Laboratory of Pharmaceutical Analysis, Department of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Laboratory of Pharmaceutical Technology, Department of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Molecules. 2023 Oct 14;28(20):7086. doi: 10.3390/molecules28207086.
Homotaurine (HOM) is considered a promising drug for the treatment of Alzheimer's and other neurodegenerative diseases. In the present work, a new high-performance liquid chromatography with fluorescence detection (HPLC-FLD) (λex. = 340 nm and λem. = 455 nm) method was developed and validated for the study of substance permeability in the central nervous system (CNS). Analysis was performed on a RP-C18 column with a binary gradient elution system consisting of methanol-potassium phosphate buffer solution (pH = 7.0, 0.02 M) as mobile phase. Samples of homotaurine and histidine (internal standard) were initially derivatized with ortho-phthalaldehyde (OPA) (0.01 M), N-acetylcysteine (0.01 M) and borate buffer (pH = 10.5; 0.05 M). To ensure the stability and efficiency of the reaction, the presence of different nucleophilic reagents, namely (a) 2-mercaptoethanol (2-ME), (b) N-acetylcysteine (NAC), (c) tiopronin (Thiola), (d) 3-mercaptopropionic acid (3-MPA) and (e) captopril, was investigated. The method was validated (R = 0.9999, intra-day repeatability %RSD < 3.22%, inter-day precision %RSD = 1.83%, limits of detection 5.75 ng/mL and limits of quantification 17.43 ng/mL, recovery of five different concentrations 99.75-101.58%) and successfully applied to investigate the in vitro permeability of homotaurine using Franz diffusion cells. The apparent permeability (P) of HOM was compared with that of memantine, which is considered a potential therapeutic drug for various CNSs. Our study demonstrates that homotaurine exhibits superior permeability through the simulated blood-brain barrier compared to memantine, offering promising insights for enhanced drug delivery strategies targeting neurological conditions.
高丝氨酸（HOM）被认为是治疗阿尔茨海默病和其他神经退行性疾病的有前途的药物。在本工作中，开发并验证了一种新的高效液相色谱法与荧光检测（HPLC-FLD）（λex。= 340nm 和 λem。= 455nm）方法，用于研究中枢神经系统（CNS）中的物质通透性。分析在 RP-C18 柱上进行，采用甲醇-磷酸钾缓冲液（pH = 7.0，0.02 M）作为流动相的二元梯度洗脱系统。高丝氨酸和组氨酸（内标）的样品最初用邻苯二醛（OPA）（0.01 M）、N-乙酰半胱氨酸（0.01 M）和硼酸盐缓冲液（pH = 10.5；0.05 M）衍生化。为了确保反应的稳定性和效率，研究了不同亲核试剂的存在，即（a）2-巯基乙醇（2-ME），（b）N-乙酰半胱氨酸（NAC），（c）硫普罗宁（Tiola），（d）3-巯基丙酸（3-MPA）和（e）卡托普利。该方法经过验证（R = 0.9999，日内重复性%RSD < 3.22%，日间精密度%RSD = 1.83%，检测限 5.75ng/mL 和定量限 17.43ng/mL，五个不同浓度的回收率 99.75-101.58%），并成功应用于使用 Franz 扩散池研究高丝氨酸的体外通透性。将 HOM 的表观渗透性（P）与被认为是各种 CNS 潜在治疗药物的美金刚进行了比较。我们的研究表明，与美金刚相比，高丝氨酸通过模拟血脑屏障具有更高的通透性，为针对神经疾病的增强药物输送策略提供了有前景的见解。
