Multiplexed detection of Fe3+, cobalamin and folate using fluorescent nanoprobe-based microarrays and a smartphone

Multiplexed detection of Fe³⁺, cobalamin and folate using fluorescent nanoprobe-based microarrays and a smartphone

Liu, Z. G.; Xiao, M.; Yang, R. Z.; Zhou, Q. Q.; Ye, H. F.; Yi C. Q*

Journal of Analysis and Testing, 2021, 5, 19-29

?https://doi.org/10.1007/s41664-021-00163-2

Abstract. This work reports on a smartphone-based quantitative POCT system which consists of a paper-based microarray chip, a homemade LEGO dark-box, and a smartphone installed with custom-designed FChip-APP, for on-site quantitation of Fe³⁺, Vitamin 12 (VB₁₂), and folic acid (FA). Collection and automatic analysis of fluorescence turn-off response of three kinds of fluorescent nanoprobes which are coated onto filter papers by a smartphone-based device is the principle behind this study. The POCT system exhibits good analytical performance for multiplexed analysis of Fe³⁺, VB₁₂ and FA with a wide linear range (Fe³⁺, 1.0–14.0 μg mL⁻¹ (R² = 0.983); VB₁₂, 1.35–40.0 μg mL⁻¹ (R² = 0.991); FA, 2.0–26.0 μg mL⁻¹ (R² = 0.994)) and low detection limit (Fe³⁺, 0.35 μg mL⁻¹; VB₁₂, 0.47 μg mL⁻¹; FA, 0.56 μg mL⁻¹). The cost and weight of the whole system are ~ $220 and ~ 600 g per set, highlighting its cost-effectiveness and portability. The simple operation procedures and user-friendly interface of the FChip-APP validate the ease-of-use feature of the reported system. This versatile smartphone-based quantitative POCT system provides a cost-effective and easy-of-use method for screening the context-specific causes of anemia and thus its effective interventions in the future, especially in resource-limited areas.