Smartphone Dual‐Channel Biosensor for Simultaneous PLGF/sFlt‐1 Detection and Signaling Pathway Analysis

Abstract Preeclampsia in pregnancies affects angiogenesis while the fetus develops. Early diagnosis of preeclampsia can enable timely prognosis and intervention. This study developed a smartphone‐based, label‐free dual‐channel electrochemical biosensing platform for the simultaneous detection of preeclampsia biomarkers, placental growth factor (PLGF) and soluble Fms‐like tyrosine kinase‐1 (sFlt‐1). Based on the functional modification of gold nanoparticles and reduced graphene oxide on working electrodes, the specific surface area is enlarged, and the stability is improved. PLGF and sFlt‐1 antibody serving as sensitive elements, are immobilized on the electrode surface. As PLGF binds sFlt‐1 dynamically, fluidic chambers are designed based on 3D printing for comprehensive detection. The biosensor achieved linear ranges of 10–8000 pg mL ⁻¹ for sFlt‐1 and 1–250 pg mL ⁻¹ for PLGF, meeting clinical diagnostic requirements. Molecular docking is used to analyze the binding properties and signaling pathways of PLGF and sFlt‐1, providing critical diagnostic insights for clinicians. This biosensing platform, featuring a portable integrated circuit and smartphone‐based APP, enables point‐of‐care testing (POCT). Comparison tests using plasma samples from 10 individuals demonstrated a strong correlation (r > 0.98, p > 0.1) with ELISA, indicating the potential in clinical POCT applications for preeclampsia. These results suggest that the sensor can be used as a dual‐channel biomarker for preeclampsia without sample labeling.