毛细滴管数滴微型滴定法测定几种果蔬中V_C含量

以自制的液滴体积为0.01～0.02 mL的聚乙烯毛细滴管对果蔬中V_c的含量进行数滴分析,其主要仪器外形小巧、便于携带,滴定快速、准确,试剂消耗量约为常量法的1/20,滴定剂用量约为30～150滴,V_c含量不确定度U_(rel)(C)为0.56%,与常量法相当,相对标准偏差比常量法略小。该法克服了常量法中滴定管、移液管、铁架台和蝴蝶夹等仪器携带不便的不足,适用于水果、蔬菜、饮料等维生素含量的快速分析。

Determination of Vitamin C in Fruits and Vegetables by Counting Drop of Capillary Burette Micro Titration

A counting drop analysis method in determination of vitamin C in fruits and vegetables have been stud- ied by home—made polyethylene capillary burette of 0.01 to 0.02 mL/per drop,its main apparatus is small,simple, easily made and portable to carry,Consumption of reagent is about twentieth of regular—amount method,dosage of titration is only about 30 to 150 drops,the related expanded uncertainty U_(rel)(C)of vitamin C is about 0.56%,corre- spond to regular—amount method,the relative error rsd(%)is a little smaller than regular—amount method;The method overcomes the inconvenience in carrying burette,suction pipette,iron set,butterfly clip in common analysis, and is quite suitable for rapid analysis of vitamin C in fruits,vegetables and beverage.