Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
Analyst. 2021 Jul 26;146(15):4796-4802. doi: 10.1039/d1an01052b.
Quantum dot (QD)-encoded microbeads as optical barcode with high fluorescence intensity and fluorescence uniformity, excellent stability and dispersity are greatly important for suspension array (SA). However, the size distribution of the microbeads mass-produced by the membrane emulsification method usually shows polydispersity, which leads to obstacles, imposing labour-intensive experimental iterations for the application of fluorescence-encoded microbeads as a distinguishable barcode. Herein, a simple simulation strategy based on a multicolor fluorescence model (MFM) was used to predict the influence of the microbeads' size distribution on the barcode signals. The point L and S respectively represent the two end points of the barcode, and the line segment LS can be considered as a cluster of the QD-encoded microbeads (simulated barcode). Experimental clusters of fluorescent microbeads were found to be in good agreement with the simulated barcodes. This simple simulation strategy can effectively simplify the experimental iteration process because the fluorescence-encoded microbeads are not decoded by a flow cytometer. Moreover, when applied for the high-throughput ultrasensitive detection of three tumor markers (CEA, CA125 and CA199) in a single sample, these barcodes exhibit superior detection performance. Detection limits of 0.028 ± 0.001 ng mL-1 for CEA, 1.5 ± 0.02 KU L-1 for CA125 and 0.8 ± 0.1 KU L-1 for CA199 are achieved, which meet the sensitivity criteria of tumor marker analysis. Therefore, this simple simulation strategy helps to overcome technical and economic obstacles for the widespread application of SA.
量子点（QD）编码微球具有高荧光强度和荧光均匀性、优异的稳定性和分散性，对悬浮阵列（SA）非常重要。然而，通过膜乳化法大规模生产的微球的粒径分布通常表现出多分散性，这导致了障碍，为了将荧光编码微球作为可区分的条码进行应用，需要进行劳动密集型的实验迭代。在此，使用基于多色荧光模型（MFM）的简单模拟策略来预测微球粒径分布对条码信号的影响。点 L 和 S 分别代表条码的两个端点，线段 LS 可以被视为一组 QD 编码微球（模拟条码）。实验荧光微球簇与模拟条码吻合良好。这种简单的模拟策略可以有效地简化实验迭代过程，因为荧光编码微球不需要通过流式细胞仪进行解码。此外，当应用于单个样本中三种肿瘤标志物（CEA、CA125 和 CA199）的高通量超灵敏检测时，这些条码表现出优异的检测性能。CEA 的检测限为 0.028 ± 0.001 ng mL-1，CA125 为 1.5 ± 0.02 KU L-1，CA199 为 0.8 ± 0.1 KU L-1，满足肿瘤标志物分析的灵敏度标准。因此，这种简单的模拟策略有助于克服 SA 广泛应用的技术和经济障碍。
