3D Flower-Like MoS ₂ Nanomaterial as Signal-Promoter of PTC-PEI/S ₂ O ₈ ²⁻ System for Fabricating a Sensitive Electrochemiluminescence Methotrexate Sensor

Abstract

In this work, a sensitive polyethylenimine functionalized Perylene derivative PTC-PEI, S 2 O 8 2− and 3D flower-like MoS 2 (3D MoS 2 NFs) ternary system was fabricated for quantitation of Methotrexate (MTX) based on the quenched electrochemiluminescence (ECL) signals. Specifically, the PTC-PEI was prepared via cross-linking Perylenetetracarboxylic acid (PTCA) and polyethylenimine (PEI). Then, the hybrid nanocomposite PTC-PEI-MoS 2 was synthysized through electrostatic absorption effect between PTC-PEI and 3D MoS 2 NFs. With the excellent catalytic effect of 3D MoS 2 NFs towards the electrochemical reduction process of S 2 O 8 2− thus resulting in generation of more sulfate radical anions (SO 4 ·− ), the ECL signal probe PTC-PEI-MoS 2 exhibits higher luminous efficiency compared with PTC-PEI (3-fold enhancement). In addition, electrochemical regenerable property of Mo 6+ /Mo 4+ active sites endows 3D MoS 2 NFs excellent signal enhancement efficiency. Under the optimum conditions, a linear range from 10 μ M to 1pM with the limit of detection down to 0.15 pM could be obtained in MTX determination. Notably, the proposed strategy provides a new idea for sensitive determination of MTX.