An integrated pressure-based lateral flow immunoassay for microliter whole-blood AFP detection at the point of care

Alpha-fetoprotein (AFP) is a widely used biomarker for the diagnosis and postoperative surveillance of hepatocellular carcinoma (HCC). However, current AFP assays rely on centralized laboratories, bulky instrumentation, and labor-intensive sample pretreatment, limiting their applicability in point-of-care and home-based settings. Here, we present an in vitro diagnostic device for quantitative AFP detection in whole blood that integrates a lateral flow immunoassay (LFIA) with a portable pressure meter (PM-LFIA). The platform employs a pressure-based signal readout using nanozyme-catalyzed gas generation to enable sensitive quantification while reducing optical and matrix-related interference. Compared with conventional methods, the PM-LFIA platform achieves a 35-fold reduction in required sample volume and a 215-fold improvement in detection limit. The platform enables AFP detection from 1 μL of unprocessed whole blood within 30 min, supporting point-of-care applications where sample volume is limited. The feasibility of this approach was validated by direct quantification of AFP in 30 whole blood samples, with results consistent with hospital-based measurements. In addition, the applicability of the PM-LFIA platform was demonstrated for other cancer biomarkers, including CEA and CA199. Although environmental sensitivity and device calibration remain challenges, this work demonstrates an integrated and practical strategy for quantitative biomarker detection in whole blood using a portable, low-sample-volume format.