Fourier Transform Infrared–Attenuated Total Reflectance Spectroscopy (FTIR-ATR) spectra were recorded in the 4000 to 400 cm−1 range using a Jasco FT/IR 6200 spectrometer (JASCO Inter. Co., Ltd., Tokyo, Japan) equipped with an MCT M detector cooled by liquid nitrogen (77 K) and a MIRacle ATR sampling accessory (diamond/ZnSe) (PIKE Technol., Madison, WI, USA). The whole spectrometric system was purged by dry argon. The scanning rate was 0.1 cm/s. Signal accumulation from 300 scans was taken with a resolution of 1 cm−1. Interesting parts of the spectra were analyzed according to a numerical peak-fitting algorithm (PeakFit™, Systat Software Inc., San Jose, CA, USA).
Peakfit
Manufactured by Grafiti LLC
Sourced in United States
PeakFit is a laboratory instrument designed for precise peak analysis and deconvolution. It provides advanced analytical capabilities to researchers and scientists for the identification and quantification of complex sample components.
Automatically generated - may contain errors
Lab products found in correlation
Tensor 27 ft ir spectrophotometer, by Bruker (1 mentions)
Sequi gen gt system, by Bio-Rad (1 mentions)
Imagequant software, by GE Healthcare (1 mentions)
Amersham typhoon biomolecular imager, by GE Healthcare (1 mentions)
Image gauge, by Fujifilm (1 mentions)
Atr ftir spectrometer, by Thermo Fisher Scientific (1 mentions)
9 protocols using peakfit
1
FTIR-ATR Spectroscopy Protocol for Materials
2
ATR-FTIR Analysis of Protein to Fibril Transition
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The structural transition from proteins/peptides to fibrils was studied by attenuated total reflection FTIR (ATR-FTIR). The ATR-FTIR spectra were recorded on a Tensor 27 FTIR spectrophotometer (Bruker) in conjunction with OPUS data collection software. We used high concentrations (~12 mg/ml) of fresh protein samples for FTIR analysis. The freshly prepared fibrils were washed three times with D2O water to remove any residual proteins and were then re-suspended in a small amount of D2O. The samples were evenly spread on an internal reflection element (IRE) crystal using a micropipette tip. The buffer and D2O spectra were used as background for protein and fibril samples, respectively. The data were collected as an average of 128 scans at 1 cm−1 resolution. PeakFit (Systat Software Inc.) was used for spectral processing and data analysis. We plotted the amide I band at 1600–1700 cm−1 to record specific spectral features in amyloids.
3
HPLC Quantification of Acenocoumarol
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Acenocoumarol concentration was determined by using reverse-phase high-performance liquid chromatography (RP-HPLC) by modification of a previously reported method (De Orsi et al. 1998) . Hewlett Packard HP 1100 HPLC equipment with UV detection was used. Diode array detector was set at 280 nm. Chromatographic separations and subsequent quantifications were carried out at room temperature using a LiChrospher 100 RP-18 (4×250 mm, 5 μm) column. The mobile phase consisted of acetonitrile (Biopack, Z árate, Buenos Aires, Argentina)/phosphoric acid (Cicarelli, San Lorenzo, Santa Fe, Argentina) 60/40, prepared with MilliQ water, and the flow rate was adjusted to 1.2 mL/min at 25 • C. Mobile phase was filtered before use (Nylon membranes, 0.45 μm,13 mm, Osmonics Inc, Fisher Scientific, Pittsburgh, PA) and samples were previously filtered through 0.22 μm filters (GVS ABLUO, Sanford, FL). The injection volume was 20 μL and each sample was analyzed in triplicate. Peak areas were used for quantitative analyses. Calibration curve of peak areas versus acenocoumarol concentration was made with different dilutions of a stock solution (1.6 mg/mL). Linear relationship was observed in the range of 0.001-0.050 mg/mL. Retention times (t R ) and peak areas were evaluated using PeakFit (Systat Software, Inc, San Jose, CA).
4
Temporal Stability of nsp12-nsp8 Complex
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The temporal stability of the nsp12-nsp8 complex was assessed with a large scale 300 μL assembly reaction of 20 μM nsp12 with 60 μM nsp8 and using gel filtration chromatography in 100 mM NaCl, pH 7, 10% glycerol to purify the complex as a 0.5-mL sample from the leading edge of the peak at ≈12-mL retention volume. This purified complex was incubated at room temperature, and 50-μL aliquots were periodically reinjected onto the column over an 18-h time course (Fig. 3E ). The areas of the overlapping nsp12-8 and nsp12 peaks in the resulting chromatograms were determined by mathematical peak fitting (PeakFit, Systat Software) and corrected for their different extinction coefficients (http://web.expasy.org/protparam ) to calculate the relative concentrations present in the loaded sample aliquots.
5
Electrochemical Redox Analysis of α3NH2Y
6
Laurdan Membrane Polarity Evaluation
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Laurdan is sensitive to the polarity around the molecule itself,
and its fluorescence properties enable us to evaluate the surface
polarity of lipid membranes. The Laurdan emission spectra exhibit
a redshift caused by dielectric relaxation. These spectra were measured
with an excitation wavelength of 340 nm, and the general polarization
(GP340), the membrane polarity, was calculated
as follows where I440 and I490 represent the fluorescence intensities of
Laurdan at 440 and 490 nm, respectively. The total concentrations
of lipid and Laurdan were 100 and 1 μM, respectively. The fluorescence
spectrum of Laurdan was deconvoluted into two spectra using
the software Peakfit (Systat Software Inc., San Jose, CA): one originates
from the localization of Laurdan in an ordered membrane (ordered phase)
and the other originates from the localization of Laurdan in a disordered
membrane (disordered phase). By calculating the area below the spectrum
originating from the ordered phase (Ao) and the area below the spectrum originating from the disordered
phase (Ad), the area ratio of ordered
phase to disordered phase in the actual vesicle sample (Ao/Ad) was determined.
and its fluorescence properties enable us to evaluate the surface
polarity of lipid membranes. The Laurdan emission spectra exhibit
a redshift caused by dielectric relaxation. These spectra were measured
with an excitation wavelength of 340 nm, and the general polarization
(GP340), the membrane polarity, was calculated
as follows where I440 and I490 represent the fluorescence intensities of
Laurdan at 440 and 490 nm, respectively. The total concentrations
of lipid and Laurdan were 100 and 1 μM, respectively. The fluorescence
spectrum of Laurdan was deconvoluted into two spectra using
the software Peakfit (Systat Software Inc., San Jose, CA): one originates
from the localization of Laurdan in an ordered membrane (ordered phase)
and the other originates from the localization of Laurdan in a disordered
membrane (disordered phase). By calculating the area below the spectrum
originating from the ordered phase (Ao) and the area below the spectrum originating from the disordered
phase (Ad), the area ratio of ordered
phase to disordered phase in the actual vesicle sample (Ao/Ad) was determined.
7
WAXD Analysis of Drawn and Undrawn Polymer Fibers
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
For WAXD analyses, fiber bundles of approx. 50–60 tex (mg m−1) were mounted on a custom-made sample holder. For the drawn COP and CoPA fibers, the fiber bundles consisted of 8 and 16 single filaments, respectively. To analyze the undrawn (free fall) COP fiber, two single filaments (31.8 tex each) were combined. WAXD patterns were recorded on an Xcalibur PX four-circle single-crystal diffractometer (Oxford Diffraction, Yarnton, Oxfordshire, UK; κ geometry; Mo Kα1 radiation, λ = 0.709 26 Å, CCD area detection system) and evaluated by means of the CrysAlis Pro Data collection and processing software [18 (link)] and the XRD2DScan displaying and analyzing software [19 ]. For peak fitting purposes, the peak separation and analysis software package PeakFit (Version 4.12, Systat Software GmbH, Erkrath, Germany) was used. Peak fitting was performed using the Pearson type VII distribution function.
8
Quantitative RNA Elongation Analysis
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
Quenched reactions were mixed 1:1 with FBD loading dye and heated for 10 min at 70 °C, and cooled on ice for 2 min before analysis on 17–20% polyacrylamide, 7 M Urea TBE gels. Gels were run at a constant 65 W using Sequi-Gen GT Systems from Bio-Rad or vertical electrophoresis systems from CBS Scientific and visualised using an Amersham™ Typhoon™ Biomolecular Imager (GE Healthcare). The intensity of each band was quantified using the ImageQuant software (GE Healthcare)/Image Gauge (Fuji) and/or using ImageJ as implemented in the Fiji package, with background subtraction. Product yield was determined by dividing the intensity of the product by total intensity of the product + remaining primer and multiplying by the input concentration of RNA. For the rapid quench data, the programme PeakFit (Systat Software) was used to fit gel lane profiles to a set of gaussian peaks and the fractional area contained within each peak was multiplied by the RNA concentration in the experiment to calculate the amount of each elongation species as a function of reaction time.
9
Characterization of Protein Secondary Structure
Check if the same lab product or an alternative is used in the 5 most similar protocols
+ Expand
The secondary structure was characterized by an ATR-FTIR spectrometer (Thermo Scientific, Waltham, MA, USA) over a wavenumber range of 700–4000 cm−1. The peak de-convolution of conformations in the amide I region was conducted using PeakFit (Version 4.12, Systat Software, San José, USA).
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!