A highly sensitive FET-type aptasensor using flower-like MoS₂ nanospheres for real-time detection of arsenic(iii)

Abstract

Arsenic (As) contamination in drinking water is problematic due to its threat to human health. Highly stable, sensitive and selective sensors are needed for As(iii), which is the most toxic of the various forms of arsenic. Herein, we describe the fabrication of field-effect transistor (FET)-type aptasensors for As(iii) detection that is based on carboxylic polypyrrole (CPPy)-coated flower-like MoS nanospheres (CFMNSs). Arsenic-binding aptamer-conjugated CFMNSs were integrated into a liquid-ion gated FET system, leading to extraordinary performance with a rapid response (on a time scale of less than 1 s). Field-induced current changes occurred through the interaction between the aptamer and As(iii), resulting in sensitive discrimination of As(iii) at unprecedentedly low concentrations (ca. 1 pM). Moreover, the CFMNS-based aptasensor selectively recognized As(iii) among numerous other metal ions and accurately detected As(iii) in a mixed solution. The FET aptasensor could also discriminate target analytes in a real sample derived from river water. This MoS-based aptasensor is a promising tool for the detection of As(iii) and could be used in a wide range of practical applications.

Green synthesis of surface-passivated carbon dots from the prickly pear cactus as a fluorescent probe for the dual detection of arsenic(iii) and hypochlorite ions from drinking water

“…[7][8][9][10] Arsenic accumulation in the human body affects the lungs, kidneys, bladder, and liver and also causes various cancers. 11,12 Similarly, exposure to hypochlorite ions leads to damage of red blood cells, neuron degeneration, and lung injury. [13][14][15][16] Further, As 3+ /ClO À ions cause a severe health risk of cardiovascular and respiratory diseases.…”

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

“…1 pM) with extraordinary responses (less than 1 s). The aptasensor also could discriminate target analytes in river water samples [ 78 ]. Moreover, AuNPs-based colorimetric aptasensor using cationic polymers was performed for the detection of As 3+ in aqueous solution with the LOD of 5.3 ppb [ 82 ].…”

‘Template-free’ hierarchical MoS2foam as a sustainable ‘green’ scavenger of heavy metals and bacteria in point of use water purification

“…28,33 The scope of this material towards heavy metal studies is limited to highly sensitive biosensors for selective detection of As(III) in groundwater at a low limit of detection. 34 Conjugated MoS 2 composites have been employed to fabricate biosensors utilizing the specic properties of the different constituents of the composite for selective sensing of these toxic metal ions. 35,36 Recently, exfoliated MoS 2 nanosheets have been shown to rapidly interact with the Pb(II) and Pb(IV) species in water and yield a PbMoO 4Àx S x product.…”