Interpretable Multiwavelength SERS Fingerprints of Human Urine for Ischemic Stroke Diagnosis.

Journal: ACS sensors
Published Date:

Abstract

Surface-enhanced Raman spectroscopy (SERS) can capture single-molecule-level component information from complex biological samples by providing their fingerprint profiles. However, increasing complexity and subtle variations in biological media can diminish the discrimination accuracy of traditional SERS excited by a single laser wavelength. Here, we demonstrate a multiwavelength SERS strategy for urine detection, aiming to achieve accurate diagnosis of ischemic stroke (IS). This strategy can acquire more comprehensive and unique chemical information on complex samples by capturing SERS fingerprints under multiple excitation wavelengths and vertically stacking them. Then, a convolutional neural network (CNN) classifier specifically designed for spectral data achieved an accuracy rate of 85.0% and an area under the curve (AUC) of 92.8% in recognizing IS. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to the diagnosis of IS. By correlating the important feature ranges selected by machine learning (ML) with the feature ranges of known biomolecules (such as lysine, arginine, glutamic acid, and hypoxanthine), we verified that the ML model effectively identified the Raman features of IS-related molecules and used a weighted combination of these features for the diagnosis of IS. Meanwhile, based on the multiwavelength SERS spectra stacking strategy, more effective information was extracted for the diagnosis of IS.

Authors

  • Wenrou Yu
    College of Physics, Chongqing University, Chongqing, China.
  • Yao Liu
    Innovation Research Institute of Combined Acupuncture and Medicine, Shaanxi University of CM, Xianyang 712046, China.
  • Yan Du
    State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China; School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China. Electronic address: [email protected].
  • Liu Yang
    Department of Ultrasound, Hunan Children's Hospital, Changsha, China.
  • Hui Wang
    Department of Vascular Surgery, Xuanwu Hospital, Capital Medical University, Beijing, China.
  • Yingzhou Huang
    Chongqing Key Laboratory of Interface Physics in Energy Conversion, College of Physics, Chongqing University, Chongqing 401331, China.

Keywords

No keywords available for this article.