ESR experiments were performed at room temperature with a Bruker ESP300E spectrometer operating at X-band frequency (9.54 GHz). The microwave power was set to 20 mW and the magnetic field modulation frequency and amplitude to 100 kHz and 1 mT, respectively. The spectral resolution was 0.7 mT/pt and the acquisition time was 30 min for each sample. After weighing, each aorta sample was carefully digested in HNO3 (65%) under a flame. Digestion was repeated 3 times to ensure the sample’s complete mineralization. After the last addition of HNO3, 100 mg of NaNO3 salt was added to obtain a homogeneous solid powder for the ESR analysis. The recorded ESR spectra were normalized to the aorta mass (expressed in g), and their intensity (obtained by double-integration of the first derivative absorption curve) was compared with that of reference samples with a known concentration of Fe2O3 nanoparticles (ranging from 5 × 10−10 to 1 × 10−7 mol/g).
Esp 300e spectrometer
Manufactured by Bruker
Sourced in Germany
The ESP 300E spectrometer is a compact and versatile electron spin resonance (ESR) or electron paramagnetic resonance (EPR) spectrometer designed for a wide range of applications. It features a stable, high-performance magnet system and a sensitive microwave bridge to enable accurate measurements of samples with a variety of paramagnetic centers.
Automatically generated - may contain errors
Lab products found in correlation
Matlab, by MathWorks (2 mentions)
Er4102st, by Bruker (2 mentions)
Su8100, by Thermo Fisher Scientific (1 mentions)
Asap 2020 system, by Micrometrics (1 mentions)
Tecnai f20, by Thermo Fisher Scientific (1 mentions)
X pert, by Malvern Panalytical (1 mentions)
Easyspin, by MathWorks (1 mentions)
Er035m nmr gaussmeter, by Bruker (1 mentions)
Uv 2001 spectrophotometer, by Shimadzu (1 mentions)
Spectrum 100 ftir spectrometer, by PerkinElmer (1 mentions)
Invia raman microscope, by Renishaw (1 mentions)
Microflex lt, by Bruker (1 mentions)
Nicolet avatar 330 ftir spectrometer, by Thermo Fisher Scientific (1 mentions)
16 protocols using esp 300e spectrometer
1
Quantifying Iron Oxide Nanoparticles in Aortic Tissue
2
Characterization of Nanostructured Materials
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The compositions and phases of the obtained samples were characterized by powder XRD on the PANalytical X’Pert diffractometer with a CuKα radiation. SEM (SU8100) and HRTEM (FEI Tecnai-F20) were used to characterize the shape and crystal structure. The surface compositions of samples were characterized by PHI QUANTUM2000 photoelectron spectrometer (XPS). N2 adsorption/desorption isotherms were used to characterize the surface areas of samples based on the BET method (Micrometrics ASAP 2020 system). Bruker ESP-300E spectrometer was used to measure EPR spectra at 9.8 GHz with X-band and 100 Hz field modulation. Dynamic light scattering (DLS) experiments were conducted on a Nano-Zetasizer (Nano-ZS) from Malvern Instruments (Malvern, UK). The experimental process was as follows: samples (0.1 g) and ethanol (10 mL) were added into a glass bottle (15 mL) and dispersed uniformly by ultrasonication for 10 min. Solutions were placed at different times under agitation and non-agitation, respectively. Then, the upper liquids were taken for DLS tests.
3
EPR Spectroscopy of Fenton Reactions
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The amount of HLS required
for each experimental
condition was dissolved in Milli-Q water, and the pH was adjusted
to 4.5. Then, the iron salt was dissolved to reach a concentration
of 5 mg/L of Fe(II) or Fe(III). The pH was carefully adjusted to 5
by dropwise addition of hydrochloric acid or sodium hydroxide; then,
DMPO (17 mM) was added to the sample and finally hydrogen peroxide
(1 mM) was also added. Once hydrogen peroxide is present in the solution,
the reaction starts, and therefore it was the last reactive species
added to minimize the time between the addition of all reagents and
the EPR measurements.
EPR spectra were acquired at room temperature
with a Bruker ESP300E spectrometer. Measurements were carried out
in quartz capillary tubes. The following parameters were set: the
microwave frequency was 9.78 GHz, and the power was 5 mW; the modulation
frequency was 100 kHz with an amplitude of 0.4 Gauss; and the time
constant was 40 ms. For the Fe(III) experiments, 10 scans were accumulated
(this was not necessary in Fe(II) measurements because of the high
intensity of the signal). The intensity was determined by an average
of the height of the two central lines of the DMPO-OH spectrum, and
then the value was normalized.
for each experimental
condition was dissolved in Milli-Q water, and the pH was adjusted
to 4.5. Then, the iron salt was dissolved to reach a concentration
of 5 mg/L of Fe(II) or Fe(III). The pH was carefully adjusted to 5
by dropwise addition of hydrochloric acid or sodium hydroxide; then,
DMPO (17 mM) was added to the sample and finally hydrogen peroxide
(1 mM) was also added. Once hydrogen peroxide is present in the solution,
the reaction starts, and therefore it was the last reactive species
added to minimize the time between the addition of all reagents and
the EPR measurements.
EPR spectra were acquired at room temperature
with a Bruker ESP300E spectrometer. Measurements were carried out
in quartz capillary tubes. The following parameters were set: the
microwave frequency was 9.78 GHz, and the power was 5 mW; the modulation
frequency was 100 kHz with an amplitude of 0.4 Gauss; and the time
constant was 40 ms. For the Fe(III) experiments, 10 scans were accumulated
(this was not necessary in Fe(II) measurements because of the high
intensity of the signal). The intensity was determined by an average
of the height of the two central lines of the DMPO-OH spectrum, and
then the value was normalized.
4
EPR Spectroscopy of Molecular Samples
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The EPR spectra were estimated on the Bruker ESP 300 E spectrometer (Rheinstetten, Germany) at room temperature, operating at a microwave frequency of 9.73 GHz. The instrumental settings were as follows: the microwave power was 10 mW, the center field was set at 3480 G, with a 100 kHz modulation frequency and a range of 80 G, a modulation amplitude of 1.01 G, and a time scan of 256 s.
5
Probing Oxygen Reduction Pathways
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as spin trapping reagent, the reduction pathways of O2 on different catalysts were determined by in situ electron spin resonance (ESR) analysis. An ESP 300E spectrometer (Bruker, Switzerland) was used to detect the ESR signals of radicals trapped by DMPO. Generally, the catalyst (1 mg) was put into a mixture containing 1 mL alcohol/water (4 wt%) and 0.125 mmol DMPO. After passing the O2 for 3 min, the sample was irradiated under UV light for 5 min before testing.
6
EPR Spectroscopic Studies of Protein
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
For EPR spectroscopic studies, 500 μm protein was prepared in 50 mm phosphate buffer, pH 7.0. In all cases, 30% glycerol was added as a cryoprotectant. Typically, 100 μl was inserted in a quartz EPR tube and flash-frozen in liquid N2. In addition, the WT protein was activated by adding a 5-fold molar excess of H2O2 to generate Compound I. The EPR sample tubes were vacuum-pumped to 1 millibar during the experiments to remove excess of paramagnetic dioxygen. X-band CW EPR experiments were performed on a Bruker ESP300E spectrometer operating at a microwave frequency of ∼9.44 GHz equipped with a liquid-helium cryostat (Oxford Inc.) to enable temperatures from 2.5 K up to room temperature. Calibration of the magnetic field was done using a Bruker ER035M NMR gaussmeter.
All spectra of the ferric proteins were recorded at 4 K under nonsaturating conditions at 1-milliwatt microwave power and 0.5-mT modulation amplitude. The detailed EPR spectrum of the organic radical in the resting state protein was recorded at 80 K using 0.1-milliwatt microwave power and 1-mT modulation amplitude. The EPR spectrum of compound I was recorded at 2.5 K using 100-microwatt microwave power and 0.1-mT modulation amplitude. In all cases, the modulation frequency was 100 kHz. Simulation of the experimental spectra was done using the Matlab (MathWorks, Natick, MA)-based software Easyspin (49 (link)).
All spectra of the ferric proteins were recorded at 4 K under nonsaturating conditions at 1-milliwatt microwave power and 0.5-mT modulation amplitude. The detailed EPR spectrum of the organic radical in the resting state protein was recorded at 80 K using 0.1-milliwatt microwave power and 1-mT modulation amplitude. The EPR spectrum of compound I was recorded at 2.5 K using 100-microwatt microwave power and 0.1-mT modulation amplitude. In all cases, the modulation frequency was 100 kHz. Simulation of the experimental spectra was done using the Matlab (MathWorks, Natick, MA)-based software Easyspin (49 (link)).
7
Quantification of Free Radicals by EPR
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
EPR spectra were recorded using a quartz flat cell at room temperature with a Bruker ESP 300E spectrometer operating at X-band with 100 kHz modulation frequency and a TM110 cavity. The instrument settings were as follows: microwave frequency of 9.779 GHz, modulation amplitude of 0.5 G, microwave power of 20 mW, scan time of 30 s, time constant of 82 ms, and a single scan. EPR spectral recording began two minutes after the addition of H2O2. All the experiments were carried out in phosphate buffer (50 mM and pH 7.4) containing 0.1 mM DTPA. Reactions were initiated by the addition of H2O2. Quantitation of the observed free radical signals was performed by computer simulation of the spectra with comparison of the double integral of the observed signal to that of a TEMPO standard (1 μM) measured under the identical conditions [47] (link).
8
Quantitative EPR Analysis of Free Radicals
9
Multi-spectroscopic Characterization Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
FT-IR spectra were recorded between 4000 and 650 cm -1 using a PerkinElmer Spectrum 100 FT-IR spectrometer. Mass spectra were measured on a MALDI (matrix assisted laser desorption ionization) BRUKER Microflex LT (Bremen, Germany) using 1,8,9-anthracenetriol or 2,5-dihydroxybenzoic acid as the matrix. UV-visible electronic absorption spectra were recorded on a Shimadzu 2001 UV spectrophotometer. Raman spectroscopy was conducted employing a Renishaw inVia Raman microscope with a 473 nm laser. ESR spectra were recorded at 77 K on a Bruker ESP 300E spectrometer, using a standard rectangular (TE102) ESR cavity (Bruker ER4102ST). Microwave power of 1.6 mW and modulation amplitude 1 G were used.
10
EPR Spectroscopy Optimization Protocol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
EPR spectra were recorded at room
temperature on a Bruker ESP 300 E spectrometer provided with a T102
rectangular cavity that works with an X band (9.5 GHz). The signal-to-noise
ratio of spectra was increased by accumulation of scans using the
F/Flock accessory to guarantee large field reproducibility. Precautions
to avoid undesirable spectral distortion and line broadenings, such
as those arising from microwave power saturation and magnetic field
overmodulation, were also taken into account to improve sensitivity.
temperature on a Bruker ESP 300 E spectrometer provided with a T102
rectangular cavity that works with an X band (9.5 GHz). The signal-to-noise
ratio of spectra was increased by accumulation of scans using the
F/Flock accessory to guarantee large field reproducibility. Precautions
to avoid undesirable spectral distortion and line broadenings, such
as those arising from microwave power saturation and magnetic field
overmodulation, were also taken into account to improve sensitivity.
About PubCompare
Our mission is to provide scientists with the largest repository of trustworthy protocols and intelligent analytical tools, thereby offering them extensive information to design robust protocols aimed at minimizing the risk of failures.
We believe that the most crucial aspect is to grant scientists access to a wide range of reliable sources and new useful tools that surpass human capabilities.
However, we trust in allowing scientists to determine how to construct their own protocols based on this information, as they are the experts in their field.
Ready to get started?
Sign up for free.
Registration takes 20 seconds.
Available from any computer
No download required
Revolutionizing how scientists
search and build protocols!