Study on the pharmacokinetics and distribution of exogenous taurine in a brain by ¹⁴C-nanotracing technique based on accelerator mass spectrometry

When developing new drugs for brain diseases, assessing the distribution of these compounds within the brain is essential for establishing their therapeutic effectiveness. Taurine has recently shown promising effects in improving cognitive deficits, particularly for patients with Alzheimer's disease (AD). The conventional method for measuring drug concentrations liquid chromatography-tandem mass spectrometry (LC-MS/MS) is often limited when quantifying exogenous taurine specifically in targeted brain regions. This limitation arises because endogenous taurine is already present at high concentrations in plasma and the central nervous system (CNS), making it challenging to distinguish between endogenous and externally administered taurine. In this study, we used a novel approach to address this issue. After administering a therapeutic dose of taurine, along with a trace amount of ¹⁴C taurine to mice, we employed accelerator mass spectrometry (AMS) to accurately measure minute concentrations (ng/mg) of exogenous taurine in milligram-sized brain tissue samples. This method effectively reduced interference from endogenous taurine, enabling precise quantification of the administered taurine. Our findings highlight the importance of AMS as a sensitive tool for more accurately assessing drug distribution in the brain.