Homogeneous Multiplex Immunoassay for One-Step Pancreatic Cancer Biomarker Evaluation

Pancreatic cancer is one of the foremost malignant gastrointestinal tumors, with prognosis and postoperative prediction remaining challenging because of the lack of facile, sensitive diagnostic methods and a specific single biomarker. Combined-biomarker analysis which provides a promising strategy to conquer such dilemma still requires developments in methodologies to gain accurate and reliable outcomes with wash-/separation-free scenarios and minimal interferences. Herein, a multiplex single-particle homogeneous immunoassay was proposed by simultaneously evaluating three pancreatic cancer-related biomarkers. Owing to the excellent resolution and multielement detectors without mass spectra overlapping, single-particle ICP-MS simultaneously provided biomarkers (CA125, CEA, and CA199) with three to four order-of-magnitude linear ranges and low-level limits of detection from specific antibody-labeled noble metal nanoparticles (AuNPs, AgNPs, and PtNPs). By scrutinizing both intensity and frequency signals, the proposed method was successfully applied in patients' serological evaluation, with results correlating well with those measured by the clinical routine method. The proposed method provides a potential tool in risk assessment of disease recurrence and survival.