微波萃取高效液相色谱法测定塑料及其制品中荧光增白剂

采用微波萃取高效液相色谱法对塑料及其制品中5种荧光增白剂含量进行测定。将样品冷冻粉碎,过0.84mm的分样筛,用25 m L三氯甲烷–丙酮(3∶2)为萃取剂,在90℃的条件下微波萃取10 min,用高效液相色谱进行定性定量分析。采用Acclaim Phenyl-1柱(150 mm×4.6 mm,3μm)为分析柱,以甲醇–水(95∶5)为流动相,荧光检测器激发波长为365 nm,发射波长为430 nm。2,5-双(5-叔丁基-2-苯并恶唑基)噻吩(OB)、1,4-双(苯并恶唑基-2-基)萘(KCB)、4,4'-双(2-苯并恶唑基)二苯乙烯(OB–1)、4-(2-苯并恶唑基)-4'-(5-甲基-2-苯并恶唑基)二苯乙烯(KSN)和4,4'-双(2-甲氧基苯乙烯基)联苯(FP–127)5种荧光增白剂的质量浓度在0.5~150μg/L范围内与色谱峰面积呈良好线性关系,相关系数r≥0.999 7,检出限为0.013~0.025 mg/kg,加标回收率为84.7%~104.7%,测定结果的相对标准偏差为1.5%~4.4%(n=6)。该方法简便、准确、灵敏度高,适用于塑料及其制品中荧光增白剂含量的测定。

Determination of Fluorescent Whitening Agents in Plastics and Plastic Articles by Microwave Extraction High Performance Liquid Chromatography

A method was used for the determination of 5 kinds of fluorescent whitening agents in plastics and plastic articles by microwave extraction high performance liquid chromatography(HPLC).The samples were frozen and crushed,sifted by 0.84 mm aperture sieve,and microwave extracted with 25 mL trichloromethane-acetone(3:2) for 10 min at 90℃,the HPLC method was performed on qualitative and quantitative analysis.Acclaim Phenyl-1 column(150 mm × 4.6 mm,3 μm) was used with methanol-water (95:5) as the mobile phases,the excitation wavelength was 365 nm and the emission wavelength was 430 nm.The results showed that the eoncentration of 5 kinds of fluorescent whitening agents such as 2,5-bis(5-tert-butyl-2-benzoxazolyl)thiophene (OB),1,4-bis(2-benzoxazolyl)-naphthalene(KCB),4,4'-bis(2-benzoxazolyl)stilbene(OB-1),4-(2-benzoxazolyl)-4'-(5-methyl-2-benzoxazolyl) stilbene(KSN) and 4,4'-bis(2-methoxystyryl) biphenyl(FP-127) was linear with the chromatography peak area in the range of 0.5-150 μ g/L,the correlation coefficients were not less than 0.999 7,the detection limits were 0.013-0.025 mg/kg,the recoveries were 84.7％-104.7％,and the relative standard deviation of detection results was 1.5％-4.4％(n=6).The method is simple,accurate and sensitive,so it is suitable for the determination of the fluorescent whitening agents in plastics and plastic articles.