U.S. Food and Drug Administration, Center for Veterinary Medicine, Office of Applied Science, 8401 Muirkirk Rd, Laurel, MD 20708, USA.
J AOAC Int. 2023 May 3;106(3):517-522. doi: 10.1093/jaoacint/qsad032.
Antibiotics are used in ethanol production to discourage undesirable bacteria growth. To determine if antibiotic residues remain in the distillers grain (DG) byproduct, which is used as an animal food ingredient, the U.S. Food and Drug Administration/Center for Veterinary Medicine previously developed an LC-MS/MS method to detect residues of erythromycin A, penicillin G, virginiamycin M1, and virginiamycin S1 in DG to enable regulatory decision-making.
Erythromycin and penicillin G were quantitated using the stable isotope dilution technique with their isotopically labeled compounds, which are considered optimal internal standards (ISTDs) for quantitative mass spectrometry. With the commercial availability of virginiamycin M1-d2 since then, the objectives of this study were to evaluate the feasibility of its use as it is only doubly deuterated, and to incorporate it in the method to enhance method performance.
Antibiotic residues were solvent-extracted from DG; the extract was cleaned up by a hexane wash and solid phase extraction (SPE) and analyzed by LC-MS/MS.
We established suitability of virginiamycin M1-d2 as an ISTD and incorporated it in the method. For all analytes, accuracy and precision ranged 90 to 102% and 3.8 to 6.8, respectively.
We modified a previously developed LC-MS/MS method that uses virginiamycin M1-d2 as an ISTD to support surveillance studies to determine several drugs in DG.
Virginiamycin M1-d2 was successfully incorporated into the method for better virginiamycin M1 quantitation. This addition also allowed calibration curves for all analytes to be constructed in solvent, thereby simplifying the method.
抗生素被用于乙醇生产中，以抑制不良细菌的生长。为了确定用作动物饲料成分的酒糟副产品中是否残留抗生素，美国食品和药物管理局/兽医中心先前开发了一种 LC-MS/MS 方法来检测酒糟中红霉素 A、青霉素 G、维吉尼亚霉素 M1 和维吉尼亚霉素 S1 的残留，以做出监管决策。
使用稳定同位素稀释技术及其同位素标记化合物对红霉素和青霉素 G 进行定量，这些化合物被认为是定量质谱分析的最佳内标 (ISTD)。自那时以来，维吉尼亚霉素 M1-d2 已商业化，本研究的目的是评估其作为仅双氘代化合物的使用可行性，并将其纳入方法中以提高方法性能。
抗生素残留从酒糟中溶剂萃取；提取物用正己烷洗涤和固相萃取 (SPE) 进行净化，并通过 LC-MS/MS 进行分析。
我们确定了维吉尼亚霉素 M1-d2 作为 ISTD 的适用性，并将其纳入方法中。对于所有分析物，准确度和精密度分别在 90%至 102%和 3.8%至 6.8%之间。
我们修改了先前开发的 LC-MS/MS 方法，该方法使用维吉尼亚霉素 M1-d2 作为 ISTD 来支持监测研究，以确定酒糟中的几种药物。
成功将维吉尼亚霉素 M1-d2 纳入方法，以更好地定量维吉尼亚霉素 M1。此添加还允许在溶剂中构建所有分析物的校准曲线，从而简化了方法。
