Abstract: The self-developed Raman spectrum test platform was utilized to detect anti-phospholipase A2 receptor (PLA2R) antibody aqueous solutions with varying titers, employing a self-made nano silver colloidal solution as the enhancement medium. It was observed that, under the enhanced effect of the nano silver colloidal solution, PLA2R antibody aqueous solutions with different titers exhibited a characteristic peak at a Raman frequency shift of approximately 1521 cm-1, and the detection limit could reach 2 RU/mL. Based on this finding, further analysis and detection were conducted on urine samples from healthy individuals and mixed PLA2R antibody aqueous solutions. Notably, only in the samples containing mixed PLA2R antibody aqueous solutions could the Raman characteristic peak at 1521 cm-1 be detected. This experiment demonstrated that surface-enhanced Raman spectroscopy (SERS) can effectively detect very low titer PLA2R antibody aqueous solutions. Moreover, SERS-based urine detection holds promising potential as a novel method for clinically non-invasive diagnosis of idiopathic membranous nephropathy and serves as an important guiding principle for determining whether suspected patients require detailed kidney tissue biopsy.

Key words: spectroscopy, Raman characteristic peak, surface-enhanced Raman spectroscopy; anti-phospholipase A2 receptor (anti-PLA2R) antibody, diagnosis