Long-term monitoring of blood biomarkers related to intrauterine growth restriction using AgNPs SERS tags-based lateral flow assay

Sensitive and accurate early detection of fetal growth restriction (FGR) is of vital importance in the development of the fetus during pregnancy and even the health of future life. Here, an ultrasensitive and straightforward surface-enhanced Raman scattering (SERS)-based double targets detection in pregnancy is implemented by utilizing functionalized Ag nanoparticles (AgNPs). Through fabricating 4-MPA antibody-modified AgNPs on the lateral flow assay (LFA) strips as the SERS nanotags, the target proteins in blood samples from pregnancy were accurately captured, which further quantizing PI3K and CRAF in unprocessed blood. This strategy warrant excellent selectivity and sensitivity with the limits of detection (LODs) are 0.76 fg mL-1 for PI3K and 0.61 fg mL-1 for CRAF, leading reliable quantification for these two targets. Meanwhile, the feasibility of this assembly was testified by comparing with conventional ELISA method, and the results showed that a high degree of consistency was obtained in these two detection assays. This SERS-colorimetric dual-signal LFA strip can provide a novel strategy for early diagnosis of fetal-related disorders, which is essential for disease diagnosis and treatment guidance during pregnancy.