Hue-Recognition Strategy-Based Immunoassay Using Functionalized Dendritic Silica Colloids and Gold Nanoclusters for Point-of-Care Testing of C-Reactive Proteins

Abstract

Considering that hue-recognition has drawn increasing research interests for visual detection because of its high accuracy and flexible analysis modalities, the exploration of a rational hue-recognition sensing system is highly demanded. Here, we report a hue-recognition-based lateral flow immunoassay (HLFIA) by ratiometric modulation of emission from two nanoprobes, in which red-emitting ruthenium(II)-doped dendritic silica colloids and green-emitting gold nanoclusters function as reporter and reference, respectively. The HLFIA strip can generate a visually discernible green-to-orange-red color gradient alternation, enabling the naked-eye semiquantitative inspection of successive C-reactive protein (CRP) concentration and concentration intervals (0–50, 50–150, and 150–500 ng mL–1) with a visual detection limit of 10 ng mL–1. By integrating with a customized smartphone-based portable imaging device and RGB color space recognition, the precise quantification of CRP can be achieved with a linear range of 0–100 ng mL–1 and a limit of detection of 0.64 ng mL–1. The HLFIA strip is robust and validated for CRP detection in real serum, holding great promise for noninstrumental and deprofessionalized point-of-care immunoassay of biomarkers.

CdTe/Silica Nanospheres in a Lateral Flow Immunoassay for Prostate-Specific Antigen

“…The limit of detection (LOD) was calculated to be 0.127 ng/mL. Compared with the reported and commercially available LFIA strips for CRP analysis (Table S2), the current assay performed relatively good. ,, …”

“…Compared with the reported and commercially available LFIA strips for CRP analysis (Table S2), the current assay performed relatively good. 36,46,47 The design and principle of PSA detection using the UQSN are illustrated in Figure 5a. The anti-PSA AB0105-1 and chicken IgY were labeled with UQSN and fixed on the conjugate pad.…”

Semiconductor Nanoplatelets Based Host‐Guest Assembly Structure with High Color Purity for Hue‐Recognizable Lateral Flow Immunoassay

“…This mode is anticipated to enhance the sensitivity by producing a red signal and simultaneously eliminating the existing green reference intensity on T line, leading to an increased signal/reference (R/G) ratio. [8,58] Meanwhile, it extends the linear detection range by substantial eradication of green reference intensity on T line especially at high antigenconcentration-end, resulting in a prominent increase of R/G value. This partially offsets the general hook effect that causing signal saturation (reaching the plateau) or even decrease.…”