A digital ELISA for multiplexed detection of allergen‐specific IgE against Der p 1, Der p 2, and Der p 23

Abstract

The house dust mite Dermatophagoides pteronyssinus produces major allergens (Der p 1, Der p 2, and Der p 23) that require precise IgE detection for clinical diagnosis. We developed a multiplex digital ELISA using fluorescence‐encoded micromagnetic beads (532 nm/638 nm dual‐wavelength system) coupled with microfluidics to simultaneously quantify serum IgE against these components, with comprehensive evaluation against the clinical standard UniCAP system. The 532 nm channel measured allergen‐specific signals via average brightness increase (ABMB) of enzymatically amplified fluorescence, while 638 nm enabled spectral bead differentiation. Comparative evaluation with UniCAP showed the improved digital ELISA achieved uniform 75.0% sensitivity but variable specificity (42.9%–54.5%) across allergens at the 15.8% ABMB threshold. Sample classification results (Der p 1: 9 positive/6 negative; Der p 2: 7/8; Der p 23: 7/8) demonstrated suboptimal positive predictive values (33.3%–60.0%) versus more favorable negative predictive values (60.0%–85.7%), with likelihood ratios (LR+: 1.31–1.65) and Cohen's κ (0.12–0.25) suggesting limited diagnostic reliability. The automated platform offered 60% reduced sample volume (20 μL vs. 50 μL), multiplex capability, and maintained sensitivity for low‐titer samples, representing an efficient screening solution pending specificity enhancement.