Li Xiangmei, Chen Xiaomin, Wu Jinxiao, Liu Zhiwei, Wang Jin, Song Cuiping, Zhao Sijun, Lei Hongtao, Sun Yuanming
Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou 510642, China.
Shanxi Institute of Feed and Veterinary Drug control, No. 5 Shengli West Street, Jiancaoping District, Taiyuan 030000, China.
Foods. 2021 Jun 10;10(6):1339. doi: 10.3390/foods10061339.
Dexamethasone (DEX) is widely used because of its anti-inflammatory, anti-endotoxin, anti-shock, and stress-enhancing response activities. It can increase the risk of diabetes and hypertension if it is abused or used improperly. However, there is a lack of sensitive and rapid screening methods for DEX in food. In this study, a time-resolved fluorescent microspheres immunochromatographic assay (TRFM-ICA) integrated with a portable fluorescence reader was developed for the quantitative detection of DEX in milk and pork. The cut-off values of the TRFM-ICA were 0.25 ng/mL and 0.7 µg/kg, respectively. The limits of quantitation (LOQs) were 0.003 ng/mL and 0.062 µg/kg, respectively. The recovery rates were 80.0-106.7%, and 78.6-83.6%, respectively, with the coefficients of variation ranging 6.3-12.5%, and 7.5-10.3%, respectively. A parallel experiment for 20 milk and 10 pork samples with LC-MS/MS was carried out to confirm the performance of the on-site application of the developed TRFM-ICA. The results of the two methods are basically the same; the correlation (R) was >0.98. The establishment of TRFM-ICA will provide a new sensitive and efficient technical support for the rapid screening of DEX in food.
地塞米松（DEX）因其抗炎、抗内毒素、抗休克及增强应激反应活性而被广泛应用。若滥用或使用不当，它会增加患糖尿病和高血压的风险。然而，食品中缺乏灵敏快速的地塞米松筛查方法。本研究开发了一种结合便携式荧光读数器的时间分辨荧光微球免疫层析测定法（TRFM-ICA），用于定量检测牛奶和猪肉中的地塞米松。TRFM-ICA的截断值分别为0.25 ng/mL和0.7 μg/kg。定量限（LOQ）分别为0.003 ng/mL和0.062 μg/kg。回收率分别为80.0 - 106.7%和78.6 - 83.6%，变异系数分别为6.3 - 12.5%和7.5 - 10.3%。对20份牛奶和10份猪肉样品进行了与液相色谱 - 串联质谱法（LC-MS/MS）的平行实验，以确认所开发的TRFM-ICA现场应用的性能。两种方法的结果基本相同；相关性（R）>0.98。TRFM-ICA的建立将为食品中地塞米松的快速筛查提供一种新的灵敏高效的技术支持。
