Nanoparticle-Based Proximity Ligation Assay for Ultrasensitive, Quantitative Detection of Protein Biomarkers.

ABSTRACT: Proximity ligation assay (PLA) achieves extremely low limits of detection but requires the synthesis of antibody-DNA conjugates recognizing multiple target epitopes with appropriate proximity. In this work, we introduce a more generally applicable method by replacing antibody-DNA conjugates with nanoparticles which create ultradetectable PCR templates by capturing biotinylated oligonucleotides and catalyzing ligation. A competitive PCR readout was used to make the assay quantitative. We have demonstrated that NP-PLA can detect and quantitate human chorionic gonadotropin (hCG) levels as low as 2.6 fM (?0.1 pg/mL), nearly 1000 times more sensitive than the current state of the art ELISA.

SUBMITTER: Chen H 

PROVIDER: S-EPMC6209106 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature