Comparison of Surface‐Enhanced Raman Spectral Datasets of Filtrate Portions of Blood Serum Samples of Dengue and Typhoid Infected Patients Using 30 kDa Ultra‐Filtration Devices

ABSTRACT Dengue and typhoid are major global health challenges, which are two different but closely related diseases having common symptoms, which may lead to misdiagnosis and cause hindrance in the early screening of these infectious diseases. This demands the development of rapid and accurate screening and diagnostic methods for the comparison of biochemical changes associated with these diseases to identify the differences among them, which can help with early screening and effective management strategies. This study investigates the potential of surface‐enhanced Raman spectroscopy (SERS) as a sensitive technique for the analysis of filtrate portions of blood serum samples of dengue and typhoid patients. For this purpose, serum samples from patients with dengue and typhoid were collected, and filtrate portions were separated using 30 kDa ultra‐filtration devices followed by SERS spectral acquisition. This helps to separate disease‐related biomarkers from high molecular weight proteins, which hinder the detection of low molecular weight biomolecules potentially associated with the development of disease. The SERS spectra were analyzed by employing principal component analysis (PCA) and partial least squares‐discriminant analysis (PLS‐DA). PCA is found helpful to differentiate samples of dengue and typhoid infections based on their unique SERS spectral features. The PLS‐DA as a classification model achieved an AUC value of 0.69 with specificity, sensitivity, and accuracy of 0.92, 0.91, and 0.94, respectively. The differentiating SERS spectral features associated with two different diseases but having common symptoms were identified, which are found helpful for the early screening of these infectious diseases based on their distinct biomarkers.