Near UV Circular Dichroism Spectroscopy Analysis

Circular dichroism (CD) spectroscopy is a fast, simple, and accurate method for studying protein structures in dilute solutions. The structural analysis was performed using the circular dichroism of proteins and the difference in absorption of left and right circularly polarized light by asymmetric molecules.

The vibrational structure of the protein's near ultraviolet circular dichroism (CD) spectrum (240 to 320 nm) can provide important information about protein conformation. Near-UV CD spectroscopy can reflect the arrangement information of protein side chain chromophore groups tryptophan, phenylalanine, tyrosine and other residues and changes in disulfide bond microenvironment. The separation and relative direction of the chromophore depends on the structure of the protein. Therefore, the near-UV CD spectrum of the protein reflects the conformational difference and can be used to detect the structure and dynamics of protein folding.

All new biotechnology or biological products require spectral analysis as proof of conformity. As a reliable partner of biopharmaceutical companies, Creative Proteomics can provide customers with near UV circular dichroism spectroscopy analysis services based on GLP / GMP.

Near UV Circular Dichroism Spectroscopy Analysis

We Can Provide but Not Limited to:

  • Provide information about the environment and the interaction of aromatic side chains.
  • Monitor and study binding processes.
  • Detect conformational changes caused by sequence modifications.
  • Monitor and study the process of protein folding and unfolding under various conditions.
  • Calculate site-directed mutants to predict the contribution of individual aromatic residues.

The Workflow of Near UV Circular Dichroism Spectroscopy Analysis

Near UV Circular Dichroism Spectroscopy Analysis

The signals in the near UV region will be almost zero if a protein without a defined three-dimensional structure though retains secondary structure. On the other hand, if the protein is folded into a well-defined structure, there would be significant near UV signals. A small change in tertiary structure because of protein-protein interactions or changes in solvent conditions can be detected by the sensitive near UV CD spectrum.

Characteristics of Near UV Circular Dichroism Spectroscopy Analysis

  • Tryptophan residues are characterized near 284 and 297 nm; tyrosine residues are characterized near 277 nm; phenylalanine residues are characterized near 261 and 268 nm. Different from aromatic amino acids, disulfide bonds give rise to broad weak signals throughout the near-UV spectrum.
  • Rapid turnaround time: 5-7 days to provide comprehensive report.
  • Customized service: We can customize exclusive solutions for you based on your samples.

Sample Requirements

  • The purity of samples for CD spectroscopy must be at least 90% (HPLC, MS or SDS-PAGE).
  • Sample concentration> 5 mg / ml.
  • Sample volume> 1 mL.

Creative Proteomics' analytical scientists can provide a clear and concise written report of the spectrum data of the far ultraviolet circular dichroism analysis to help customers analyze the secondary structure of the protein. We can also provide you with a one-stop service from sample preparation, purity analysis to circular dichroism analysis.


  • Li Z, Hirst J D. Quantitative first principles calculations of protein circular dichroism in the near-ultraviolet. Chemical science, 2017, 8(6): 4318-4333.
  • Greenfield N J. Circular dichroism (CD) analyses of protein-protein interactions//Protein-Protein Interactions. Humana Press, New York, NY, 2015: 239-265.

*For Research Use Only. Not for use in the treatment or diagnosis of disease.

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