Validation parameters

The linearity of a method is its ability to obtain test results that are directly proportional to the sample concentration over a given range. For HPLC methods, the relationship between detector response (peak area or height) and 

Assay and content five levels correlation coefficient, R 

Related substances five levels LOQ to acceptance criteria R 0.99  

Bioanalytical six to eight levels covering the dynamic range R 0.99  

Accuracy is the closeness in agreement of the accepted true value or a reference value to the actual result obtained. Accuracy studies are usually evaluated by determining the recovery of a spiked sample of the analyte into the matrix of the sample (a placebo) or by comparison of the result to a reference standard of known purity. If a placebo is not available, the technique of standard addition is used. 

---

Analytical methods submitted by applicants are evaluated using harmonized criteria (see Section 2.5). The following presentation provides a brief overview of the validation parameters used in the registration of plant protection products and their a.i. These parameters are as follows ... 

Table 4 Validation parameters and criteria appUed for the assessment of enforcement analytical methods...

As mentioned above, the speciflcity, precision, recovery, and LOQ must be experimentally determined and reported for each method and for each relevant representative matrix. In Table 4 brief explanations are given to describe the validation parameters in... 

The general sample set for method validation parameters is the same for all matrices under consideration (except body fluids and tissues, see Section 4.2.5) ... 

Komit6 for Levnedsmidler (NMKL)]. The standard presents a universal validation approach for chemical analytical methods in the food sector. This includes methods for the main constituents and also for trace components. Therefore, the NMKL procedure focuses on primary validation parameters, such as specificity, calibration, trueness, precision, LOD or LOQ and does not refer to special requirements of pesticide residue analysis. 

Figure 16.4. Quantification of A9-tetrahydrocannabinol (9THC) after TFA and 11-nor-9-carboxy-A9-tetrahydrocannabinol (THCCOOH) after PFP in blood using GC-MS/NCI. Drug-free blood was spiked with 9THC (a) and THCCOOH (b) to the concentrations of 0, 5, 10, and 50 or 20ng/mL and with ISs-9THC-D3 and THCCOOH-D3 to 20ng/mL. Monitoring ions were (m/z) 410.3 for 9THC and 572.3 for THCCOOH. The values of validation parameters, expressed in ng/mL, were LOD, 0.25 LOQ, 0.5 limit of linearity, 0.5 to 100 for both analytes [2].

Some validation parameters of the method are listed in Table 2.26. It was further established that the sensitivity is higher under positive-ion than under negative conditions [69],... 

The validation parameters of the method such as linearity, precision, accuracy, specificity and robustness were good, therefore, the method has been proposed for commercial control laboratories [148]. 

A typical chromatogram representing the separation of Hypericum perforatum extract with the HPLC-MS attributions of the components detected is shown in Fig. 2.49. The validation parameters of the method (linearity, stability, reproducibility of the injection integration and repeatability, and robustness) were acceptable, therefore, it was found suitable for routine analysis of the composaition of the extracts of Hypericum perforatum [149],... 

The amounts of analytes are compiled in Table 2.74. The results indicated that the concentration of polyphenols in red wines depends on both the grape variety and on the exogenous factors. The validation parameters of the method were good, the recoveries were in each case over 98 per cent, the coefficients of variation were between 1.3 per cent and 4.3 per cent, and the limit of detection ranged from 10/rg/l to 0.1mg/l. It was stated that the method is suitable for the determination of silbene compounds and quercetin in red wines [194],... 

Because of the good validation parameters, the RP-HPLC method combined with SPE has been proposed for the investigation of the pharmacokinetics of RCA in plasma and brain [108],... 

Ponceau 4R, E-124 and Erythrosine, E-127) using a buffered mobile phase. Separation of dyes was performed in an ODS column (150 X 3.9 mm i.d. particle size 3 pm). Components of the mobile phase were methanol (eluent A) and 0.1 M NaH2P04/Na2HP04 buffer (pH = 7). The gradient elution started with 20 per cent A and reached 100 per cent in 2 min, final hold 4 min. The flow rate was 2 ml/min and dyes were detected at 520 nm. The baseline separation of dyes in 6 min is illustrated in Fig. 3.34. Commercial samples were diluted and injected into the analytical column without any pretreatment. The amounts of dyes found in the samples are compiled in Table 3.20. It was concluded from the good validation parameters that the technique is specific, sensitive, accurate and rapid. Consequently, its application for the determination of these synthetic dyes in drinks was proposed [112],... 

Validation Parameter Identification Impurities (Quantitation) Impurities (Limit) Assay... 

TABLE II Validation Parameters for Different Types of Analytical Test Methods... 

This chapter focuses on approaches to the validation of high-performance liquid chromatography methods based on regulatory guidance documents and accepted industry practices. The information in this chapter gives a brief review of the reasons for performing method validation and the regulations that describe this activity. Individual validation parameters are discussed in relation to the type of method to be validated. Examples of typical validation conditions are presented with references to additional information on individual topics. This chapter was written to help analysts responsible for method validation. 

Validation parameter Assay Category 1 Assay Category II Quantitiative Assay Category II Limit test Assay Category III Identification... 

Methods used to determine the performance characteristics of finished products fall into Category III. Dissolution tests (excluding measurement) and drug release tests are examples of these types of methods. Precision is the only parameter required for these methods according to the regulatory guidances, although all validation parameters may be determined based on the intent of the method. 

Reproducibility is the third and final portion of precision testing. Here, samples are prepared and compared between testing sites. This usually occurs at the time of technology transfer. Samples are prepared in a similar manner between the two sites and are compared to a previously agreed-upon set of acceptance criteria. As per the ICH, reproducibility studies are not a part of submission filings, but should be performed as a confirmation of the ability of each testing site to perform the method reliably. An executed reproducibility study can be used in place of intermediate precision for the validation of a method, although there is no problem if both validation parameters are evaluated. 

System suitability is probably one of the least understood validation parameters. The well-trained analyst should know that setting proper and... 

---