College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801, PR China.
College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi 030801, PR China.
Food Chem. 2024 May 30;441:138377. doi: 10.1016/j.foodchem.2024.138377. Epub 2024 Jan 9.
Immunomagnetic beads provide novel tools for high-throughput immunoassay techniques. In this study, protein G (PG) was immobilized onto bacterial magentic particles (BMPs) using an additional cysteine residue at the C-terminus. A broad-spectrum monoclonal antibody against glucocorticoids (GCs) was attached to BMPs through PG-Fc interaction, generating BMP-PG-mIgG immunomagentic beads. A sensitive one-step immunoassay was developed for GCs based on combination of BMP-PG-mIgG and dexamethasone-horseradish peroxidase tracer (DMS-HRP). The developed assay exhibited half inhibitory concentrations (IC) for dexamethasone (DMS), betamethasone (BMS), prednisolone (PNS), hydrocortisone (HCS), beclomethasone (BCMS), cortisone (CS), 6-α-methylprednisone (6-α-MPNS), fludrocortisone acetate (HFCS) of 0.98, 1.49, 2.42, 9.29, 1.63, 6.13, 7.3, and 4.89 ng/mL, respectively. The method showed recoveries ranging rates from 86.5 % to 117 % with a coefficient of variation less than 12.3 % in milk sample, which showed a good correlation with LC-MS/MS. Thus, the proposed assay offers a rapid and broad-spectrum screening tool for simultaneous detection of GCs in milk.
免疫磁珠为高通量免疫分析技术提供了新颖的工具。在这项研究中，通过在 C 末端添加额外的半胱氨酸残基，将蛋白 G（PG）固定在细菌磁珠（BMP）上。将一种针对糖皮质激素（GCs）的广谱单克隆抗体通过 PG-Fc 相互作用连接到 BMP 上，生成 BMP-PG-mIgG 免疫磁珠。基于 BMP-PG-mIgG 和地塞米松辣根过氧化物酶示踪剂（DMS-HRP）的组合，开发了一种用于 GCs 的灵敏一步法免疫测定法。开发的测定法对半抑制浓度（IC）为地塞米松（DMS）、倍他米松（BMS）、泼尼松龙（PNS）、氢化可的松（HCS）、倍氯米松（BCMS）、可的松（CS）、6-α-甲基泼尼松龙（6-α-MPNS）、醋酸氟氢可的松（HFCS）分别为 0.98、1.49、2.42、9.29、1.63、6.13、7.3 和 4.89 ng/mL。该方法在牛奶样品中的回收率范围为 86.5%至 117%，变异系数小于 12.3%，与 LC-MS/MS 具有良好的相关性。因此，该方法提供了一种快速、广谱的筛选工具，可用于同时检测牛奶中的 GCs。
