Journal of Biomolecular NMR

, Volume 58, Issue 2, pp 83–99 | Cite as

SARA: a software environment for the analysis of relaxation data acquired with accordion spectroscopy

  • Bradley J. Harden
  • Dominique P. FruehEmail author


We present SARA (Software for Accordion Relaxation Analysis), an interactive and user-friendly MATLAB software environment designed for analyzing relaxation data obtained with accordion spectroscopy. Accordion spectroscopy can be used to measure nuclear magnetic resonance (NMR) relaxation rates in a fraction of the time required by traditional methods, yet data analysis can be intimidating and no unified software packages are available to assist investigators. Hence, the technique has not achieved widespread use within the NMR community. SARA offers users a selection of analysis protocols spanning those presented in the literature thus far, with modifications permitting a more general application to crowded spectra such as those of proteins. We discuss the advantages and limitations of each fitting method and suggest a protocol combining the strengths of each procedure to achieve optimal results. In the end, SARA provides an environment for facile extraction of relaxation rates and should promote routine application of accordion relaxation spectroscopy.


Accordion Relaxation rate Software Analysis SARA 



This work was supported by NIH, Grant R01-GM104257.

Supplementary material

10858_2013_9807_MOESM1_ESM.docx (954 kb)
Supplementary material 1 (DOCX 953 kb)


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of Biophysics and Biophysical ChemistryJohns Hopkins University School of MedicineBaltimoreUSA

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