Department of Pharmaceutical Sciences, University of Florence, Florence, Italy.
J Pharm Biomed Anal. 2011 Apr 28;55(1):64-70. doi: 10.1016/j.jpba.2011.01.007. Epub 2011 Jan 19.
A reliable, accurate and reproducible method to quantify vitamin D3 (Vit. D3) in oily dietary supplements was developed after three Vit. D3 intoxications were diagnosed as reasonably resulting from a dietary administration of a cod liver oil based supplement. Liquid chromatography coupled to mass spectrometry operating in atmospheric pressure chemical ionization conditions (LC-APCI) and by using a deuterium labelled internal standard resulted to be an effective technique to reach the analytical aim. Due to the complexity of the oily matrix, the new analytical approach required a solid phase extraction step prior to analysis. The amount of Vit. D3 declared on the label of the cod liver oil based supplement for each soft capsule is 1.5μg. Consequently, the method was developed to quantify Vit. D3 amounts in the range 1-5μg/mL. To improve reliability of obtained data, both MS and MS/MS acquisition methods were employed. The method was evaluated by measuring the characteristic parameters such as linearity, precision, accuracy and robustness and cross checked against a certified pharmaceutical preparation. The LC-APCI-MS and MS/MS methods were applied in order to assess the Vit. D3 content in the dietary supplements taken by the intoxicated patients, found about three order of magnitude higher than that declared. The Vit. D3 content of other batches of the same commercial product was found as declared.
开发了一种可靠、准确且可重现的方法，用于定量分析油性膳食补充剂中的维生素 D3（Vit. D3）。这是因为在诊断出三例因服用鱼肝油为基础的补充剂而导致合理中毒的案例后。液相色谱-大气压化学电离（LC-APCI）条件下的质谱联用，并使用氘标记的内标，是实现分析目标的有效技术。由于油基质的复杂性，新的分析方法在分析前需要进行固相萃取步骤。鱼肝油为基础的补充剂每粒软胶囊上标注的 Vit. D3 含量为 1.5μg。因此，该方法的开发旨在定量分析 1-5μg/mL 范围内的 Vit. D3 含量。为了提高数据的可靠性，同时采用了 MS 和 MS/MS 采集方法。通过测量线性度、精密度、准确度和稳健性等特征参数对方法进行了评估，并与认证的药物制剂进行了交叉检查。为了评估中毒患者所服用的膳食补充剂中的 Vit. D3 含量，应用了 LC-APCI-MS 和 MS/MS 方法，发现其含量比标注值高出约三个数量级。其他批次的同一商业产品的 Vit. D3 含量与标注值相符。
