FRET-Created Traffic Light Immunoassay Based on Polymer Dots for PSA Detection

Abstract

There have been enormous efforts for developing the next generations of fluorometric lateral flow immunochromatographic strip (ICTS) owing to the great advances in fluorescent materials in these years. Here we developed one type of fluorometric ICTS based on ultrabright semiconducting polymer dots (Pdots) in which the traffic light-like signals were created by energy transfer depending on the target concentration. This platform was successfully applied for qualitatively rapid screening and quantitatively precise analysis of prostate-specific antigen (PSA) in 10 min from merely one drop of the whole blood sample. This FRET-created traffic light ICTS possesses excellent specificity and an outstanding detection sensitivity of 0.32 ng/mL for PSA. Moreover, we conducted proof-of-concept experiments to demonstrate its potential for multiplexed detection of cancer biomarkers at the same time in an individual test strip by taking advantage of the traffic light signals. To the best of our knowledge, it is the first model of a traffic light-like immunoassay test strip based on Pdots with multiplexing ability. These results would pave an avenue for designing the next generation of point-of-care diagnostics.

Tuning Iron Spin State in Single-Atom Nanozymes Enables Efficient Peroxidase Mimicking

“…Also, the sensitivity towards PSA is much higher than those of previous reports, suggesting that FeNC-Pd NC hold great promise in immunoassay. (Table S6) 13,49,[52][53][54] For the speci city, obvious characteristic intensity can be observed for PSA, while there are almost no changes for a series of other biomarkers or metal ions compared to blank samples (Figure 5c). In the presence of all of the above interferents, the FeNC-Pd NC ELISA still maintains the signal values towards PSA, indicating its good selectivity and anti-interference ability.…”

“…In a proof-of-principle demonstration, FeNC-Pd NC was applied as labels to colorimetric enzyme-linked immunosorbent assay (ELISA) and prostate-speci c antigen (PSA, a biomarker of prostate cancer) was chosen as a model analyte (Figure 5a). [49][50] For comparison, HRP was also used to establish the HRP-ELISA. 51 Typically, the surface of FeNC-Pd NC is positively charged, which can conjugate with the labeling antibody of PSA (Ab 2 ) as signal tags through electrostatic interaction (Figure S19).…”

Traffic light type paper-based analytical device for intuitive and semi-quantitative naked-eye signal readout

“…Another example is a lateral flow immunochromatographic strip based on fluorescence readout. 26 In addition to requiring an excitation light source, the colour transitions from green over yellow to red are of a gradient nature and final quantitative results must be obtained through color intensity analysis.…”

Ratiometric Fluorescent Lateral Flow Immunoassay for Point‐of‐Care Testing of Acute Myocardial Infarction

“…[17] However,the utilization of double-signalresponsive strategy for the detection of protein biomarkers is still scarce,a lthough it possesses ah igh sensitivity for visualization and is achievable via the energy transfer model. [18] In this work we report aratiometric fluorescence strategy for designing highly sensitive FLFIA (designated as RFLFIA) with hue signal readout. TheRFLFIA strip enabled us to accomplish either naked eye readout of specific concentration of H-FABP or highly sensitive quantification of H-FABP with smartphone.A ss hown in Figure 1( top panel), the fluorescent silica nanosphere loaded with AuNPs and red-light emitting CdSe/CdS/ZnS QDs (rQDs) (designated as SAQ) and tagged with anti-FABP 10E1 antibody (mAb1) is buried in the conjugate pad of test strip,meanwhile green-light emitting CdZnSe/CdS/ZnS QDs (gQDs) conjugated with anti-FABP 28 antibody (mAb2) (designated as mAb2-gQD) is immobilized in the test-line (T-line).…”