Noninvasive diagnosis of type 2 diabetes mellitus by hair analysis using laser-induced breakdown spectroscopy (LIBS)

Currently, the reference method for diagnosing the pathology of diabetes is the measurement of glycated hemoglobin HbA1c. As a major public health problem, as categorized by the World Health Organization, the need to develop new techniques that are more accessible, especially for developing countries, is necessary. The objective of this work is to propose a new technique based on laser-induced breakdown spectroscopy (LIBS) using the essential minerals calcium, sodium, magnesium, and zinc in hair as biomarkers for the screening of type 2 diabetes. The study involved 130 women: 24 were classified as low-level diabetics with a glycated hemoglobin HbA1c 7% after clinical tests were performed at the Habib Thameur Hospital in Tunis. The other 50 women were healthy and used as controls. The correlation of the mineral concentrations in the hair with the values of glycated hemoglobin allow an economical and rapid detection of the disease. The results showed a strong negative correlation between the levels of calcium, magnesium, and zinc with the HbA1c values and a strong positive correlation between the intensity of the sodium lines and HbA1c. These results allowed the discrimination of the three groups in the cohort, offering a new approach to quickly classify the patients involved in a screening campaign. In addition, the strong correlation between laser-induced breakdown spectroscopy (LIBS) and the front face fluorescence spectroscopy (FFFS), previously applied on the same samples, may help identify the source of the fluorescence spectra. All of these results support the use of LIBS upon hair to evaluate minerals as effective biomarkers for the detection of type II diabetes to be a promising approach.