Simultaneous determination of multiple neurochemicals in mouse brain tissue by liquid chromatography-tandem mass...

Neurochemicals play critical roles in modulating neuronal communication and brain functions, with their dysregulation resulting in neuropsychiatric disorders. The accurate quantification of these signaling molecules is essential for understanding disease mechanisms and developing therapeutics. To address the numerous drawbacks of current neurochemical analysis techniques, we herein developed and validated a liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of 55 neurochemicals in biological samples. This method employs protein precipitation and a fluorophenyl column for chromatographic separation and does not require derivatization. The mobile phase, organic solvent, and column oven temperature were optimized to enhance sensitivity and selectivity. The validated method exhibited an excellent linearity (r² > 0.990), limits of detection ranging from 0.15 to 75 ng/mL, limits of quantitation ranging from 0.5 to 250 ng/mL, and AOAC guideline-compliant intra- and interday precisions and accuracies. Using this method, we achieved separation within 13 min and quantified 45 neurochemicals in different mouse brain regions, revealing region-specific distributions. The developed approach holds promise for neuroscience research, clinical diagnostics, and the development of drug for neuropsychiatric disorder treatment.