Advanced Signal-Amplification Strategies for Paper-Based Analytical Devices: A Comprehensive Review

Abstract

Paper-based analytical devices (PADs) have emerged as a promising approach to point-of-care (POC) detection applications in biomedical and clinical diagnosis owing to their advantages, including cost-effectiveness, ease of use, and rapid responses as well as for being equipment-free, disposable, and user-friendly. However, the overall sensitivity of PADs still remains weak, posing a challenge for biosensing scientists exploiting them in clinical applications. This review comprehensively summarizes the current applicable potential of PADs, focusing on total signal-amplification strategies that have been applied widely in PADs involving colorimetry, luminescence, surface-enhanced Raman scattering, photoacoustic, photothermal, and photoelectrochemical methods as well as nucleic acid-mediated PAD modifications. The advances in signal-amplification strategies in terms of signal-enhancing principles, sensitivity, and time reactions are discussed in detail to provide an overview of these approaches to using PADs in biosensing applications. Furthermore, a comparison of these methods summarizes the potential for scientists to develop superior PADs. This review serves as a useful inside look at the current progress and prospective directions in using PADs for clinical diagnostics and provides a better source of reference for further investigations, as well as innovations, in the POC diagnostics field.

Unclearing Microscopy

“…To unclear biological samples using in situ polymerization, we used a strategy called photopolymerization-based signal amplification (PBA). PBA is commonly used to amplify signals from antibody-antigen interactions in immunoassays (Hoang et al, 2021). In these assays, antigens bind to immobilized antibodies and are then mixed with photoinitiator-conjugated capture antibodies.…”

Printable biosensors towards next-generation point-of-care testing: paper substrate as an example

“…Signal-amplification strategies in PADs could be mainly divided into nanomaterial-based, nucleic acid-based, and PADs based signal amplifications. 46 b ,200 A detailed and comprehensive review of the signal amplification strategies for paper-based devices is summarized by Liu and her colleagues. 46 b Here we will just briefly summarize the nanomaterial-based signal amplification and nucleic acid-based signal amplification strategies that could be applied to printable paper-based biosensors.…”

Research progress on detection techniques for point-of-care testing of foodborne pathogens

“…At present, constant temperature amplification techniques applied to foodborne pathogenic microorganisms mainly include loop-mediated isothermal amplification (LAMP), recombinant enzyme-mediated nucleic acid amplification (RAA), RPA, and nucleic acid sequence-dependent amplification (NASBA) ( Chen et al, 2018 ; Khan et al, 2019 ; Safenkova et al, 2020 ; He et al, 2021a ; Hoang et al, 2021 ; Tian et al, 2022 ).…”