Water-soluble pillar[5]arene-modified graphdiyne functional material and its application towards ultrasensitive and robust electrochemical methylamphetamine determination

Abstract

Graphdiyne (GDY), which is an sp- and sp²-hybridized 2D graphene-like material, shows an abundant fully π-conjugated system and excellent conductivity. In addition, water-soluble pillar[5]arene (WP5) displays outstanding host–guest recognition properties. Therefore, the electrochemical sensing system of WP5–GDY, constructed via strong π–π stacking between WP5 and GDY, shows prominent conductivity and a supramolecular recognition ability. Hence, the ultrasensitive and robust electrochemical determination of methylamphetamine (MA) was developed using the novel composite of WP5–GDY for the first time. For MA detection, the electrochemical sensor showed a linear response range of 0.05–30.0 μM and a detection limit of 0.016 μM (S/N = 3). The host–guest mechanism between WP5 and MA was studied via binding constant (K_a) measurements, molecular docking, and ¹H NMR analysis. The developed electrochemical sensing platform was also successfully used to detect MA in human urine samples, which confirms its potential applications in the detection of drugs of abuse, illicit drugs and misused prescriptions, which will protect public health, social stability and global security.