ArticleAnalytical chemistry2023
Digital and Analog Detection of SARS-CoV-2 Nucleocapsid Protein via an Upconversion-Linked Immunosorbent Assay.
Article in Analytical chemistry, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
12 citing papers in PubMed, 45 citations in OpenAlex.
- Beads-on-a-Tip testing for ultrasensitive antigen detection across a large dynamic range.Smart molecules : open access · 2026Article
- Multicolor Upconversion Förster Resonant Energy Transfer Using Optimized Yb@YbTm Core@Shell Nanoparticles.ACS nano · 2025Article
- Nanoparticle-Supported, Rapid, and Electronic Detection of SARS-CoV-2 Antibodies and Antigens at the Subfemtomolar Level.ACS nano · 2025Article
- Recent Progress on Rare-Earth-Doped Upconversion Nanomaterials for Bioassay Applications.Biosensors · 2025Review
- Pushing the Limits of Lateral Flow Immunoassay by Digital SERS for the Ultralow Detection of SARS-CoV-2 Virus.Small science · 2024Article
- Magnetic microbead-based upconversion immunoassay with laser-induced breakdown spectroscopy readout for the detection of prostate-specific antigen.Mikrochimica acta · 2024Article
- Upconversion Nanoparticle-Based Dot-Blot Immunoassay for Quantitative Biomarker Detection.Analytical chemistry · 2024Article
- Development of Detection Antibody Targeting the Linear Epitope in SARS-CoV-2 Nucleocapsid Protein with Ultra-High Sensitivity.International journal of molecular sciences · 2024Article
- Sandwich Immuno-RCA Assay with Single Molecule Counting Readout: The Importance of Biointerface Design.ACS applied materials & interfaces · 2024Article
- A nanogap-enhanced SERS nanotag-based lateral flow assay for ultrasensitive and simultaneous monitoring of SARS-CoV-2 S and NP antigens.Mikrochimica acta · 2024Article
- Bright photon upconversion in LiYbFJournal of colloid and interface science · 2023Article
- Recent Trends in Lateral Flow Immunoassays with Optical Nanoparticles.International journal of molecular sciences · 2023Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 4 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The COVID-19 crisis requires fast and highly sensitive tests for the early stage detection of the SARS-CoV-2 virus. For detecting the nucleocapsid protein (N protein), the most abundant viral antigen, we have employed upconversion nanoparticles that emit short-wavelength light under near-infrared excitation (976 nm). The anti-Stokes emission avoids autofluorescence and light scattering and thus enables measurements without optical background interference. The sandwich upconversion-linked immunosorbent assay (ULISA) can be operated both in a conventional analog mode and in a digital mode based on counting individual immune complexes. We have investigated how different antibody combinations affect the detection of the wildtype N protein and the detection of SARS-CoV-2 (alpha variant) in lysed culture fluid via the N protein. The ULISA yielded a limit of detection (LOD) of 1.3 pg/mL (27 fM) for N protein detection independent of the analog or digital readout, which is approximately 3 orders of magnitude more sensitive than conventional enzyme-linked immunosorbent assays or commercial lateral flow assays for home testing. In the case of SARS-CoV-2, the digital ULISA additionally improved the LOD by a factor of 10 compared to the analog readout.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.