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Determination of 5 fluorescent whitening agents in packaging paper by high performance liquid chromatography( HPLC)

Objective A detection method is developed in this study to simultaneously detect five different kinds of 4,4'-diaminostilbene-2,2'-disulfonic acid fluorescent whitening agents( DSD-FWAs) in packaging paper by high performance liquid chromatography( HPLC). Methods Samples were ultrasonically extracted with acetonitrile / water / trimethylamine( 40∶60∶1,V / V) and then the target agents were separated on Eclipse XDB-C18 column,Methanol-acetonitrile-TBA-water( p H =8. 0) was used as the mobile phase with gradient elution. The flow rate of the mobile phase was 1. 0 ml / min,and then detected with a fluorescence detector. Results Five kinds of DSD-FWAs including C. I. 113,C. I. 71,C. I. 85,C. I. 24 and C. I. 353 can be effectively separated. There were good linearity in the concentration range of 0. 01 mg / L-20. 0 mg / L with correlation coefficients greater than 0. 999 2. The average recoveries of the five compounds ranged from 80. 2% to 93. 2% at the spiked levels of 1. 0 mg / L,5. 0 mg / L with relative standard deviations( RSD) of 2. 5%-6. 4%. Conclusion The method is simple,accurate and highly selective,and can be used for the rapid determination of the five FWAs in food packaging paper.