Salivary molecular spectroscopy: a sustainable, rapid and non-invasive monitoring tool for diabetes mellitus during insulin treatment

Douglas C. Caixeta, Emília M. G. Aguiar, Léia Cardoso-Sousa, Líris M. D. Coelho, Stephanie W. Oliveira, Foued S. Espindola, Leandro Raniero, Karla T. B. Crosara, Matthew J. Baker, Walter L. Siqueira, Robinson Sabino-Silva

Research output: Contribution to journalArticlepeer-review

43 Citations (Scopus)
14 Downloads (Pure)


Monitoring of blood glucose is an invasive, painful and costly practice in diabetes. Consequently, the search for a more cost-effective (reagent-free), non-invasive and specific diabetes monitoring method is of great interest. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy has been used in diagnosis of several diseases, however, applications in the monitoring of diabetic treatment are just beginning to emerge. Here, we used ATR-FTIR spectroscopy to evaluate saliva of non-diabetic (ND), diabetic (D) and insulin-treated diabetic (D+I) rats to identify potential salivary biomarkers related to glucose monitoring. The spectrum of saliva of ND, D and D+I rats displayed several unique vibrational modes and from these, two vibrational modes were pre-validated as potential diagnostic biomarkers by ROC curve analysis with significant correlation with glycemia. Compared to the ND and D+I rats, classification of D rats was achieved with a sensitivity of 100%, and an average specificity of 93.33% and 100% using bands 1452 cm-1 and 836 cm-1, respectively. Moreover, 1452 cm-1 and 836 cm-1 spectral bands proved to be robust spectral biomarkers and highly correlated with glycemia (R2 of 0.801 and 0.788, P < 0.01, respectively). Both PCA-LDA and HCA classifications achieved an accuracy of 95.2%. Spectral salivary biomarkers discovered using univariate and multivariate analysis may provide a novel robust alternative for diabetes monitoring using a non-invasive and green technology.

Original languageEnglish
Article numbere0223461
Number of pages18
JournalPLoS ONE
Issue number3
Publication statusPublished - 17 Mar 2020


  • diabetes mellitus
  • saliva
  • insulin
  • glucose
  • biomarkers


Dive into the research topics of 'Salivary molecular spectroscopy: a sustainable, rapid and non-invasive monitoring tool for diabetes mellitus during insulin treatment'. Together they form a unique fingerprint.

Cite this