Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) Spectroscopy Analysis of Saliva for Breast Cancer Diagnosis

Abstract

Saliva biomarkers using reagent-free biophotonic technology have not been investigated as a strategy for early detection of breast cancer (BC). The attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy has been proposed as a promising tool for disease diagnosis. However, its utilization in cancer is still incipient, and currently saliva has not been used for BC screening. We have applied ATR-FTIR onto saliva from patients with breast cancer, benign breast disease, and healthy matched controls to investigate its potential use in BC diagnosis. Several salivary vibrational modes have been identified in original and second-derivative spectra. The absorbance levels at wavenumber 1041 cm−1 were significantly higher (p<0.05) in saliva of breast cancer patients compared with those of benign patients, and the ROC curve analysis of this peak showed a reasonable accuracy to discriminate breast cancer from benign and control patients. The 1433–1302.9 cm−1 band area was significantly higher (p<0.05) in saliva of breast cancer patients than in control and benign patients. This salivary ATR-FTIR spectral area was prevalidated as a potential diagnostic biomarker of BC. This spectral biomarker was able to discriminate human BC from controls with sensitivity and specificity of 90% and 80%, respectively. Besides, it was able to differentiate BC from benign disease with sensitivity and specificity of 90% and 70%, respectively. Briefly, for the first time, saliva analysis by ATR-FTIR spectroscopy has demonstrated the potential use of salivary spectral biomarkers (1041 cm−1 and 1433–1302.9 cm−1) as a novel alternative for noninvasive BC diagnosis, which could be used for screening purposes.

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

“…The air spectra was used as a background in ATR-FTIR analysis. Sample spectra and background was taken with 4 cm -1 of resolution and 32 scans were performed for salivary analysis [52,53].…”

Investigations into the Effects of pH on Quantitative Measurements of Lactate in Biological Media Using ATR-FTIR Spectroscopy

“…When used in combination with Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy, these technique could provide rapid, robust and stable sample analysis. ATR-FTIR spectroscopy has already been used to detect biochemical constituents of whole blood [12][13][14], as well as other biological fluid components with high accuracy and sensitivity (which is application specific, more than 90% [15] and >70% [16]), suited to clinical decision making even on un-treated samples. However, the major fundamental limitation of this technique is selectivity towards the analyte of concern in a pool of similar chemical constituents, especially as found in whole blood [17].…”

Monitoring of Peripheral Blood Leukocytes and Plasma Samples: A Pilot Study to Examine Treatment Response to Leflunomide in Rheumatoid Arthritis

“…The ATR unit was cleaned and dried every time, previous to the next infrared analysis. The plasma samples were dried using airflow on ATR-crystal for 3 min before obtaining the sample spectra over the range of 4000 to 400 cm −1 in a room with a controlled temperature 21–23 °C [ 38 , 39 ].…”

“…The second derivative generates valleys from the original absorption spectrum. Therefore, the analyzed wavenumbers in the second derivative are the height of valleys [ 38 , 40 ].…”