Attomolar analyte sensing technique for detection of Pb2+ and Hg2+ ions based on liquid crystal

Detecting the ultra-low abundance of heavy metals in real samples remains challenging and it requires the development of high-performance biosensing modalities. This work describes a novel strategy for design an ultrasensitive liquid crystal (LC) aptasensor, in which the LCs reorientation induced by conformational changes of a triple helix molecular switch (THMS) structure is utilized for the quantitative detection of Pb2+ and Hg2+ ions. The developed aptasensor exhibits a wide linear range with the ultralow detection limits as low as 0.021 aM and 0.068 aM for Pb2+ and Hg2+, respectively. Besides, the results show that other analytes cause no interference. Noteworthy, this sensing strategy is easy to expand for other targets by altering the aptamer sequence without change of the triple-helix structure and can be used for multiple analyte detection. The developed aptasensor is promising powerful platform as a LC AttoSens for precision screening of hazardous residues in food analysis.

Automated summary

This work describes a novel strategy for designing an ultrasensitive liquid crystal (LC) aptasensor, which utilizes the reorientation of LCs induced by conformational changes of a triple helix molecular switch (THMS) structure for the quantitative detection of Pb2+ and Hg2+ ions. The developed aptasensor exhibits a wide linear range with ultralow detection limits, and is not interfered by other analytes. Additionally, this sensing strategy can be easily expanded for other targets and used for multiple analyte detection, showing promising potential as a LC AttoSens for precision screening of hazardous residues in food analysis.