Related Experiment Video
Updated: Jul 19, 2025

Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
Extracting accurate infrared lineshapes from weak vibrational probes at low concentrations
Raiza N A Maia1, Sunayana Mitra1, Carlos R Baiz1
1Department of Chemistry, University of Texas at Austin, Austin, TX 78712-1224, USA.
This study presents a new Fourier-transform infrared (FTIR) spectroscopy method to precisely extract weak vibrational probe signals, like thiocyanates, from strong solvent backgrounds for better biological molecule analysis.
Area of Science:
- Biophysical Chemistry
- Spectroscopy
- Molecular Biology
Background:
- Fourier-transform infrared (FTIR) spectroscopy is valuable for analyzing biological molecule structure.
- Weak infrared probes, such as thiocyanates, present challenges due to low signal and solvent interference.
- Accurate detection of weak vibrational modes is crucial for detailed molecular analysis.
Purpose of the Study:
- To develop a streamlined protocol for extracting weak infrared absorption lineshapes.
- To overcome the limitations of low signal strength and solvent overlap in FTIR spectroscopy.
- To enable precise measurements of weak vibrational probes in complex environments.
Main Methods:
- A protocol combining spectral filtering, background modeling, and subtraction was developed.
- The method focuses on precise extraction of weak infrared absorption lineshapes.
- Demonstrated application on methyl thiocyanate CN stretching mode in water.
Main Results:
- Successfully extracted the CN stretching mode peak of methyl thiocyanate at low concentrations (0.25 mM) in water.
- The methodology effectively isolates weak signals from a strong solvent background.
- Achieved unprecedented precision for weak probe detection using FTIR spectroscopy.
Conclusions:
- The developed approach enhances FTIR accuracy for weak vibrational probes.
- This method provides valuable tools for studying protein structure and dynamics.
- Enables new possibilities for detailed molecular investigations in solution.
More Related Videos
12:58Characterizing Individual Protein Aggregates by Infrared Nanospectroscopy and Atomic Force Microscopy
Published on: September 12, 2019
10:03Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Related Concept Videos
IR Spectroscopy: Molecular Vibration Overview
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
According to Hooke's law, the vibrational frequency is directly proportional to...
Infrared (IR) Spectroscopy: Overview
Different compounds display unique properties due to their...
IR Frequency Region: Fingerprint Region
IR Spectrum Peak Intensity: Amount of IR-Active Bonds
IR Frequency Region: X–H Stretching