{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Zhou X"],"funding":["Arizona State University/Mayo Clinic Collaborative Research Seed Grant","Mayo Clinic","NIGMS NIH HHS","National Institute of General Medical Sciences of National Institute of Health"],"pagination":["e05207"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC12376538"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["12(31)"],"pubmed_abstract":["Single-molecule immunoassay is a reliable technique for the detection and quantification of low-abundance blood biomarkers, which are essential for early disease diagnosis and biomedical research. However, current single-molecule methods predominantly rely on endpoint detection and necessitate signal amplification via labeling, which brings a variety of unwanted effects, like matrix effect and autofluorescence interference. This study introduces a real-time mass imaging-based label-free single-molecule immunoassay (LFSMiA). Featuring plasmonic scattering microscopy-based mass imaging, a 2-step sandwich assay format enables background reduction, minimization of matrix effect by dynamic tracking of single binding events, and fully leveraging real-time data for improved measurement precision through a Bayesian Gaussian process model, the LFSMiA enables ultra-sensitive and direct protein detection at the single-molecule level in neat blood sample matrices. LFSMiA measurement is demonstrated for interleukin-6 and prostate-specific antigen in buffer, undiluted serum, and whole blood with sub-femtomolar detection limits and eight logs of dynamic ranges. Moreover, comparable performance is achieved with an inexpensive miniaturized setup. To show its translational potential to clinical settings and point-of-care diagnostics, N-terminal pro-B-type natriuretic peptide is examined in patient whole blood samples using the LFSMiA and results in a strong linear correlation (r > 0.99) with standard clinical lab results."],"journal":["Advanced science (Weinheim, Baden-Wurttemberg, Germany)"],"pubmed_title":["Label-Free Single-Molecule Immunoassay."],"pmcid":["PMC12376538"],"funding_grant_id":["ARI-285360-01","SPA00007255/ARI-333334","R01GM140193","R01 GM140193"],"pubmed_authors":["Jiang J","Snozek CLH","Zhou S","Wang S","Wan Z","Braswell B","Chen C","Yang EH","Zhou X","Chemerkouh MJHN","Ma G"],"additional_accession":[]},"is_claimable":false,"name":"Label-Free Single-Molecule Immunoassay.","description":"Single-molecule immunoassay is a reliable technique for the detection and quantification of low-abundance blood biomarkers, which are essential for early disease diagnosis and biomedical research. However, current single-molecule methods predominantly rely on endpoint detection and necessitate signal amplification via labeling, which brings a variety of unwanted effects, like matrix effect and autofluorescence interference. This study introduces a real-time mass imaging-based label-free single-molecule immunoassay (LFSMiA). Featuring plasmonic scattering microscopy-based mass imaging, a 2-step sandwich assay format enables background reduction, minimization of matrix effect by dynamic tracking of single binding events, and fully leveraging real-time data for improved measurement precision through a Bayesian Gaussian process model, the LFSMiA enables ultra-sensitive and direct protein detection at the single-molecule level in neat blood sample matrices. LFSMiA measurement is demonstrated for interleukin-6 and prostate-specific antigen in buffer, undiluted serum, and whole blood with sub-femtomolar detection limits and eight logs of dynamic ranges. Moreover, comparable performance is achieved with an inexpensive miniaturized setup. To show its translational potential to clinical settings and point-of-care diagnostics, N-terminal pro-B-type natriuretic peptide is examined in patient whole blood samples using the LFSMiA and results in a strong linear correlation (r > 0.99) with standard clinical lab results.","dates":{"release":"2025-01-01T00:00:00Z","publication":"2025 Aug","modification":"2026-05-09T17:50:58.898Z","creation":"2026-04-08T01:08:50.981Z"},"accession":"S-EPMC12376538","cross_references":{"pubmed":["40538199"],"doi":["10.1002/advs.202505207"]}}