Key Laboratory of Food Nutrition and Safety, Ministry of Education of China, Tianjin Univ. of Science and Technology, Tianjin 300457, China.
J Food Sci. 2009 Oct;74(8):T67-74. doi: 10.1111/j.1750-3841.2009.01311.x.
17beta-19-nortestosterone (17beta-NT) has been illegally used in antifatigue functional foods to promote muscle growth and improve endurance. A rapid and sensitive solid-phase extraction-enzyme-linked immunosorbent assay (SPE-ELISA) method was developed and successfully applied to analyze the levels of 17beta-NT in antifatigue functional foods. A polyclonal antibody against 17beta-NT was produced from rabbits immunized with the 17beta-NT-BSA conjugate, and a competitive direct enzyme-linked immunosorbent assay was developed for the rapid detection of 17beta-NT. The concentration causing 50% inhibition (IC(50)) and the limit of detection (LOD) were found to be 0.08 and 0.0055 ng/mL, respectively; this was better than methods previously reported that had a LOD of 2.4 ng/mL. C(18) cartridges were investigated for use in removing the effects of matrix in foods, and the sample purification protocol was optimized. Using the developed SPE-ELISA method, recoveries of functional food samples were obtained in the range of 71% to 91.5%. Moreover, 2 kinds of antifatigue functional foods were analyzed using the established ELISA and HPLC methods. The correlation coefficient of the results obtained using the 2 methods was greater than 0.98. Thus, the preliminary evaluation of the SPE-ELISA method proved that it is a specific, sensitive, and precise tool that can be used for the practical detection of 17beta-NT in various antifatigue functional food samples.
17β-19-去甲睾酮（17β-NT）曾被非法用于抗疲劳功能食品中，以促进肌肉生长和提高耐力。本研究建立了一种快速、灵敏的固相萃取-酶联免疫吸附法（SPE-ELISA），并成功应用于分析抗疲劳功能食品中 17β-NT 的含量。用 17β-NT-BSA 偶联物免疫兔子制备了针对 17β-NT 的多克隆抗体，并建立了用于快速检测 17β-NT 的竞争直接酶联免疫吸附法。结果表明，该方法的半数抑制浓度（IC50）和检测限（LOD）分别为 0.08ng/mL 和 0.0055ng/mL，优于先前报道的 LOD 为 2.4ng/mL 的方法。研究了 C18 小柱对食品中基质的去除效果，并优化了样品净化方案。采用建立的 SPE-ELISA 方法，从功能食品样品中获得的回收率在 71%至 91.5%范围内。此外，还使用建立的 ELISA 和 HPLC 方法分析了 2 种抗疲劳功能食品。两种方法所得结果的相关系数大于 0.98。因此，SPE-ELISA 方法的初步评价表明，该方法是一种特异性、灵敏性和精确性高的工具，可用于实际检测各种抗疲劳功能食品样品中的 17β-NT。
