Aptamer-based fluorescence-quenching lateral flow strip for rapid detection of mercury (II) ion in water samples

Abstract

Divalent mercury ion (Hg) is one of the most common and stable forms of mercury pollution. In this study, a skillfully designed lateral flow strip (LFS) was developed for sensitive detection of Hg in river water samples. Aptamer, a specific oligonucleotide probe, was used to selectively identify and target Hg instead of antibody in traditional immunechromatographic strips; and the fluorescence-quenching system was used to generate positive and low background florescence signals in the competitive-likely LFS. The linear detection range of the LFS for Hg was 0.13 ng mL to 4 ng mL and the limit of detection (LOD) was 0.13 ng mL. This test provided results in 15 min and demonstrated high specificity. For detection of Hg in river water, the results were consistent with inductively coupled plasma-mass spectrometry measurements. The aptamer-based fluorescence-quenching LFS was shown to provide a reliable, accurate method for rapid detection of mercury contamination. Graphical Abstract The principle of the aptamer-based fluorescence-quenching LFS.

Temperature-controlled ionic liquid dispersive liquid–liquid microextraction combined with fluorescence detection of ultra-trace Hg2+ in water

“…17 It has been extensively applied for the determination of heavy metal ions, such as copper, lead, cadmium and mercury. 18,19 The designed uorescent probes are mainly based on rhodamine, 20 boron-dipyrromethene, 21 thymine, 22 noble metal nanoparticles, 23 and quantum dots. 24 Chen et al proposed novel Hg 2+ sensors using tetraphenylethene derivatives as donors and a rhodamine core as the acceptor with high energy transfer efficiency.…”

A signal amplification system on a lateral flow immunoassay detecting for hepatitis e‐antigen in human blood samples

“…The measured signal intensity matched with the machine's image (Figure A and B). The ratio of intensity in test line ( I T ) to intensity in control line ( I C ) ( I T / I C ) was used to replace intensity of T‐line to avoid sample disturbance, humidity, and photographing, and so forth, which might have some effect on the signal of T‐line . The reaction intensity ratio histograms of SAS‐LFIA and cLFIA suggested that the I T / I C values of SAS‐LFIA were much higher than those of cLFIA (Figure C), and had good repeatability.…”

Practical Application of Aptamer-Based Biosensors in Detection of Low Molecular Weight Pollutants in Water Sources

“…Thus, this type of aptasensor is more suitable for real-time detection [ 38 ]. The highly flexible structure of aptamers is suitable for construction of different types of fluorescent sensing devices, including molecular beacons, duplex structure with complementary sequences, structure switching, and competitive laser-based lateral flow assays [ 39 , 40 , 41 , 42 ]. An increasing number of fluorescence-base aptasensors has been used for monitoring low molecular weight pollutants in water sources, such as graphene oxide (GO)-based fluorescence resonance energy transfer (FRET) assay [ 43 ], magnetic bead composites coated with gold nanoparticles (AuNPs) and nicking enzyme fluorescence assay [ 44 ], carbon nanotubes (CNTs)-based fluorescent assay [ 45 , 46 ], biocompatible graphene quantum dots (QDs)-based fluorescent nanosensor [ 47 ].…”

“…Currently, many types of aptasensors were developed for detecting the Hg 2+ in water samples based on the different platforms, including electrochemistry, colorimetric and fluorescence-based analysis [ 73 , 74 , 75 ]. In addition, many signal amplification modes or novel platforms such as chemiluminescence (CL) [ 73 ], electrically rGO-based chemiresistor [ 69 ], silicon nanomaterials (SiNPs)-based fluorescence [ 70 ], fluorescence lateral flow strip [ 40 ] and exothermic chip [ 71 ] have also been developed for detecting the Hg 2+ in water samples. Among those, a simple and rapid CL aptasensor for Hg 2+ was developed in natural water samples with a limit of detection (LOD) of 16 pM within 30 min.…”