荧光猝灭法测定壳聚糖含量

在pH 6.3的NaH2PO4-Na2HPO4缓冲溶液中,壳聚糖对荧光素的荧光强度具有明显的猝灭作用,且在一定浓度范围内,其猝灭程度与加入的壳聚糖浓度成线性关系,据此建立了一种新的测定壳聚糖含量的荧光猝灭分光光度法。该方法的回归方程为ΔF=64.02+42.28ρ(mg/L),R2=0.9942,线性范围为0.50~10.0 mg/L,检出限为0.27 mg/L。样品测定的RSD为4.5%(n=6),平均回收率为99.3%。采用该方法可测定复杂样品中的壳聚糖含量。

A fluorescence quenching method for determination of chitosan

A sensitive fluorescence quenching method was developed for the determination of chitosan based on its notable quenching effect on the fluorescence of fluorescein in a sodium phosphate buffer solution (pH 6.3). The quenched degree of fluorescence of fluorescein at a fixed concentration was in linear relationship with the added concentration of chitosan. The linear equation of the method was AF = 64.02 + 42.28,0 (mg/L) (R~2 =0.9942) with the linear range of 0.5～10.0 mg/L and the detection limit of 0.27 mg/L. The relative standard deviation was 4.5% (n=6) and the mean recovery was 99.3%. This method can be applied to the determination of chitosan in complex samples.