Faculty of Science, Department of Chemistry, Ferdowsi University of Mashhad, Mashhad, 9177948974, Iran.
Sci Rep. 2023 Aug 22;13(1):13712. doi: 10.1038/s41598-023-40871-6.
During the outbreak of coronavirus, RT-PCR was the premier gold standard method for severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) diagnosis. However, the sophisticated procedure of RT-PCR persuades researchers to develop sustainable point-of-need immunoassay methods for tracing unwitting carriers of SARSCoV-2. Herein, by fabricating a modified polysulfone (MPSF) membrane, we developed an integrated radial flow immunoassay (IRFIA) platform as a point-of-care system, capable of multiplying the immunoassays at a short run time. The target molecule is the SARSCoV-2 IgM in separated plasma. Although the lateral flow immunoassay kits for the rapid identification of Covid-19 have already been commercially developed but, the proposed method is superior to the conventional lateral flow immunoassay. In the newly designed membrane system, we have combined the five membranes of prevalent lateral flow immunoassay (LFIA) strips in one polymeric membrane. The MPSF membrane is capable of separating plasma from whole blood sample, which will reduce the interference of red colour of hemoglobin with generated signal and enhance the immunoassay precision. The efficiency of plasma separation, reached the mean value of 97.34 v/v% in 5 s. Furthermore, the gel electrophoresis results of the separated plasma contrasted with centrifuged plasma sample, demonstrated more efficient separation by the membrane. Using the MPSF membrane, signal generation time reduced from about 20 min in conventional rapid test strip for Covid-19 to about 7 min in IRFIA platform. The sensitivity and specificity of the membrane platform were determined to be 89% and 90%, respectively and a Kappa coefficient of 0.79 showed reliable agreement between the RT-PCR and the membrane system.
在冠状病毒爆发期间，逆转录聚合酶链反应（RT-PCR）是严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）诊断的首要金标准方法。然而，RT-PCR 的复杂程序促使研究人员开发可持续的即时免疫测定方法来追踪 SARS-CoV-2 的无症状携带者。在这里，我们通过制造改性聚砜（MPSF）膜，开发了一种集成的径向流动免疫分析（IRFIA）平台作为即时检测系统，能够在短时间内实现免疫分析的倍增。目标分子是分离血浆中的 SARS-CoV-2 IgM。虽然已经开发出用于快速识别 Covid-19 的侧向流动免疫测定试剂盒，但所提出的方法优于传统的侧向流动免疫测定。在新设计的膜系统中，我们将流行的侧向流动免疫测定（LFIA）条的五个膜组合在一个聚合物膜中。MPSF 膜能够将血浆从全血样品中分离出来，这将减少血红蛋白的红色对产生信号的干扰，并提高免疫分析的精度。血浆分离效率在 5 秒内达到 97.34 v/v%的平均值。此外，分离血浆的凝胶电泳结果与离心血浆样品对比，证明膜的分离效率更高。使用 MPSF 膜，信号生成时间从传统的快速测试条检测 Covid-19 的约 20 分钟缩短到 IRFIA 平台的约 7 分钟。膜平台的灵敏度和特异性分别为 89%和 90%，RT-PCR 和膜系统之间的 Kappa 系数为 0.79，表明可靠的一致性。
