Fourier Transform Infrared (FT-IR) Spectroscopy Technology

Fourier transform infrared (FT-IR) spectroscopy is a non-destructive and sensitive method for studying the higher-order structure of proteins/peptides, which is widely used in various fields such as biotechnology, biochemistry, and pharmaceuticals. It provides valuable information about the stability of proteins under different conditions, making it an important tool for protein/peptide research. With decades of rich experience in developing and performing FT-IR analytical methods, CD Formulation uses FT-IR spectroscopy to provide reliable analytical support for the development and characterization of your protein/peptide drugs, from early development to late product release testing.

What is Fourier Transform Infrared (FT-IR) Spectroscopy?

FTIR is a spectral technology based on infrared photon absorption. This photon will stimulate the vibration of the molecular keys, and the characteristic spectrum generated is generated to help identify and represent samples. FTIR analysis can be performed in transmission or reflex mode. Although this method cannot provide accurate atomic resolution molecular structures, it is very sensitive to the changes in the conformity changes when protein changes between functional transformation or between molecular. Its working principle is the light that detects specific frequencies corresponding to internal vibration bonds to the molecule. When the vibration energy matches the medium infrared light, the key will absorb the energy. Because different keys are vibrated with different energy, they will absorb infrared radiation of different wavelengths. The ex -spectrum and its respective absorption bands in terms of position and strength form a unique molecular fingerprint.

Fig. 1 Schematic presentation of the infrared experimental setup. (Bakshi K, et al., 2014)

Fourier Transform Infrared (FT-IR) Spectroscopy Principle

The principle of FTIR spectroscopy is based on the vibration and rotation of atoms in the internal structure of proteins and peptides. When infrared radiation passes through the sample, the protein molecules absorb the radiation energy of a specific wavelength, which is the spectral value. By comparing the measured spectrum with a spectral database, FTIR spectroscopy can be used to identify the protein or peptide of interest.

In FTIR analysis, the fingerprint FTIR spectrum of protein and peptides absorbs the telescopic vibration of the amide I and the amide II.

The amide I band (1690-1600 cm⁻¹) is caused by the C=O stretching vibration of the peptide bond and is modulated by the secondary structure (α-helix, β-sheet, etc.). The secondary structure content can be obtained by comparing the measured spectrum with the spectrum of proteins with known secondary structure.

The amide II band (1600-1500 cm⁻¹) is formed by the CN stretching vibration combined with the NH bending. The amide II absorbance can be used to report the protein unfolding.

Fig. 2 FTIR spectrum of a typical protein illustrating the Amide I and Amide II bands at ~1650 cm⁻¹ and ~1540 cm⁻¹, respectively.(Miller LM, et al., 2013)

Our Services Related to Transform Infrared (FT-IR) Spectroscopy

Thanks to decades of experience in supporting protein/peptide biopharmaceutical development and manufacturing using FT-IR technology, our team of highly qualified experts offers a range of FT-IR-related services to accelerate the implementation and success of your projects.

Our experienced team of experts has completed hundreds of protein and peptide FT-IR analysis projects, allowing support for all stages of your protein/peptide drug development and manufacturing - from early research to downstream process monitoring and GMP batch release testing.

Utilizing cutting-edge FT-IR technology, we support the following protein/peptide characterization programs, including but not limited to:

Protein and Peptide HOS Characterization

Protein and peptide HOS characterization is one of the main applications of FT-IR in protein and peptide drug characterization. Our scientists determine the structural characteristics of proteins and peptides by measuring a series of characteristic infrared absorption bands (fingerprint FTIR spectrum absorption bands of proteins and peptides).

The correspondence between the typical infrared values of amides I, II, and III in protein and peptide structure and the secondary structure is:

Protein and Peptide Aggregation Characterization

Identifying and quantifying the aggregation is an important test program in the development of protein and peptide therapy agents because the agglomeration will affect the effect of drugs and cause immunogenic reactions. Our scientists use FT-IR to accurately identify and quantify different forms of aggregation in the process of drug storage, formulation, and manufacturing to accelerate your drug development process.

Protein and Peptide Conformation & Stability Analysis

Understanding changes in protein structure is essential for evaluating its stability and function. Our scientists obtain the structural information of proteins and peptides under different conditions by analyzing specific peaks in the FT-IR spectrum, such as pH, temperature or chemical modification, etc.

Available Types of FT-IR Spectroscopy Analysis

Water interferes with FTIR measurements of protein samples because it absorbs strongly in the amide I region. When analyzing your protein or peptide sample, our scientists will first consider converting it into a lyophilized (freeze-dried) sample. For samples that can‘t be lyophilized, we will measure them by transmission infrared (IR) spectroscopy and attenuated total reflectance (ATR) enhanced FTIR spectroscopy. However, this requires a relatively high protein concentration (usually >5 mg/mL).

Transmission IR Spectroscopy

The transmission IR spectroscopy is a spectrum detected after transmitting infrared light through the sample, which is suitable for solid, liquid, and gas samples. In this technology, protein samples are placed in a special sample box and then measured by a bouquet of infrared light. This light interacts with chemical bonds in proteins, which produces a unique spectral diagram.

Attenuated Total Reflection (ATR) Enhanced FT-IR Spectroscopy

ATR is a technique that places the sample directly on the ATR crystal for spectral testing, which can effectively reduce the sample preparation process and improve the speed and accuracy of analysis. This method does not require sample processing and is suitable for samples that need to be analyzed quickly.

In addition to the above-mentioned FT-IR spectroscopy analysis, our analytical laboratory is also equipped with a state-of-the-art FTIR microscope, a device that combines the functionality of an optical microscope with the analytical capabilities of FTIR spectroscopy to support the visualization analysis of particles in your protein/peptide biopharmaceutical samples.

Advantages of Our Transform Infrared (FT-IR) Spectroscopy Technology

• High sensitivity for excellent capture of weak signals with high spectral accuracy.
• High resolution and throughput for simultaneous collection of all wavelengths from near-infrared (NIR) to far-infrared (FIR) spectra.
• Label-free, non-destructive technology to accommodate large sample sizes.
• Rapid data acquisition with minimal sample preparation.
• Quantitative analysis.

Custom Transform Infrared (FT-IR) Spectroscopy Services

Why Choose Our Transform Infrared (FT-IR) Spectroscopy Technology?

• We have a team of experts with rich experience in FT-IR analytical method development and validation.
• We have accumulated decades of expertise and successful project experience using FT-IR technology to support protein/peptide biopharmaceutical development.
• Our analytical laboratories are equipped with state-of-the-art FT-IR instruments that can efficiently and accurately analyze the secondary and tertiary structures of protein and peptide molecules.
• We provide customized characterization and expert data interpretation.
• We offer flexible experimental design and customized solutions to meet the needs of your different projects.
• We value our partnership with our customers and are committed to providing continuous support and guidance during the project to ensure that your plan is implemented smoothly.
• Fast turnaround time: comprehensive reports are provided within 1 to 4 weeks depending on sample size and services selected.

Publication

CD Formulation aims to provide a powerful analytical tool for protein and peptide HOS (secondary, tertiary) characterization. Please feel free to contact us if you are interested in our services. Learn how our FT-IR spectroscopy technology can support the smooth implementation of your protein/peptide biopharmaceutical program.

How It Works

STEP 1

Submit a service request describing your specific research or development need.

STEP 2

We'll email you to provide your quote and confirm order details if applicable.

STEP 3

Execute the project with real-time communication, and deliver the final report promptly.