A Self-Contained Chemiluminescent Lateral Flow Assay for Point-of-Care Testing

Abstract

Immunoassays whose readouts rely on chemiluminescence are increasingly useful for a broad range of analytical applications, but they are rarely made into point-of-care (POC) format because of the complex reagents required (some reagents have to be stored in low temperatures, and some reagents have to be freshly made right before the assay). This study reports a self-contained chemiluminescent lateral flow assay (CLFA), which prestores all necessary reagents. This CLFA contains three parts: the normal lateral flow assay (LFA) strip, the chemiluminescence substrate pad, and the polycarbonate (PC) holder. On the LFA strip, we simultaneously labeled horseradish peroxidase (HRP) and antibody on the gold nanoparticles (AuNPs) for the conjugate pad. For the substrate pad, we used sodium perborate as the oxidant and lyophilized the chemiluminescence substrate on the glass fiber, which allows long-term storage. After the transfer of substrate from the substrate pad to the nitrocellulose (NC) membrane, we captured the chemiluminescence signal for the quantification of the targets. The HRP on the AuNPs can amplify the chemiluminescence signal efficiently. We used this CLFA system to detect both macromolecules and small molecules successfully. This self-contained and easily processable device is exceedingly appropriate for rapid detection and is a convenient platform for POC testing.

Microfluidics for Biomedical Analysis

“…The normal LFA strip is employed for colorimetric assay using antibody‐Au‐HRP conjugates as the readout, while the substrate pad is used for the storage of the mixture of chemiluminescence substrates. Following the colorimetric detection, the cover of substrate pad onto the LFA strip allows for the chemiluminescence assay of targets (Figure b) . The combination of microfluidic systems with other detection techniques, such as SPR, fluorescence imaging, may extend the application of microfluidic technology for cancer‐related biomarkers analysis.…”

“…The transfer of chemiluminescence substrates to a normal LFA strip will result in chemiluminescence. Reproduced with permission . Copyright 2018, American Chemical Society.…”

Advances in Reagents Storage and Release in Self‐Contained Point‐of‐Care Devices

“…However, H 2 O 2 -liminol needs to be stored separately at low temperature and mixed in situ, which may restrict its applications in POC areas. Recently, researchers reported a self-contained chemiluminescent lateral flow assay (CLFA) for POC testing [40] Adv. Mater.…”

Rapid, quantitative and ultra-sensitive detection of cancer biomarker by a SERRS-based lateral flow immunoassay using bovine serum albumin coated Au nanorods

“…4,5 The methods currently used to detect cancer biomarkers mainly include chemiluminescent immunoassay, enzyme-linked immunosorbent assay (ELISA), immuno-blotting, electrochemical immunoassay, and time-resolved uorescence immunoassay. [6][7][8][9][10] Although these methods are well elaborated and widely used in clinical laboratories, they still exhibit shortcomings, such as tedious operation process, long testing time, and the use of expensive equipment or unstable reagents, in real-time detection of biomarkers. These drawbacks have hindered their wide pointof-care testing (POCT) applications, particularly in lowresource settings, such as clinics, inrmaries, and homes.…”