藏红T与六偏磷酸钠的相互作用及在食品分析中的应用

The Interaction of Safranine T with Sodium Hexametaphosphate and Its Application in Food Analysis

对阳离子荧光染料藏红T(ST)在食品添加剂六偏磷酸钠(SHMP)存在时的溶液状态的荧光光谱及吸收光谱进行了研究。结果发现,在醋酸-醋酸钠缓冲条件下,SHMP使ST溶液发生自聚集,同时因静电作用二者形成杂化聚集体,导致ST的荧光强度和吸光度降低且在476 nm处出现新的吸收峰,但ST的荧光寿命没有发生明显的变化,表明SHMP静态猝灭ST的荧光。根据SHMP存在时ST吸光度的变化,建立了一种检测食品添加剂六偏磷酸钠的新方法,线性范围为1.0×10-6～1.1×10-5 mol/L,检测限为3.4×10-7 mol/L。方法成功应用于饮料中六偏磷酸钠的测定,相对标准偏差小于4.6%,回收率在95.0%～104.0%之间。

The visible spectra and fluorescent spectra of safranine T（ST） solutions with the presence of sodium hexametaphosphat（SHMP） were investigated.The results showed that ST tends to aggregate when SHMP was presented and a heteropolymer appeared by electrostatic attraction between ST and SHMP in the HAc-NaAc buffer solution,which results in a new peak appeared in 476 nm in visible absorption spectra and the intensity of the absorbance and the fluorescence decreased.Meanwhile,the fluorescent lifetime of the ST was not changed,which suggested that the fluorescence of ST is statically quenched by SHMP.Based on the change of absorbance,we have established a new method to detect the SHMP.Under optimized conditions,the linear range was 1.0×10-6~1.1×10-5 mol/L with the detection limit of 3.4×10-7 mol/L.The application of the established method in the determination of tea drink samples gave a recovery rate of 95.0%~104.0%,with a relative standard deviation of less than 4.6%.