移液管和移液枪在化学分析中对检测结果影响的比较

Comparison of the measuring accuracy between pipette and locomotive pipette in chemical analysis

本文通过分别使用移液管和移液枪对标准溶液样品进行稀释,然后对稀释后样品进行检测和结果的比较,验证了移液管和移液枪对检测结果准确度的影响。结果表明,使用移液管稀释的样品,其检测结果与标准值之差都在标准值的不确定度范围(1%)以内;使用移液枪稀释的样品,其检测结果与标准值之差都远高于标准值的不确定度范围(1%)。这表明,在正确使用移液器具的前提下,用移液管稀释的样品的检测结果准确度远远高于用移液枪稀释的样品。建议在化学分析检测工作中,尤其在稀释或定容的过程中,尽可能使用移液管。

We report our investigation on possible discrepancy between using pipette and locomotive pipette in terms of measuring accuracy by using pipette and locomotive pipette to dilute the same standard solutions and comparing their test results.The results indicated that the differences between the test results and the pre-determined concentrations were well within the allowable range of uncertainty(1%)when using pipette to dilute samples,while,however,the differences between the test results and the pre-determined concentrations were significantly higher than the allowable uncertainty range(1%)when using locomotive pipette to dilute test samples.Our results demonstrated that the test results from using pipette were more accurate than that from using locomotive pipette and we therefore recommend using pipette rather than locomotive pipette to dilute all solutions in chemical analysis.