AA3型连续流动分析仪与钒钼黄比色法测定玉米植株全磷含量之比较

摘要

The vanadium molybdate yellow colorimetric method(VMYC method)is regarded as one of conventional methods for determining total phosphorus(P)in plants, but it is time consuming procedure. Continuous flow analyzer(CFA)is a fluid stream segmentation technique with air segments. It is used to measure P concentration based on the molybdate-antimony-ascorbic acid method of Murphy and Riley. Sixty nine of maize plant samples were selected and digested with H2SO4-H2O2. P concentrations in the digests were determined by CFA and VMYC method, respectively. The t test found that there was no any significant difference of the plant P contents measured by the CFA and the VMYC method. A linear equation could best describe their relationship:Y(CFA-P)=0.927X(VMYC-P)-0.002. The Pearson’s correlation coefficient was 0.985 with a significance level(n=69, P<0.01). The CFA method for plant P measurement had a high precision with relative standard deviation(RSD)less than 1.5%. It is suggested that the CFA based on Murphy and Riley colorimetric detection can be used to determinate total plant P in the digests solutions with H2SO4-H2O2. The CFA method is labor saving and can handle large numbers of samples. The human error in mixing with other operations is reduced to a great extent.%选择69个玉米秸秆和籽粒样品，经浓H2SO4和H2O2消煮后，用连续流动分析仪与钒钼黄比色法分别测定消煮液中磷含量，对2种方法检测数据之间进行比较分析，探讨利用连续流动分析仪测定植株样品消煮液中磷含量的可行性。t检验表明：2种方法测定植株全磷含量相比无明显差异。测定结果之间呈显著线性相关系，回归直线方程为Y（连续流动分析仪-P）=0.927X（钒钼黄比色法-P）-0.002，相关系数r=0.985（n=69，P<0.01）。连续流动分析仪测定加标回收率在99.3%~103.8%之间，对4个样品消煮液中磷浓度分别重复测定10次，相对标准偏差小于1.5%。连续流动分析仪分析速度快，消耗试剂少，推荐用于大批量玉米植株样品H2SO4-H2O2消煮液中磷含量分析。