高效液相色谱法和分光光度法测定水溶肥料中壳聚糖含量的方法比较

Comparison of HPLC and spectrophotometry for the determination of chitosan in water-soluble fertilizers

建立了高效液相色谱法和分光光度法测定水溶肥料中壳聚糖含量的不同分析方法,对壳聚糖的水解条件进行了系统的考究。结果表明,以1+1的盐酸溶液,温度100℃,时间24 h水解效果最佳。以1-苯基-3-甲基-5-吡唑啉酮(PMP)作为衍生剂的高效液相色谱法的线性范围、检出限和加标回收率分别为1~200 mg/L、0.07 mg/L和95%~101%,分光光度法相应的指标分别为0~100μg、0.47μg和94%。经比较,这2种方法对水溶肥料样品的测定结果一致性较好,均能满足水溶肥料中壳聚糖含量的分析要求。其中,高效液相色谱法干扰因素更少,效率更高。此外,也尝试采用氯甲酸芴甲酯(FMOC-Cl)作为衍生剂对壳聚糖水解产物进行衍生,然后用高效液相色谱法进行检测,发现所测结果也与上述2种方法基本相符,但本研究所建立的高效液相色谱法和分光光度法不适用于含硝酸根的水溶肥料壳聚糖含量的测定。

Different analytical methods for the determination of chitosan in water-soluble fertilizers by high performance liquid chromatography and spectrophotometry were established.The hydrolysis conditions of chitosan were systematically investigated,and the test results showed that chitosan could be quantitatively hydrolyzed into glucosamine in 24 h with hydrochloric acid(1+1)at 100℃.The linearity range,limit of detection and recovery rate of high performance liquid chromatograply with 1-phenyl-3-methyl-5-pyrazolone(PMP)as the derivatizing agent were 1~200 mg/L,0.07 mg/L and 95%~101%,respectively.For spectrophotometry,they were 0~100μg,0.47μg and 94%,respectively.By comparison,the results of the two methods for the determination of water-soluble fertilizers were consistent,and both methods could meet the requirements for the analysis of the chitosan content in water-soluble fertilizers,and high performance liquid chormatography had less interference factors and higher efficiency.In addition,9-fluorenylmethoxycarbonyl chloride was used as another derivatizing agent,and the results were basically consistent with the two methods mentioned above.However,the methods of high performance liquid chormatography and spectrophotometry established in this study are not suitable for the determination of chitosan in water-soluble fertilizers containing nitrate nitrogen.