Institute of Applied Mechanics, National Taiwan University, Taipei, 106, Taiwan.
Department of Orthopaedic Surgery, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taoyuan, 333, Taiwan.
Biosens Bioelectron. 2025 Jan 1;267:116849. doi: 10.1016/j.bios.2024.116849. Epub 2024 Oct 11.
The lateral flow immunoassay (LFIA) is predominant in rapid diagnostic tests owing to its cost-effectiveness and operational simplicity. However, the conventional LFIA exhibits limited sensitivity and is susceptible to human variance for the result readout, impacting result interpretation. In this study, we introduced a novel one-step copper deposition-induced signal amplification lateral flow immunoassay (osa-LFIA) that markedly enhances the detection sensitivity for Staphylococcus aureus (protein A) and Pseudomonas aeruginosa (exotoxin A). Utilizing gold nanoparticles (AuNPs) as a catalyst, this approach employs ascorbic acid to reduce Cu to Cu, depositing on AuNPs at the test line and amplifying the signal. A user-friendly design features a three-dimensional paper structure incorporating pre-dried reagents, enabling a streamlined, efficient testing process. The osa-LFIA significantly lowers detection limits to 3 ng mL for protein A and 10 ng mL for exotoxin A, offering a tenfold improvement over conventional LFIA. Additionally, we developed a portable grayscale detection device, achieving less than 10% error in quantitative analysis compared to the data acquired and analyzed in the lab. This entire process, from detection to signal amplification, is completed in just 20 min. For the clinical trial, we utilized the osa-LFIA to test synovial fluid samples infected with Staphylococcus aureus. We also successfully detected different concentrations of the exotoxin A in parallel, with a recovery value of 96%-110%. Our findings demonstrate the osa-LFIA's potential as a rapid, highly sensitive, and simple-to-use diagnostic tool for detecting various pathogens, significantly advancing the field of rapid diagnostic testing.
侧向流动免疫分析（LFIA）因其具有成本效益和操作简单的特点，在快速诊断测试中占据主导地位。然而，传统的 LFIA 表现出有限的灵敏度，并且容易受到人为因素的影响，导致结果读取出现差异，从而影响结果解释。在本研究中，我们引入了一种新颖的一步铜沉积诱导信号放大侧向流动免疫分析（osa-LFIA），该方法显著提高了对金黄色葡萄球菌（蛋白 A）和铜绿假单胞菌（外毒素 A）的检测灵敏度。该方法利用金纳米颗粒（AuNPs）作为催化剂，采用抗坏血酸将 Cu 还原为 Cu，在测试线上沉积在 AuNPs 上并放大信号。该方法采用了一种用户友好的三维纸结构设计，其中包含预干燥的试剂，使整个检测过程更加高效。osa-LFIA 将检测限显著降低至蛋白 A 的 3ng mL 和外毒素 A 的 10ng mL，比传统 LFIA 提高了 10 倍。此外，我们还开发了一种便携式灰度检测设备，与实验室中获取和分析的数据相比，其定量分析的误差小于 10%。从检测到信号放大，整个过程仅需 20 分钟即可完成。在临床试验中，我们使用 osa-LFIA 检测感染金黄色葡萄球菌的滑液样本。我们还成功地平行检测了不同浓度的外毒素 A，回收率为 96%-110%。我们的研究结果表明，osa-LFIA 具有作为一种快速、高灵敏度和易于使用的诊断工具的潜力，可用于检测各种病原体，为快速诊断测试领域带来了显著的进展。
