Cellular-Beacon-Mediated Counting for the Ultrasensitive Detection of Ebola Virus on an Integrated Micromagnetic Platform

Abstract

Ebola virus (EBOV) disease is a complex zoonosis that is highly virulent in humans and has caused many deaths. Highly sensitive detection of EBOV is of great importance for early-stage diagnosis for increasing the probability of survival. Herein, we established a cellular-beacon-mediated counting strategy for an ultrasensitive EBOV assay on a micromagnetic platform. The detection platform, which was assisted by on-demand magnetic-field manipulation, showed high integration and enhanced complex-sample pretreatment by magnetophoretic separation and continuous-flow washing. Cellular beacons (i.e., fluorescent cells) with superior optical properties were used as reporters, and each cellular beacon was used as a fluorescent tracking unit to quantify EBOV by counting the numbers of individual fluorescent signals on the micromagnetic platform. This method achieves high sensitivity with a detection limit as low as 2.6 pg/mL, and the detection limit shows little difference in a complex matrix. In addition, it has excellent specificity and good reproducibility. These results indicate that this method proposes an ultrasensitive detection strategy for early diagnosis of the disease.

Enrichment–Stowage–Cycle Strategy for Ultrasensitive Electrochemiluminescent Detection of HIV-DNA with Wide Dynamic Range

“…It can be seen from the hysteresis loop (Figure C) that the MBs had superparamagnetism and the saturation magnetization was 24.68 emu/g. Therefore, MBs could be gathered together under the external magnet and also be quickly dispersed into the solution after the magnet was removed. , The capture efficiency of MBs was close to 100% in 120 s on a magnetic scaffold (Figure D), indicating the strong magnetic response ability of MBs and 120 s was selected as the adsorption time of MBs during washing processes. On the basis of the amide bond reaction, H1 was modified to the surface of MBs to fabricate capture probes, and DLS was applied to characterize the modification process (Figure S3A, SI).…”

“…Several effective technologies have been reported to enrich and separate targets from complex samples, including chromatography, magnetic nanobeads (MBs), and capillary electrophoresis. − Among them, MBs have been proven to be a powerful separation tool owing to its large specific surface area, rich functional groups, superparamagnetism, and reaction flexibility. Currently, MBs have been widely used in various analytical methods, including electrochemistry, , fluorescence, − lateral flow immunoassay, microfluidic chip, and ECL , sensors. Therefore, it is interesting to combine the idea of MBs and multiple amplification strategies to construct ECL biosensors with high sensitivity and accuracy.…”

Detection of RNA viruses from influenza and HIV to Ebola and SARS-CoV-2: a review

“…26 Fluorescence is reported as a reproducible method with RSD < 5%. 41 Other uorescencebased methods use nanospheres, micromagnetic platforms, or upconversion materials for creating luminescence, which is further absorbed by nanoparticles conjugated to the target analyte. This method allows for more sensitive detection at the femtomolar level.…”

Advanced Selection Methodologies for DNAzymes in Sensing and Healthcare Applications

“…It has been assumed that reducing the number of target molecules may lead to the identification of aptamers with higher affinity. In addition, the short transit time enhances the applicability of the method, and this microsystem provides a rapid and effective screening protocol for aptamers with potential diagnostic applications [40][41][42].…”