Department of Clinical Laboratory, Dalang Hospital, Dongguan, China.
Kingfocus Biomedical Engineering Co., Ltd, Shenzhen, China.
J Clin Lab Anal. 2021 May;35(5):e23752. doi: 10.1002/jcla.23752. Epub 2021 Mar 24.
Interleukin-6 (IL-6) is an inflammatory factor that increases rapidly in response to infectious diseases including sepsis. The aim of this study is to develop a quantum dot (QD)-based fluorescence lateral flow immunoassay (LFIA) strip that can rapidly and accurately detect IL-6 levels.
QD-based LFIA strips were fabricated by conjugating CdSe/ZnS QDs to the IL-6 antibody. Performance verification and clinical sample analysis were carried out to evaluate the newly developed strip.
QD-based LFIA strips were successfully fabricated. The test strip's linear range was 10-4000 pg/ml, with a linear correlation coefficient of R ≥ .959. The sensitivity of the test strip was 1.995 pg/ml. The recovery rate was 95.72%-102.63%, indicating satisfying accuracy. The coefficient of variation (CV) of the intra-assay was 2.148%-3.903%, while the inter-assay was 2.412%-5.293%, verifying the strip's high precision. The cross-reaction rates with various interleukins (IL-1α, IL-1β, IL-2, IL-4, and IL-8) and interferon-γ (IFN-γ) were all <0.1%. When the strip was placed in a 50°C oven for 1, 2, 3, and 4 weeks, the test results were not significantly altered compared to storage at room temperature. Furthermore, 200 clinical serum samples were analyzed to compare the strip with the Beckman chemiluminescence immunoassay (CLIA) kit, which revealed a high correlation (n = 200, R = .9971) for the detection of IL-6.
The QD-based test strip can rapidly and quantitatively detect IL-6 levels, thus meeting the requirement of point-of-care test (POCT) and showing excellent clinical prospects.
白细胞介素-6（IL-6）是一种炎症因子，在感染性疾病（包括败血症）时迅速增加。本研究旨在开发一种基于量子点（QD）的荧光侧向流动免疫分析（LFIA）试纸，能够快速、准确地检测 IL-6 水平。
通过将 CdSe/ZnS QD 与 IL-6 抗体偶联，制备基于 QD 的 LFIA 试纸。通过性能验证和临床样本分析来评估新开发的试纸。
成功制备了基于 QD 的 LFIA 试纸。该测试条的线性范围为 10-4000pg/ml，线性相关系数 R≥0.959。测试条的灵敏度为 1.995pg/ml。回收率为 95.72%-102.63%，表明具有令人满意的准确性。批内变异系数（CV）为 2.148%-3.903%，批间变异系数为 2.412%-5.293%，证明了该试纸具有较高的精密度。与各种白细胞介素（IL-1α、IL-1β、IL-2、IL-4 和 IL-8）和干扰素-γ（IFN-γ）的交叉反应率均<0.1%。当试纸在 50°C 烤箱中放置 1、2、3 和 4 周时，与在室温下储存相比，测试结果没有明显变化。此外，分析了 200 例临床血清样本，将该试纸与贝克曼化学发光免疫分析（CLIA）试剂盒进行比较，检测 IL-6 的相关性较高（n=200，R=0.9971）。
基于 QD 的测试条可以快速、定量地检测 IL-6 水平，因此满足即时检测（POCT）的要求，具有良好的临床前景。
