Breaking the picomolar barrier in lateral flow assays using Bright-Dtech___ 614 -- Europium nanoparticles for enhanced sensitivity

TL;DR

This study introduces Bright-Dtech___-614 Europium nanoparticles to significantly enhance the sensitivity of lateral flow immunoassays, enabling detection of biomarkers at femtomolar levels for improved clinical diagnostics.

Contribution

We developed a novel Eu nanoparticle-based LFIA that achieves femtomolar detection limits, surpassing traditional methods and expanding LFIA applications in precision medicine.

Findings

Achieved a detection limit of 38 pg/mL for h-LDH.

Demonstrated 686-fold sensitivity improvement over gold nanoparticle LFIA.

Exhibited high accuracy and reproducibility in serum samples.

Abstract

Lateral flow immunoassays (LFIA) are among the most widely used rapid diagnostic tests for point-of-care screening of disease biomarkers. However, their limited sensitivity hinders their use in complex clinical applications that require accurate biomarker quantification for precise medicine. To address this limitation, we evaluated Bright-Dtech___-614 Europium nanoparticles to enhance LFIA assay sensitivity. These nanoparticles exhibited a luminescence quantum yield of 70 % and a 90 % conjugation efficacy with antibodies by direct adsorption. Considering these properties, we developed an LFIA to quantify human lactate dehydrogenase (h-LDH), a biomarker and therapeutic target in cancer disease. The Bright-Dtech___-614 Eu nanoparticle-based assay achieved a detection limit of 38 pg mL -1 , representing a 686-fold, 15-fold, and 2.9-fold improvement in sensitivity over conventional LFIA platforms using gold (AuNPs), carbon nanoparticles, and standard ELISA, respectively. The assay exhibited strong accuracy, with a mean recovery rate of 108 $\pm$ 11 %, and demonstrated excellent reproducibility, as evidenced by inter-and intra-batch RSD values of 4.9 % and 9.7 %, respectively, when testing LDH-spiked serum samples. By substituting traditional gold nanoparticles with the Bright-Dtech___-614 Eu nanoparticles, we achieved detection limits in the femtomolar range, significantly broadening the applicability of LFIA for precision medicine.