抗生素效价测定仪校准用光谱中性滤光片的研制

根据浊度法抗生素效价测定仪吸光度的有效测量范围和液体培养基培养过程中吸光度逐渐降低的特点,选用中性灰色玻璃研制了吸光度标称值分别为0.3,0.5,0.7,1.0的光谱中性滤光片组标准物质。用紫外可见近红外分光光度计对研制的标准物质的均匀性、正反面和稳定性进行测试,吸光度均匀性最大值为0.002 0,吸光度正反面最大差值为0.000 4,吸光度稳定性最大值为0.002 5,符合二级标准物质要求,经评定标准物质吸光度的相对扩展不确定度为1%(k=2)。将该标准物质的定值结果与上一级计量标准中国计量科学研究院的校准结果进行比对验证,结果表明研制的标准物质定值准确,可用于抗生素效价测定仪吸光度准确性和溯源性校准。

Preparation of Reference Material for Spectral Neutral Filters to Calibrate Antibiotics Potency Analyzer

According to the characteristics with the absorbance measuring range and the absorbance decreasing in the cultivation process of the antibiotics potency analyzer,the reference materials of spectral neutral filters with absorbance nominal values of 0.3,0.5,0.7 and 1.0 were prepared by using neutral grey glasses. The absorbance homogeneity, directivity and stability of the reference materials were tested by using an ultraviolet visible near infrared spectrophotometer. The maximum absorbance homogeneity was 0.0020,the maximum absorbance directivity was 0.0004,and the maximum absorbance stability was 0.0025,meeting the reference material 2nd level requirement. By evaluation,the relative expanded uncertainty of the reference material absorbance was 1％(k=2). The determination results of this reference material were compared with the calibration results of the previous level measurement standard (National Institute of Metrology , China),the results validated that the absorbance of the reference material was accurate. The reference material can be used to calibrate the absorbance accuracy and traceability of antibiotics potency analyzer.