固相萃取-高效液相色谱法测定牙膏中过氧化苯甲酰

目的 建立固相萃取-高效液相色谱法测定牙膏中违禁添加剂过氧化苯甲酰的测定方法。方法 以Na2S2O3作为还原剂,将牙膏中的过氧化苯甲酰还原为苯甲酸,再经MAX固相萃取小柱富集净化,经XDB C18色谱柱分离。流动相为甲醇-乙酸铵缓冲液(0.02mol/L,pH=4.9)(33〖DK〗∶67,v/v),流速1.0ml/min,检测波长230nm,标准曲线法定量。结果 本法在0~100mg/L时线性相关系数 r =0.999 7,检出限为0.3mg/kg,相对标准偏差为1.8%~7.9%,回收率范围为97.6%~100.5%。结论 该法灵敏度高,准确度好,适用于牙膏中违禁添加剂过氧化苯甲酰的检测。

Determination of benzoyl peroxide in toothpaste by solid-phase extraction and high performance liquid chromatography

Objective To establish a method for determination of benzoyl peroxide in toothpaste by solid-phase extraction and high-performance liquid chromatography. Methods Benzoyl peroxide in toothpaste was reduced to benzoyl benzoic acid with a reducing agent Na2S2O3 and then purified with MAX solid-phase extraction cartridge and finally separated with an XDB C18 column.Methanol-ammonium acetate buffer(0.02mol/L,pH=4.9)(33〖DK〗∶67,v/v)was used as the mobile phase with a flow rate of 1.0ml/min and a detection wavelength of 230nm.The quantification was based on the standard curve. Results The correlation coefficient of benzoyl peroxide was 0.999 7 with a linear range of 0-100mg/L and a detection limit of 0.3mg/kg.The relative standard deviations were between 1.8% and 7.9% and the recoveries ranged from 97.6% to 100.5%. Conclusion This sensitive and accurate method is suitable for the detection of benzoyl peroxide in toothpaste.