ArticleJournal of fluorescence2026
Ultrasensitive de novo Protein Sandwich Lateral flow Fluorescence Assay for Cortisol in Saliva and Serum using Quantum dots and Europium Nanoparticles.
Article in Journal of fluorescence, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
We describe and demonstrate the first lateral flow (LF) sandwich fluorescence assay for the small molecule hormone cortisol, enabled by a pair of de novo-designed cortisol-induced dimerization (CID) proteins. CID proteins C4 and C10, originally characterized in a chemiluminescent format, sandwich a single cortisol molecule between two engineered binding domains, eliminating the inherent sensitivity limitations of traditional competitive small molecule LF assays. In the present assay, C10 was immobilized as the capture reagent on a nitrocellulose membrane, and C4 was conjugated to either streptavidin-coated red quantum dots (QDs) for saliva applications or streptavidin-coated europium chelate-doped polystyrene nanoparticles (Eu NPs) for serum applications. The QD-CID strips produced a visually scored limit of detection (LOD) of 200 pg/mL of cortisol spiked into natural human saliva (20 pg total in a 100 µL sample) and 2 pg/mL in artificial saliva (200 fg total), spanning and extending below the physiological diurnal range of salivary cortisol (approximately 1,000-7,500 pg/mL). A goat anti-avidin control line successfully captured the C4-biotin-streptavidin-QD conjugate after migration, providing flow validation. QDs performed poorly in undiluted human serum, consistent with prior reports of ZnS shell perturbation by serum components. Substituting europium-chelate-doped polystyrene NPs preserved the long Stokes shift advantage while protecting the fluorophore from serum-induced quenching and enabled detection in pooled human serum across a dynamic range of 2-200 ng/mL (200 pg to 20 ng of total cortisol per 100 µL sample), more than spanning the full physiological diurnal range of serum cortisol. The entire LF test is executed in approximately 15 min, requires no cold chain or laboratory instrumentation beyond a handheld UV reader, and is suitable for both point-of-care clinical use and at-home stress and endocrine monitoring.
Indexed as
Identifiers
42364004What 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.