Demystifying FTIR Spectroscopy Instruments: A Beginner’s Journey

Spectroscopy, a fascinating tool used in scientific research and industries, uncovers the secrets of matter by studying how it interacts with light. One such technique is Fourier Transform Infrared (FTIR) spectroscopy, which allows you to delve into the composition of a wide range of materials.


Imagine having the power to identify chemicals and understand molecular structures simply by shining light on them. You gain a deep understanding of the composition and structure of the materials you encounter. With Agilent FTIR spectroscopy instruments, you can uncover the mysteries of molecular vibrations and chemical bonds. 

Components of an FTIR Spectrometer

An FTIR spectrometer consists of several key components that work together to perform spectroscopic analysis. Learn about them below:

1. Infrared Light Source

This component emits infrared radiation, which is the type of light used in FTIR spectroscopy. The source can be a heated filament, a globar (silicon carbide rod), or a laser, depending on the instrument, providing the necessary energy for sample analysis.

2. Interferometer

The interferometer is a crucial part of the FTIR spectrometer. It splits the infrared light into two beams and recombines them. Which then creates an interference pattern called an interferogram. This contains valuable information about the sample’s interaction with the infrared light.

3. Sample Compartment

Sample compartment is like a designated space in the instrument where the sample to be analyzed is placed. Its purpose is to securely hold the sample. Then, position it in the path of the infrared light. This setup ensures that measurements are done accurately and under controlled conditions.

4. Detector

This captures the recombined infrared light after it has interacted with the sample. Converting the light into an electrical signal, which is then processed for data acquisition. This signal carries information about the intensity of the transmitted or absorbed infrared light, enabling the generation of a spectrum for analysis.

Data Acquisition and Analysis

When it comes to FTIR spectroscopy, acquiring and analyzing data involves a series of important steps. Explore some of these key processes:

1. Collecting an Interferogram

This step involves measuring the intensity of infrared light as it interacts with the sample. To do this, the instrument records the variations in intensity while moving a mirror in the interferometer. These intensity measurements form an interferogram, representing the sample’s interaction with different infrared light frequencies.

It captures valuable information that is later transformed into a spectrum, enabling the identification and analysis of the sample’s chemical properties.

2. Fourier Transform and Spectrum Generation

The interferogram is mathematically transformed using a technique called Fourier Transform. This transformation converts the interferogram from a time-domain representation to a frequency-domain representation, generating a spectrum. The spectrum represents the absorption or transmission of different frequencies of infrared light by the sample.

3. Interpretation of Spectral Data

Generated spectrum is then analyzed to extract useful information. Spectral interpretation involves identifying characteristic peaks or patterns in the spectrum, which can provide insights into the functional groups and chemical bonds present in the sample.

Practical Aspects of FTIR Spectroscopy

This section focuses on the practical considerations involved in conducting FTIR spectroscopy experiments.

Sample Preparation and Handling

Proper sample preparation techniques are important to obtain reliable and accurate results in FTIR spectroscopy. This includes ensuring the sample is clean, homogeneous, and appropriately prepared for analysis. Different sample types may require specific handling considerations to ensure optimal results.

Spectral Interpretation and Analysis

Spectral interpretation involves analyzing the obtained spectrum to understand the chemical information it contains. This can involve identifying characteristic peaks associated with specific functional groups or chemical bonds.

Quantitative analysis may also be performed by measuring the intensity of peaks. Then, correlating them with the concentration of components in the sample. Peak integration, which involves measuring the area under specific peaks, is commonly used for quantitative analysis.

Future Trends and Developments

As technology continues to advance, there are exciting developments in FTIR spectroscopy. These advancements aim to make the instruments smaller and more portable. Bringing the benefits of FTIR spectroscopy to a wider range of applications and environments.

Miniaturization and Portability of Instruments

Currently, FTIR spectrometers are large and stationary machines found in laboratories. However, researchers are working on making them smaller and more portable. This means that FTIR devices could become compact and lightweight, making it easier to use them in various settings.

For example, scientists could take them out into the field for on-the-spot analysis in industries such as pharmaceuticals, environmental monitoring, and forensics. This portability saves time and resources compared to sending samples to a centralized laboratory.

Integration With Other Analytical Techniques

FTIR spectroscopy is already a powerful tool, but its capabilities can be further enhanced by combining it with other techniques. By integrating FTIR spectroscopy with complementary methods, researchers can gain more comprehensive insights into samples.

This integration allows for a deeper understanding of materials’ chemical composition, structure, and properties, benefiting fields like materials science, healthcare, and environmental monitoring.

Explore FTIR Spectroscopy for Limitless Discoveries

Think about the possibilities if you could unlock the secrets hidden within different materials. By delving into FTIR spectroscopy, you can learn how to operate state-of-the-art instruments, prepare samples, and analyze the data. Whether you are interested in pharmaceuticals, environmental monitoring, forensic analysis, or food safety, FTIR spectroscopy has a place for you.