Talanta. 2026 Apr 1;300:129230. doi: 10.1016/j.talanta.2025.129230. Epub 2025 Dec 13.
ABSTRACT
Immunoassays are indispensable tools in biomedical research and diagnostics, but conventional approaches such as ELISA demand large sample volumes and long assay times, making them unsuitable for precious biological fluids like single-embryo culture medium (ECM). Here we present a novel mechanical buoyant microsphere immunoassay platform that enables reliable analysis of microliter-scale samples. Buoyant hollow glass microspheres (40-60 μm) serve as the reaction carriers, passively aggregating by buoyancy for extraction and sequential transfer across reagent droplets. Through a droplet-based design, in which droplets are stabilized on hydrophilic traps patterned on a hydrophobic surface, each assay requires only 2 μL of sample. By using a custom quantification chip to standardize the microsphere number to 25, the system achieved high reproducibility (coefficients of variation, CV values
PMID:41418617 | DOI:10.1016/j.talanta.2025.129230