UPLC-FLD/PDA双检测器串联测定纸质食品包装材料中11种荧光增白剂

Determination of eleven fluorescent whitening agents in paper food packaging materials by UPLC-FLD/PDA with series double-detector

目的建立一种应用超高效液相色谱仪（UPLC）-FLD/PDA双检测器串联快速测定纸质食品包装材料中11种荧光增白剂的新型检测方法。方法样品经40%乙腈水溶液提取后,采用Waters ACQUITY UPLC BEH C_（18）柱（1.7μm,2.1 mm×100 mm）分离,流动相梯度洗脱,荧光检测器（FLD）激发波长350nm,发射波长430nm,二极管阵列检测器（PDA）350 nm波长,串联荧光和二极管阵列检测器进行双检测器定性定量测定。结果在纸杯、纸碗、纸盘、纸盒4种基质中,11种荧光增白剂得到良好分离,荧光检测器与二极管阵列检测器在25-1000 ng/m L线性范围内,相关系数均大于0.99,加标回收率为82.2%-104.1%,RSD均小于10%（n=6）。11种荧光增白剂检出限：荧光检测器为0.20-0.28 mg/kg,二极管阵列检测器为1.4-2.5 mg/kg。结论 UPLC-FLD/PDA法可以分离11种荧光增白剂,且峰形较好、回收率高、易于操作,是测定纸质食品包装材料中荧光增白剂的有效方法。

Objective To establish a new qualitative and quantitative ultraperformance liquid chromatography-fluorescence detector / photodiode array detector with series double-detector method for the determination of eleven fluorescent whitening agents in paper food packaging materials. Methods The sample was extracted with 40%acetonitrile water solution,separated by Waters ACQUITY UPLC BEH C_（18）column（ 1. 7μm,2. 1 mm × 100 mm） and eluted gradient. The excitation wavelength and emission wavelength of fluorescence detector（ FLD） were 350 nm and 430 nm,and the wavelength of photodiode array detector（ PDA） was 350 nm. The detectors were used in series to achieve qualitative and quantitative detection. Results In the substrates of paper cups,paper bowls,paper trays and paper boxes,those eleven fluorescent whitening agents were separated properly. For both detectors,in the linear range of 25- 1000 ng / m L,the correlation coefficient was greater than 0. 99,and the recoveries of spiked recoveries were between 82. 2%- 104. 1% with the RSD less than 10%（ n = 6）. The detection limits ofthose eleven fluorescent whitening agents were 0. 20- 0. 28 mg / kg for FLD and 1. 4- 2. 5mg / kg for PDA. Conclusion The eleven fluorescent whitening agents could be separated properly with complete separation,good shapes and high recovery rate. This method is easy to operate also. Thus it＇s an effective method to detect the fluorescent whitening agents in paper food packaging materials.