Real time SERS selective detection sensor for Galectin-1 based on RF-sputter AgNPs islands

Galectin -1 is a dimeric beta-galactoside binding protein secreted mainly through metastatic tumor cells and plays a critical tumorigenic milieu. Galectin-1 is a potent biomarker for diagnosing pancreoductal adenocarcinoma, a type of pancreatic cancer. In this work, the surface-enhanced Raman spectroscopy (SERS) technique was studied for its use in diagnosing PDAC. A silver sputtered array platform was synthesized and coupled by NHS-EDC linker protein via sulfo-NHS-ester. To specify this platform, monoclonal Anti-GAL-1 was attached to analyze the GAL-1 antigen by surface-enhanced Raman spectroscopy (SERS). The final platform, anti-GAL-1/GAL-1/EDC-NHS/Ag, was characterized by FT-IR, AFM, XPS, and Raman spectroscopic techniques. SERS achieved good sensitivity and linearity with this optimized platform. Under optimal conditions, the fabricated platform showed good linearity in the physiological range of 1 ng/ml to 100 ng/ml with LOD 2.45 ng/ml. The modified AgNPs platform has good sensitivity, cost-effectiveness, reliability, and scalability.