Optimization of o‐phtaldialdehyde/2‐mercaptoethanol postcolumn reaction for the hydrophilic interaction liquid chromatography determination of memantine utilizing a silica hydride stationary phase

A rapid procedure for the determination of memantine based on hydrophilic interaction chromatography with fluorescence detection was developed. Fluorescence detection after postcolumn derivatization with o‐phtaldialdehyde/2‐mercaptoethanol was performed at excitation and emission wavelengths of 345 and 450 nm, respectively. The postcolumn reaction conditions such as reaction temperature, derivatization reagent flow rate, and reagents concentration were studied due to steric hindrance of amino group of memantine. The derivatization reaction was applied for the hydrophilic interaction liquid chromatography method which was based on Cogent Silica‐C stationary phase with a mobile phase consisting of a mixture of 10 mmol/L citric acid and 10 mmol/L o‐phosphoric acid (pH 6.0) with acetonitrile using an isocratic composition of 2:8 v/v. The benefit of the reported approach consists in a simple sample pretreatment and a quick and sensitive hydrophilic interaction chromatography method. The developed method was validated in terms of linearity, accuracy, precision, and selectivity according to the International Conference on Harmonisation guidelines. The developed method was successfully applied for the analysis of commercial memantine tablets.     

High-performance liquid chromatographic determination of memantine hydrochloride in rat plasma using sensitive fluorometric derivatization

In this study, we investigated a simple, sensitive and reliable liquid chromatography‐fluorescence detection method for the determination of memantine hydrochloride in rat plasma which was based on derivatization with 9‐fluorenylmethyl chloroformate (FMOC‐Cl). For the first time, FMOC‐Cl was introduced into derivatization of memantine hydrochloride in rat plasma. The amino groups of memantine hydrochloride and amantadine hydrochloride (internal standard) were trapped with FMOC‐Cl to form memantine hydrochloride‐FMOC‐Cl and amantadine hydrochloride‐FMOC‐Cl compositions, which can be very compatible for LC‐FLD. Precipitation of plasma proteins by acetonitrile was followed by vortex mixing and centrifugation. Chromatographic separation was performed on a C₁₈ column (DIAMONSIL 150×4.6 mm, id 5 μm) with a mobile phase consisting of acetonitrile and water at a flow rate of 1.0 mL/min. The retention times of memantine hydrochloride‐FMOC‐Cl and amantadine hydrochloride‐FMOC‐Cl compositions were 23.69 and 40.27 min, respectively. Optimal conditions for the derivatization of memantine hydrochloride were also described. The limit of quantification (LOQ) was 25 ng/mL for memantine hydrochloride in plasma, the linear range was 0.025–5.0 μg/mL in plasma with a correlation coefficient (r) of 0.9999. The relative standard deviations (RSDs) of intra‐day and inter‐day assays were 4.46–12.19 and 5.23–11.50%, respectively. The validated method was successfully applied to the determination of memantine hydrochloride in rat plasma samples.     

盐酸美金刚联合盐酸多奈哌齐对中重度阿尔茨海默病患者精神行为症状的疗效观察

目的评价盐酸美金刚联合盐酸多奈哌齐对阿尔茨海默病(AD)伴发精神行为症状(BPSD)的疗效及安全性.方法将符合标准的80例AD患者随机分为研究组和对照组,每组40例,治疗组患者服用盐酸美金刚和盐酸多奈哌齐,对照组患者单用盐酸多奈哌齐.盐酸美金刚起始剂量为5mg/d,每周递增5 mg ,4周末增至20mg/d;盐酸多奈哌齐起始剂量为5mg/d,4周末增至10mg/d;观察12周.治疗前及治疗12周末,分别采用痴呆行为量表(BEHAVE-AD)评价精神行为症状、日常生活能力量表(ADL)判定患者日常生活活动能力、临床总体印象量表(CGI)评定患者总体变化情况.结果治疗12周末,研究组BEHAVE-AD减分较对照组更显著(8.1±3.30,9.2±2.80,t=-3.317,P<0.01), ADL减分更显著(28.1±2.35,29.3±2.63,t=2.097,P<0.05),CGI评分分别为(3.43±0.82和4.37±0.85),差异有统计学意义(t=-5.413,P<0.01).结论盐酸美金刚联合盐酸多奈哌齐治疗BPSD的疗效优于单用盐酸多奈哌齐.     

A new HPLC method with fluorescence detection for the determination of memantine in human plasma

A sensitive, selective, simple and fast HPLC method based on the formation of derivative with fluorescamine was developed for the determination of memantine (ME) in human plasma. Separation was achieved on a CN column (200 mm×4.6 mm) using acetonitrile-10 mM orthophosphoric acid containing 1 mL/L triethylamine (45:55, v/v) at a flow rate of 1 mL/min. Emission and excitation wavelengths were 480 and 380 nm, respectively. Amantadine was used as an internal standard. Calibration graphs were rectilinear over the range of 1.0-100.0 ng/mL. Limit of detection and limit of quantification were found to be 0.3 and 1.0 ng/mL, respectively. Intra-day and inter-day relative standard deviation values were found to be <2.03%. Average recovery was also found to be around 94%. Proposed method was applied for the pharmacokinetic study in a healthy volunteer after a single oral administration of 20 mg of ME.     

盐酸美金刚胺含量分析方法的研究

在一定 p H值下 ,铵离子和二价铜离子反应 ,生成络合物在紫外有最大吸收 ,吸收波长为 36 5 nm,建立一种简便可靠的盐酸美金刚胺分析方法。盐酸美金刚胺在 1 0 0— 5 0 0 μg· m L-1范围内呈良好的线性关系 ,回归方程为 A=0 .0 0 2 6 C(r=0 .9987)。平均回收率为 1 0 0 .7%(n=6 ) ,相对标准偏差为 1 .37%。本方法简便、可靠、准确。