Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
Analyst. 2021 Apr 26;146(8):2726-2733. doi: 10.1039/d0an02293d.
The traditional gold-nanoparticle-based lateral flow immunoassay (LFIA) cannot satisfy the requirements for the sensitive detection of dehydroepiandrosterone (DHEA) in human urine. To enhance the sensitivity of the LFIA, platinum-iridium nanocubes (Pt-Ir NCs) with high catalytic efficiency and stability were synthesized and labelled with polyclonal antibody (pAb) to form a pAb-Pt-Ir probe. For the detection of DHEA, a novel LFIA with Pt-Ir NCs as an optical label and an enhanced LFIA in which the peroxidase-like activity of the Pt-Ir NCs was triggered by the introduction of the chromogenic substrate 3-amino-9-ethyl-carbazole (AEC) were developed and compared with a LFIA with platinum nanocubes (PtNCs) as an optical label. The visual limit of detection was 0.5 ng mL-1 for Pt-Ir-LFIA and 0.05 ng mL-1 for AEC-enhanced Pt-Ir-LFIA, in comparison to 100 ng mL-1 for PtNCs-LFIA and 50 ng mL-1 for AEC-enhanced PtNCs-LFIA. The average recoveries from spiked urine samples ranged from 90.8% to 110.4%, with a coefficient of variation below 12.6%, suggesting the accuracy and reliability of our developed immunoassay. Achieving excellent sensitivity, specificity, and reproducibility, Pt-Ir-LFIA provided a promising platform for monitoring DHEA.
传统的基于金纳米颗粒的侧向流动免疫分析（LFIA）不能满足人体尿液中脱氢表雄酮（DHEA）灵敏检测的要求。为了提高 LFIA 的灵敏度，合成了具有高效催化稳定性的铂铱纳米立方体（Pt-Ir NCs），并用多克隆抗体（pAb）标记形成 pAb-Pt-Ir 探针。用于检测 DHEA，开发了一种新型 LFIA，其中 Pt-Ir NCs 用作光学标记，并且通过引入显色底物 3-氨基-9-乙基咔唑（AEC）触发 Pt-Ir NCs 的过氧化物酶样活性，与以铂纳米立方体（PtNCs）作为光学标记的 LFIA 进行了比较。Pt-Ir-LFIA 的视觉检测限为 0.5 ng mL-1，AEC 增强的 Pt-Ir-LFIA 的检测限为 0.05 ng mL-1，而 PtNCs-LFIA 的检测限为 100 ng mL-1，AEC 增强的 PtNCs-LFIA 的检测限为 50 ng mL-1。从尿液样本中添加的回收率平均在 90.8%至 110.4%之间，变异系数低于 12.6%，表明我们开发的免疫分析具有准确性和可靠性。Pt-Ir-LFIA 实现了出色的灵敏度、特异性和重现性，为监测 DHEA 提供了有前途的平台。
