Introduction: The alkyl esters of p-hydroxybenzoic acid at the C-4 position, “the parabens,” including methyl, ethyl, propyl, and butyl, are widely used as antimicrobial preservatives in foods, cosmetics, and pharmaceuticals. Official regulations on the use of these compounds make their analysis essential for the estimation of their exposure.

Methods: On this basis, the presented study was realized to develop a simple, selective and cheap high-performance liquid chromatographic method for the quantitative determination of methylparaben, ethylparaben (EP), n-propyl paraben (NPP), isopropyl paraben (IPP), n-butyl paraben (NBP), isobutyl paraben (IBP) and benzyl paraben (BP) in pharmaceuticals and cosmetic products.

Results: The chromatographic separation of the analytes was achieved under flow rate gradient elution conditions using a C18-bonded core-shell silica particle column (2.6 μm particle size, 150 × 3.0 mm from Phenomenex Co.). The samples were injected into the system as aliquots of 1.0 μL, and the compounds were detected by using a photodiode array detector set at 254 nm wavelength. With this technique, seven paraben derivatives can be determined in the concentration range of 250-2000 ng/mL. The recovery of the method is in the range of 99.95-13.84%, and the RSD is at a maximum value of 3.95%.

Conclusion: The proposed method was fully validated and successfully applied to different pharmaceutical and cosmetic samples (n=16), including syrups, suspensions, oral sprays, gels, etc. At least one paraben derivative was detected in six samples and was determined quantitatively. The maximum amount of a paraben derivative found in the analyzed samples was 321.7 ng/mL, which was MP. To the best of our knowledge, this is the first LC method, which is applicable both on pharmaceutical and cosmetic samples.

简介： C-4 位对羟基苯甲酸的烷基酯，“对羟基苯甲酸酯”，包括甲基、乙基、丙基和丁基，广泛用作食品、化妆品和药物中的抗菌防腐剂。关于使用这些化合物的官方规定使其分析对于估计其暴露量至关重要。

方法：在此基础上，实现本研究开发一种简单、选择性和廉价的高效液相色谱方法，用于定量测定对羟基苯甲酸甲酯、对羟基苯甲酸乙酯（EP）、对羟基苯甲酸正丙酯（NPP）、对羟基苯甲酸异丙酯（IPP） 、对羟基苯甲酸正丁酯 (NBP)、对羟基苯甲酸异丁酯 (IBP) 和对羟基苯甲酸苄酯 (BP) 在药品和化妆品中的应用。

结果：分析物的色谱分离是在流速梯度洗脱条件下使用 C18 键合核壳硅胶颗粒柱（2.6 μm 粒径，150 × 3.0 mm，来自 Phenomenex Co.）实现的。将样品以 1.0 μL 的等分试样注入系统，并使用设置为 254 nm 波长的光电二极管阵列检测器检测化合物。使用这种技术，可以测定 250-2000 ng/mL 浓度范围内的七种对羟基苯甲酸酯衍生物。该方法的回收率为99.95-13.84%，RSD最大值为3.95%。

结论：所提出的方法经过充分验证并成功应用于不同的药物和化妆品样品（n=16），包括糖浆剂、混悬剂、口腔喷雾剂、凝胶剂等。在六个样品中至少检测到一种对羟基苯甲酸酯衍生物并进行了定量测定。在分析样品中发现的对羟基苯甲酸酯衍生物的最大量为 321.7 ng/mL，即 MP。据我们所知，这是第一种同时适用于药物和化妆品样品的液相色谱方法。