Fox Joseph, Batchelor Damien V B, Roberts Holly, Moorcroft Samuel C T, Valleley Elizabeth M A, Coletta Patricia Louise, Evans Stephen D
Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom.
Leeds Institute of Medical Research, Wellcome Trust Brenner Building, St James's University Hospital, Leeds LS9 7TF, United Kingdom.
ACS Appl Nano Mater. 2023 Sep 19;6(19):17769-17777. doi: 10.1021/acsanm.3c03053. eCollection 2023 Oct 13.
Colorectal cancer is the third most common malignancy and the second leading cause of cancer death globally. Multiple studies have linked levels of carcinoembryonic antigen in patient serum to poor disease prognosis. Hence, the ability to detect low levels of carcinoembryonic antigen has applications in earlier disease diagnosis, assessment, and recurrence monitoring. Existing carcinoembryonic antigen detection methods often require multiple reagents, trained operators, or complex procedures. A method alleviating these issues is the lateral flow assay, a paper-based platform that allows the detection and quantification of target analytes in complex mixtures. The tests are rapid, are point-of-care, possess a long shelf life, and can be stored at ambient conditions, making them ideal for use in a range of settings. Although lateral flow assays typically use spherical gold nanoparticles to generate the classic red signal, recent literature has shown that alternate morphologies to spheres can improve the limit of detection. In this work, we report the application of alternative gold nanoparticle morphologies, gold nanotapes (∼35 nm in length) and gold nanopinecones (∼90 nm in diameter), in a lateral flow assay for carcinoembryonic antigen. In a comparative assay, gold nanopinecones exhibited a ∼2× improvement in the limit of detection compared to commercially available spherical gold nanoparticles for the same antibody loading and total gold content, whereas the number of gold nanopinecones in each test was ∼3.2× less. In the fully optimized test, a limit of detection of 14.4 pg/mL was obtained using the gold nanopinecones, representing a 24-fold improvement over the previously reported gold-nanoparticle-based carcinoembryonic antigen lateral flow assay.
结直肠癌是全球第三大常见恶性肿瘤，也是癌症死亡的第二大主要原因。多项研究已将患者血清中的癌胚抗原水平与不良疾病预后联系起来。因此，检测低水平癌胚抗原的能力在疾病早期诊断、评估和复发监测中具有应用价值。现有的癌胚抗原检测方法通常需要多种试剂、经过培训的操作人员或复杂的程序。一种缓解这些问题的方法是横向流动分析，这是一种基于纸张的平台，可对复杂混合物中的目标分析物进行检测和定量。这些检测快速、即时可用、保质期长且可在环境条件下储存，使其非常适合在一系列环境中使用。尽管横向流动分析通常使用球形金纳米颗粒来产生经典的红色信号，但最近的文献表明，球体的替代形态可以提高检测限。在这项工作中，我们报告了替代金纳米颗粒形态，即金纳米带（长度约35nm）和金纳米松果（直径约90nm），在癌胚抗原横向流动分析中的应用。在一项比较分析中，对于相同的抗体负载量和总金含量，与市售球形金纳米颗粒相比，金纳米松果的检测限提高了约2倍，而每次测试中金纳米松果的数量减少了约3.2倍。在完全优化的测试中，使用金纳米松果获得的检测限为14.4pg/mL，比先前报道的基于金纳米颗粒的癌胚抗原横向流动分析提高了24倍。
