8.2.2 Analytical Method Validation for Cleaning Validation 清洁验证所用分析方法验证
In the following sections, aspects of analytical method validation specific to cleaning validation are emphasised. For further details refer to ICH Q2 (R1).
在以下部分强调了清洁验证专用的分析方法要点。更详细的要求参见ICH Q2(R1)。
Specificity is a basic requirement for all analytical methods (see Table 1), however, in the case of cleaning validation it may occur, that not all potential impurities are clearly specified. It is important to note that in such a situation a specific method may not always detect all impurities. Studies should be performed to characterise the unknown impurities, develop and validate suitable analytical methods. However, this can be an unacceptably time consuming task. In this case a method that detects all potential impurities together can be suitable, even when it is not specific for each of the impurities. For example, in a situation where only non-volatile impurities occur, a dry residue determination method that is specific for the sum of non-volatile impurities could be used, provided that the validation requirements according to Table 1 are satisfied. In order to consider the equipment acceptable for use it must be assumed that the dry residue consists of the worst case impurity (most toxic, most active etc.). In some cases a combination of several methods can achieve the necessary specificity.
专属性是所有分析方法（见表1）都适用的基本要求，但是，在清洁验证中，可能并不是所有潜在杂质都能被明确，在这种情况下要重点注意即使是专属的方法，也并不一定能检测出所有杂质。可以研究未知杂质的特性，建立适当的检验方法并验证，但这样做所耗费的时间可能是无法接受的。这时，可能会适当的办法是采用一个能检出所有潜在杂质的方法，即使该方法对有些杂质不具有专属
性。例如，如果只有不挥发性杂质产生，只要验证结果符合表1的要求，可以使用非专属性方法蒸发残渣来检测所有不挥发性杂质的总和。考虑到要使设备清洁程度可以接受，必须假定蒸发残渣结果中会包括最差情形的杂质（毒性最强、活性最强等）。有时，可以联合使用几个方法来达到必需的专属性要求。 After the completion of a cleaning validation study an unspecific method (e.g. dry residue) may be used for the routine verification of equipment cleaned by the validated cleaning procedure provided that it is shown that the unspecific method is suitable for the intended purpose. If possible, the sensitivity of impurity detection for cleaning validation should be determined for both the sampling and analytical methods together (see Section 7.2.4).
在清洁验证完成后，可以使用非专属性方法（例如，蒸发残渣）对按验证过的清洁程序清洁后的设备进行日常检测，只要该方法适合其既定用途。可能的情况下，清洁验证所用检验方法对杂质检测的灵敏度应与取样方法和分析方法一起测试（参见7.2.4部分）。
8.2.3 Detection and Quantitation Limits 定量限和检测限
Measured values below limit of quantification (LOQ) should be reported as the LOQ value (worst case approach). For example if the LOQ is 10 mg/l, the measured blank is 7 mg/l and the measured residue amount is 3 mg/l, the reported value for the sample should be equal to the LOQ i.e. 10 mg/l. 低于定量限（LOQ）应报告为定量限值（最差情况法）。例如，如果LOQ为10mg/L，测得空白结果为7mg/L，测得残留值为3mg/L，则该样品的残留值应报告为LOQ，即10mg/L。
Usually it can be assumed that, for quantitative impurity determination, the LOQ should approximately be 0.5 of the specification i.e. for cleaning validation 0.5 of the acceptance limit or lower. LOQ should never be higher
than the acceptance limit. In the following sections three methods of LOQ/LOD determination are outlined:
一般可以假定，在杂质定量检测时，LOQ应为质量标准的约0.5倍，即对于清洁验证来说，可接受限度的0.5或更低。LOD不得高于可接受限度。在以下部分，列出了三种确定LOQ/LOD的方法： ? Based on Visual Evaluation 目视评估
Visual evaluation may be used for non-instrumental methods but may also be used with instrumental methods. Frequently this approach is used for TLC.
目视评估可以用于非仪器方法，但也可用于仪器分析方法。这种方法经常用于TLC。
? Based on Signal-to-Noise Approach 信噪比方法
This approach can only be applied to analytical procedures which exhibit baseline noise (e.g. GC, HPLC). A signal-to-noise ratio (S/N) between 3 or 2:1 is generally considered acceptable for estimating the detection limit (LOD) and a typical ratio for acceptable quantitation limit is 10:1 (LOQ). The value for S/N can be calculated according to Equation 1 and Figure 1:
本方法只能用于产生基线噪声的分析方法（例如，GC、HPLC）。信噪比（S/N）为2-3：1时，一般可以作为估计的检测限（LOD），10：1可以作为定量限（LOQ）。信噪比值可以根据公式1和图1计算：
where: H is the height of the peak from the mean baseline.
hn is the maximum deviation of the baseline within the range of 5 to 20 fold width of peak at half height. 其中：H为基线平均值的峰高
hn是基线在5-20部半峰高时峰宽范围内最大偏差
? Based on the Standard Deviation of the Response and the Slope 根据响应和斜率的标准偏差
The detection limit may be expressed by Equation 2 and the quantitation limit by Equation 3.
检查限可以采用公式2表示，定量限可以用公式3表示。
8.2.4 Determination of Recovery 回收率测定
If possible, the recovery of impurity detection for cleaning validation should be determined for the sampling and analytical methods together at least for recovery and sensitivity (Limit of Quantitation - LOQ, or Limit of Detection - LOD). This can be achieved, for example, by spiking a surface equivalent to the equipment surface (e.g. material, polish grade) with different known amounts of the impurity. The impurity can then be
recovered and analysed using the same sampling and analytical methods that will be used for the cleaning validation study. The overall results from this procedure are then compared to criteria for detection or quantitation limits as defined in ICH Q2 (R1). Validation of the limits may be achieved by the analysis of samples known to be near at the limits.
可能的话，可以针对取样方法和检验方法同时进行清洁验证中杂质检测的回收率和灵敏度（定量限-LOQ，或检测限-LOD）。例如，可以采用与设备表面材质相同的表面材料（例如，材质、粗糙度），在上面加不同已知数量的杂质，然后采用与清洁验证研究相同的方法取样并分析。再将使用该方法所得的总体结果与ICH Q2(R1)中定义的检测限或定量限标准进行比较。可对接近限度的已知样品进行分析来验证分析方法的检测限和定量限。
The measured results are then compared to the actual amount applied to the surface. The recovery is typically determined during the accuracy determination and should be reported as a percentage of the known applied amount of the impurity.
将检测结果与实际数量进行比较，用于表面残留计算。回收率一般是在准确性测试中确定，应报告为已知杂质数量的百分比。
As an example, quantitative impurity determination recoveries of ≥ 90 % are usually regarded acceptable. For cleaning validation, recoveries of ≥ 90 % do not need to be taken into account for the calculation of the true value for M. Recoveries of < 90 % must be included in the calculation for M (see Equation 4) and recoveries of < 50 % should be omitted. 例如在杂质定量测试中，回收率≥ 90 %时一般认为是可以接受的。在清洁验证中，如果回收率≥ 90 %，在M残留量真值计算中可以不需要考虑回收率；如果回收率< 90 %，则需要在M计算时加以考虑（参见公式4），如果回收率<50%，则该方法不适用。