An electrochemical sensor based on an amino-functionalized metal–organic framework for the highly sensitive detection of glutamate

Abstract

Glutamate serves as an essential excitatory neurotransmitter in the central nervous system and participates in numerous biochemical processes in living organisms. In this research, an ultra-high sensitivity electrochemical sensor was engineered for the detection of glutamic acid. The sensing electrode was fabricated by modifying the metal–organic framework material NH₂-MIL-88B(Fe). The synthesis of NH₂-MIL-88B(Fe) metal–organic structures was achieved through a direct solvothermal method. Subsequently, a dependable differential pulse voltammetry (DPV) methodology is utilized to augment the electrochemical efficacy for Glu detection, yielding heightened sensitivity, reduced detection thresholds, an expanded linear range, and superior anti-interference properties. Under optimal conditions, the sensor displayed a linear response over a concentration range of 2 to 500 μM, achieving a lower limit of detection (LOD) as minimal as 0.92 μM, and the sensor showcased remarkable sensitivity, measuring 2630 μA mM⁻¹ cm⁻². Furthermore, even in environments containing common interfering substances, the sensor maintains commendable selectivity to Glu, thereby indicating its significant potential applications in healthcare settings.