Nanoparticle-mediated molecularly imprinted electrochemical sensor MIPs/ Au NPs/MoS 2 NPs/SPE for highly sensitive detection of γ-aminobutyric acid

A nanoparticles-modified molecularly imprinted polymers (MIPs) sensor was successfully developed for the highly sensitive recognition and detection of γ-aminobutyric acid (GABA), a crucial biomarker associated with mental disorders. Notably, the synergistic combination of molybdenum disulfide nanoparticles (MoS ₂ NPs) and gold nanoparticles (Au NPs) functioned as an efficient nanoparticle-mediated active layer, significantly enhancing the electrochemical response. Subsequently, a molecularly imprinted membrane was polymerized on this modified surface to achieve selective GABA recognition. To further improve detection performance, Prussian blue nanoparticles (PB NPs) were incorporated as a “built in” redox probe embedded into polypyrrole (PPY) framework. Additionally, a "Relative Oxidation Peak Height" analytical approach was introduced, effectively mitigating interference from various intrinsic and extrinsic factors. Under optimized conditions, the sensor demonstrated good linearity across a broad concentration range (1 nM − 100 µM), where the reduction in redox probe current intensity correlated precisely with GABA concentration. The achieved limit of detection (LOD) was 7.82 × 10 ^− 10 M (S/N = 3). Importantly, the sensor displayed minimal cross-reactivity toward common interfering neurotransmitters such as glutamic acid (Glu), serotonin (5-HT), and acetylcholine (ACh). Validation experiments using artificial cerebrospinal fluid samples yielded recovery rates ranging from 96.65% to 105.2%, with relative standard deviation (RSD) values consistently below 5%. Our results reveal that the controllable preparation of high-quality GABA MIPs electrochemical sensor, or other neurotransmitter sensor, can use this preparation and testing methods.