- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Ratiometric fluorescent sensing system for drug residue analysis: Highly sensitive immunosensor using dual-emission quantum dots hybrid and compact smartphone based-device
摘要： Immunoassays such as the enzyme-linked immunosorbent assay (ELISA) are utilized extensively for detecting protein biomarkers and small molecules in healthcare, environmental monitoring, and food analysis. Unfortunately, the current strategies for immunoassays often require sophisticated apparatus such as a microplate reader, which might not be available in resource-limited areas. To mitigate this problem, we designed a compact smartphone based-device and a multicolor response immunosensor. First, we designed a compact and cost-effective 3D-printed attachment, where a light-emitting diode was used as a light excitation source and a smartphone captured the fluorescent emission signals. Second, by combining quantum dots hybrid and chemical redox reaction, multiple color responses were displayed in the presence of the analyte at different concentrations. Third, solutions with distinct tonality could be readily distinguished by the naked eye and they were suitable for quantitative analysis using the hue-saturation-lightness color space based on a smartphone application. The versatility of the proposed sensing system was demonstrated by implementing an indirect competitive ELISA for analyzing trace drug residues in foodstuffs. The multicolor response of this sensing strategy allows us to visually quantify drug residues in foodstuffs. Moreover, the smartphone-based immunosensor can assess the exact concentration of the analyte by using a self-designed mobile application. The proposed assay provides a highly sensitive performance that the limit of detection was 0.37 ng/mL by visual detection and 0.057 ng/mL using the compact device. Due to its advantages in terms of portability, straightforward visual detection, high sensitivity, and cost effectiveness, the proposed immunosensor has great potential for applications in areas without access to laboratories or expensive infrastructure.
关键词： Quantum Dots Hybrid,Compact Device,Visual Readout,Immunosensor,Residue Analysis
更新于2025-09-12 10:27:22
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Photothermal Microfluidic Sensing Platform Using Near-Infrared Laser-Driven Multiplexed Dual-Mode Visual Quantitative Readout
摘要： The application of different sensing principles in microfluidic devices opens up further possibilities for the development of point-of-care testing (POCT). Herein, the photothermal sensing principle is introduced in microfluidic paper-based analytical devices (μPADs) to develop a photothermal microfluidic sensing platform using near-infrared (NIR) laser-driven multiplexed dual-mode visual quantitative readout. Prussian blue (PB) as the analyte-associated photothermal agent was in-situ synthesized in thermoresponsive poly(N-isopropylacrylamide) hydrogels to serve as the on-chip photothermal sensing element. NIR laser-driven photothermal effect of PB triggered not only on-chip dose-dependent heat generation but also phase transition-induced dye release from the hydrogels, simultaneously enabling both thermal image- and distance-based dual-mode visual quantitative readout of the analyte concentration in a multiplexed manner. Both the on-chip temperature elevation value of the hydrogels and the traveling distance of released dye solutions were proportional to the concentration of PB. Using the detection of silver ions in environmental water as a proof-of-concept study, the photothermal μPAD can detect silver ions at a concentration as low as 0.25 μM with high selectivity and satisfactory accuracy. The photothermal microfluidic sensing platform holds great potential for POCT with promising integratability and broad applicability, owing to the combination of synergistic advantages of the photothermal sensing principle, μPADs and photothermally responsive hydrogels.
关键词： Microfluidic device,Photothermal effect,Visual readout,Point-of-care testing,Thermoresponsive hydrogel
更新于2025-09-11 14:15:04