Label‐free diagnosis for colorectal cancer through coffee ring‐assisted surface‐enhanced Raman spectroscopy on blood serum

Abstract

Surface-enhanced Raman spectroscopy (SERS) is garnering considerable attention for the swift diagnosis of pathogens and abnormal biological status, that is, cancers. In this work, a simple, fast and inexpensive optical sensing platform is developed by the design of SERS sampling and data analysis. The pretreatment of spectral measurement employed gold nanoparticle colloid mixing with the serum from patients with colorectal cancer (CRC). The droplet of particle-serum mixture formed coffee-ring-like region at the rim, providing strong and stable SERS profiles. The obtained spectra from cancer patients and healthy volunteers were analyzed by unsupervised principal component analysis (PCA) and supervised machine learning model, such as support-vector machine (SVM), respectively. The results demonstrate that the SVM model provides the superior performance in the classification of CRC diagnosis compared with PCA. In addition, the values of carcinoembryonic antigen from the blood samples were compiled with the corresponding SERS spectra for SVM calculation, yielding improved prediction results. K E Y W O R D S colorectal cancer diagnosis, label-free detection, machine learning, nanoparticles, SERS

Filter paper based SERS substrate for the direct detection of analytes in complex matrices

“…drop-casting, which dries into a very non-uniform nanoparticle coffee-ring. 21,26,[33][34][35] The corresponding AFM images of the film on glass (Fig. 2B-D) indeed show that the film is not featureless but rather is composed of fused flatted disks <100 μm in diameter and <1 μm thick, which are the result of partly dried droplets sticking to the surface and then evaporating to dryness.…”

Raman Imaging and Fluorescence Lifetime Imaging Microscopy for Diagnosis of Cancer State and Metabolic Monitoring

“…Stages 1 and 2 differed significantly from stages 3 and 4, enabling a distinction between early and late-stage CRC to be made [ 108 ]. A similar study was performed by Hong et al using SERS on blood samples from CRC patients instead of urine [ 109 ]. Similarly, 1:1 dried mixtures of blood samples with gold nanoparticles were analyzed.…”

“…Healthy donors showed higher signals of amino acids such as phenylalanine and tyrosine compared to CRC patients, whereas in diseased patients, lipid signals were statistically higher compared to controls at several spectral regions (1141, 1263 and 1484 cm −1 ). With machine learning tools such as PCA and support vector machines, the authors were able to classify both groups with accuracies of 90%, yielding a specificity of 100% [ 109 ].…”

A Comprehensive Review on Raman Spectroscopy Applications

“…The diagnosis accuracy of tumors can be significantly improved using Raman spectroscopy [137]. Evidence was found for the diagnosis of enchondroma and chondrosarcomas [138], thyroid cancer [139], lung cancer [140], ovarian cancer [141], breast cancer [142], colorectal cancer [143], prostate cancer [144], and many others [145].The advantage of this technique is that the analyses are carried out directly on biological samples that are often easy to obtain (serum, blood, saliva, urine, sperm, etc. ), and the results are obtained in a short time.…”