Facile SERS-active chip (PS@Ag/SiO2/Ag) for the determination of HCC biomarker

Hepatocellular carcinoma (HCC), which is one of the deadliest diseases worldwide, has drawn significant attention in recent research. Early diagnosis is important for the quick control and prevention of the disease. Until now, among the various detection methods, the strategies based on surface-enhanced Raman scattering (SERS) are considered the most attractive owing to the high selectivity and sensitivity. In this investigation, we designed a novel type of SERS-active chip for detecting the HCC biomarker Lens culinaris agglutinin-reactive Alpha-fetoprotein, AFP-L3, which utilizes a two-dimensional non-close-packed polystyrene colloid sphere arrays@Ag/SiO2/Ag shell (PS@Ag/SiO2/Ag) composite structure with different sizes as the SERS-active chip and an antibody-conjugated Ag/SiO2/Ag surface labeled with 5,5-Dithiobis (succinimidyl-2-nitrobenzoate) (DSNB) as the SERS probe. A good linear relationship between the concentration of AFP-L3 and the Raman intensity ratio I1390/I1074 of DSNB was obtained, with the correlation coefficient R2 = 0.997. Moreover, when the proposed SERS-active chip was utilized over the range of AFP-L3 concentrations 0-8 ng/mL, the limit of detection (3σ) was determined to be 0.078 ng/mL. The developed method was applied to the determination of AFP-L3 in three serum samples collected from patients diagnosed with liver disease, demonstrating its potential for application in clinical diagnosis.