Analysis of protein glycation in human fingernail clippings with near-infrared (NIR) spectroscopy as an alternative technique for the diagnosis of diabetes mellitus

作者：Monteyne Tinne; Coopman Renaat; Kishabongo Antoine S; Himpe Jonas; Lapauw Bruno; Shadid Samyah; Van Aken Elisabeth H; Berenson Darja; Speeckaert Marijn M; De Beer Thomas; Delanghe Joris R^*

来源：Clinical Chemistry and Laboratory Medicine, 2018, 56(9): 1551-1558.

DOI：10.1515/cclm-2018-0239

• glycation
• infrared spectroscopy
• keratin
• nails
• partial least square discriminant analysis

Background: Glycated keratin allows the monitoring of average tissue glucose exposure over previous weeks. In the present study, we wanted to explore if near-infrared (NIR) spectroscopy could be used as a non-invasive diagnostic tool for assessing glycation in diabetes mellitus.
Methods: A total of 52 patients with diabetes mellitus and 107 healthy subjects were enrolled in this study. A limited number (n = 21) of nails of healthy subjects were glycated in vitro with 0.278 mol/L, 0.556 mol/L and 0.833 mol/L glucose solution to study the effect of glucose on the nail spectrum. Consequently, the nail clippings of the patients were analyzed using a Thermo Fisher Antaris II Near-IR Analyzer Spectrometer and near infrared (NIR) chemical imaging. Spectral classification (patients with diabetes mellitus vs. healthy subjects) was performed using partial least square discriminant analysis (PLS-DA).
Results: In vitro glycation resulted in peak sharpening between 4300 and 4400 cm(-1) and spectral variations at 5270 cm(-1) and between 6600 and 7500 cm(-1). Similar regions encountered spectral deviations during analysis of the patients' nails. Optimization of the spectral collection parameters was necessary in order to distinguish a large dataset. Spectra had to be collected at 16 cm(-1), 128 scans, region 4000-7500 cm(-1). Using standard normal variate, Savitsky-Golay smoothing (7 points) and first derivative preprocessing allowed for the prediction of the test set with 100% correct assignments utilizing a PLS-DA model.
Conclusions: Analysis of protein glycation in human fingernail clippings with NIR spectroscopy could be an alternative affordable technique for the diagnosis of diabetes mellitus.

• 出版日期2018-9