Table of Contents
FTIR Protein Secondary Structure Analysis Using OriginPro
Protein secondary structure analysis using Fourier Transform Infrared (FTIR) spectroscopy has become one of the most widely used analytical techniques in food science, protein chemistry, biotechnology and pharmaceutical research. Despite its widespread use, many researchers struggle with one important step—converting an FTIR spectrum into meaningful percentages of β-sheet, α-helix, random coil and β-turn structures.
This tutorial provides a complete workflow starting from sample analysis on a PerkinElmer FTIR instrument through to Gaussian peak deconvolution in OriginPro and final secondary structure calculations.
Watch the Complete Tutorial
(FTIR Protein Secondary Structure Analysis in OriginPro | Complete Amide I Deconvolution Tutorial)
What You Will Learn
In this tutorial you will learn:
- FTIR fundamentals
- Protein secondary structure
- ATR-FTIR sample loading
- Amide I region
- Why baseline correction is required
- Why the Amide I region is analysed
- Gaussian peak fitting
- Choosing peak centres
- Fixing peak centres
- Setting peak width bounds
- Area calculations
- Calculating secondary structure percentages
- Exporting publication-quality figures
- Preparing results for research papers
Software Used
- PerkinElmer Spectrum IR
- OriginPro
- Microsoft Excel
Equipment Used
- PerkinElmer Spectrum Two FTIR
- Universal ATR crystal
Why Analyse the Amide I Region?
The Amide I band (1600–1700 cm⁻¹) originates mainly from the C=O stretching vibration of peptide bonds.
Because this vibration is highly sensitive to hydrogen bonding and molecular conformation, the Amide I region provides valuable information about protein secondary structure.
Peak Assignments Used
| Peak | Assignment |
|---|---|
| 1620 | β-sheet |
| 1632 | β-sheet |
| 1642 | Random coil |
| 1654 | α-helix |
| 1670 | β-turn |
| 1688 | High-frequency β-sheet |
Secondary Structure Calculation
The tutorial demonstrates calculation of:
β-sheet (%) = ((P1 + P2 + P6) / Total Area) × 100
Random coil (%) = (P3 / Total Area) × 100
α-helix (%) = (P4 / Total Area) × 100
β-turn (%) = (P5 / Total Area) × 100
Free Excel Calculator
The Excel workbook used in this tutorial is freely available.
Download it here:
(Free Excel Calculator For Secondary Structure Calculation)
Who Is This Tutorial For?
This tutorial is useful for:
- Undergraduate students
- MSc students
- PhD researchers
- Food scientists
- Protein chemists
- Biotechnologists
- Pharmaceutical researchers
- Analytical chemists
Related Topics
- FTIR Spectroscopy
- ATR-FTIR
- Protein Structure
- Gaussian Curve Fitting
- OriginPro Tutorials
- Spectral Deconvolution
- Food Protein Analysis
About Vishal Food Tech
Vishal Food Tech provides tutorials focused on food science research, analytical techniques, spectroscopy, scientific software and publication-ready data analysis.
New tutorials are published regularly.