离子选择电极法校准微量移液器方法的建立及验证

The establishment and validation of calibration method for micropipettor with ISE

目的建立离子选择电极法校准微量移液器的方法并用传统称重法验证其性能。方法配制浓度为2 000 mmol/L的氯化钾标准液,分别选用容量为10μl、50μl、100μl的3支定值移液器,将其稀释成浓度为4.00 mmol/L的氯化钾溶液,采用离子选择电极法测定稀释溶液中K+的浓度,根据实测值与标准值之间的差值校准移液器容量,用称重法验证比较。结果经离子选择电极法校准后的3支移液器测定钾离子的浓度,换算成体积分别为(10.00±0.057)μl、(50.06±0.409)μl、(100.17±0.890)μl;用称量法进行比较,其测量结果分别为(10.20±0.326)μl、(50.06±0.494)μl、(100.36±0.351)μl,2种方法比较差异无统计学意义(P>0.05)。结论采用离子选择电极法测定钾离子的浓度对微量移液器进行容量校准,与传统称重法结果一致,方法简便易行,可作为移液器容量校准的替代方法加以推广应用。

Objective To establish calibration method for micropipettor with ion selective electrode（ ISE） and verify its performance with the traditional weighing method. Methods Make up kalium chloratum standard solution with concentration of2 000 mmol / L and choose 3 fixed value micropipettors with capacity of 10 μl,50 μl,100 μl to dilute the kalium chloratum into one with concentration of 4. 00 mmol / L,and then measure the concentration of K＋with ISE,and to calibrate the mircropipettors according to the difference between measured value and standard value,so as to verify the calibration result of ISE method by traditional weighing method. Results Convert to volume from concentration of K＋measured with 3 micropipettors calibrated by ISE,the results were respectively（ 10. 00 ± 0. 057） μl,（ 50. 06 ± 0. 409） μl,and（ 100. 17 ± 0. 890） μl,and compare them with the weighing method,the results were respectively（ 10. 20 ± 0. 326） μl,（ 50. 06 ± 0. 494） μl,and（ 100. 36 ± 0. 351） μl,and there was no statistical significance on the difference between these two methods（ P〉0. 05）. Conclusion The calibration method of micropipettor with ISE is consistent with the traditional weighing method,which is simple and easy on operation,and can be used as alternative calibration method,and promoted widely.