

Antibody Fragments ◽

Rapid Screening ◽

Red Fluorescent Protein ◽

Effective Manner ◽

Surface Regeneration ◽

Sensitivity Specificity

To date, surface plasmon resonance (SPR) biosensors have been exploited in numerous different contexts while continuously pushing boundaries in terms of improved sensitivity, specificity, portability and reusability. The latter has attracted attention as a viable alternative to disposable biosensors, also offering prospects for rapid screening of biomolecules or biomolecular interactions. In this context here, we developed an approach to successfully regenerate a fiber-optic (FO)-SPR surface when utilizing cobalt (II)-nitrilotriacetic acid (NTA) surface chemistry. To achieve this, we tested multiple regeneration conditions that can disrupt the NTA chelate on a surface fully saturated with His6-tagged antibody fragments (scFv-33H1F7) over ten regeneration cycles. The best surface regeneration was obtained when combining 100 mM EDTA, 500 mM imidazole and 0.5% SDS at pH 8.0 for 1 min with shaking at 150 rpm followed by washing with 0.5 M NaOH for 3 min. The true versatility of the established approach was proven by regenerating the NTA surface for ten cycles with three other model system bioreceptors, different in their size and structure: His6-tagged SARS-CoV-2 spike fragment (receptor binding domain, RBD), a red fluorescent protein (RFP) and protein origami carrying 4 RFPs (Tet12SN-RRRR). Enabling the removal of His6-tagged bioreceptors from NTA surfaces in a fast and cost-effective manner can have broad applications, spanning from the development of biosensors and various biopharmaceutical analyses to the synthesis of novel biomaterials.

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Removal of Impurities from Shungite Via a Combination of Physical and Chemical Treatments

Minerals ◽

10.3390/min11030245 ◽

2021 ◽

Vol 11 (3) ◽

pp. 245

Author(s):

Toyohisa Fujita ◽

Taichi Aoki ◽

Josiane Ponou ◽

Gjergj Dodbiba ◽

Chunlin He ◽

...

Keyword(s):

Magnetic Separation ◽

Sulfur Removal ◽

Nitrilotriacetic Acid ◽

Microwave Treatment ◽

Magnetic Flux Density ◽

High Gradient Magnetic Separation ◽

Chemical Leaching ◽

Inorganic Acids ◽

Mineralogical Study ◽

Physical And Chemical

This study investigated the removal of sulfur and iron from shungite rocks through different methods after fine grinding: flotation, magnetic separation, microwave treatment, and chemical leaching. In this work, first, a mineralogical study of shungite was conducted. The carbon, silica, iron, and sulfur compositions in the as-received shungite were 45.4%, 38.3%, 4.6%, and 2.4%, respectively. In flotation, a sulfur grade of 1.4% was obtained. In the wet high-gradient magnetic separation at a magnetic flux density of 1 tesla, the iron and sulfur grades in the nonmagnetic fraction were 2.8% and 1.9%, respectively. Furthermore, the sulfur reduced to 0.2% by the 9 min microwave irradiation. In addition, chemical leaching using chelating reagents and inorganic acids was utilized to remove iron and sulfur. Nitrilotriacetic acid (NTA) could reduce the iron and sulfur grades to 2.0% and 0.9%, respectively. For leaching using reverse aqua regia, the iron and sulfur grades were reduced to 0.9% and 0.23%, respectively. For leaching using a 6N HCl with H2O2 aqueous solution, the iron and sulfur grades were reduced to 0.8% and 0.34%, respectively. Overall, chemical leaching using HCl with H2O2 was the most effective for iron and sulfur removal from shungite.

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