Immunoglobulin E (IgE) is a key antibody isotype central to allergic hypersensitivity and antiparasitic immunity. Structurally, IgE is a monomeric Y-shaped glycoprotein composed of two ε-heavy chains and two light chains (κ or λ), stabilized by disulfide bonds. The ε-heavy chain contains four constant domains (Cε1–Cε4), with the Fc region (Cε3–Cε4) enabling high-affinity binding to FcεRI receptors on mast cells, basophils, and dendritic cells. Post-translational glycosylation at conserved asparagine residues enhances its stability and fine-tunes receptor interactions. IgE circulates at low levels in serum but exhibits prolonged tissue residency when bound to FcεRI, priming immune cells for rapid activation. Advantages of this OneStep ELISA Kit Design: Simplified Workflow: Combines sample incubation and detection in a single step, eliminating intermediate washing and reducing hands-on time. High Efficiency: Achieves results within 60 minutes, ideal for high-throughput studies or urgent diagnostics. Enhanced Precision: Minimizes procedural variability and cross-contamination risks through optimized reagent formulation. Broad Compatibility: Validated for diverse biological matrices, ensuring flexibility in experimental design. This kit’s streamlined protocol and robust performance make it an indispensable tool for researchers and clinicians seeking reliable IgE quantification in time-sensitive or resource-limited settings.