Calibration procedures summary

In summary, this chapter reviews how to develop expedited calibration procedures and acceptance criteria for all the common modules in an HPLC system. 

Detailed description of "calibration procedure is given on pp 4-26. Fig 2A, p 6 (not reproduced here) illustrates the "Test Set-Up for Obtaining the Shock Velocity with a Smear Camera and Fig 3A, p 8 "Smear-Camera Set-Up for Measuring Free-Surface Velocity , "Summary and Conclusions are given on pp 24-6 and Refs on pp 27-8 of the report... 

Required Protocols and Procedures for Parenterals Production Calibration Program Summary Preventive Maintenance Program Summary Key SOPs... 

Equipment information sheets summary Name and location of equipment Model and serial number of equipment Purchase order for equipment/contract numbers Number and location of SOPs Number and location of calibration procedure Number and location of maintenance procedure(s)a Materials that come in contact with the product Lubricants General comments Safety comments... 

For MTDSC, it is also essential to calibrate for the reversing heat capacity to allow quantification of the deconvoluted results. There are several approaches by which this may be achieved, with more accurate methods requiring greater sophistication and more time hence, a decision needs to be made with regard to how important accurate heat capacity data are to the objectives of the study. For most pharmaceutical applications, fairly simple calibration procedures such as those about to be outlined are usually sufficient. However, for more accurate work it is essential to use more detailed approaches such as that described in Reference 11. In this summary, we outline only the simple approaches, but readers should be aware of the availability of more complex methods that yield more reliable results. 

System calibration refers to the periodic operational qualification of the HPLC, typically every 6 to 12 months in most regulated laboratories. This calibration procedure is usually coordinated with an annual preventative maintenance (PM) program and is performed immediately after PM. A calibration sticker is placed on the instrument to indicate its calibration status and readiness for GMP work. The reader is referred to the principles and strategies behind HPLC calibration criteria published elsewhere.8 A summary of the calibration procedures and acceptance criteria, including additional procedures recommended for initial operational qualification, is listed in Table 9.3. 

Required protocols and procedures for parenterals production Calibration program summary Preventive maintenance program summary Key SOPs... 

In summary, official German analytical methods for pesticide residues are always validated in several laboratories. These inter-laboratory studies avoid the acceptance of methods which cannot readily be reproduced in further laboratories and they do improve the ruggedness of analytical procedures applied. The recently introduced calibration with standards in matrix improves the trueness of the reported recovery data. Other aspects of validation (sample processing, analyte stability, extraction efficiency) are not considered. 

The main goal of this section is to provide a summary of several of the most widely used multivariate procedures in food authentication out of the vast array currently available. These are included in well-known computer packages such as BMDP, IMSL, MATLAB, NAG, SAS, SPSS and STATISTIC A. The first three subsections describe unsupervised procedures, also called exploratory data analysis, that can reveal hidden patterns in complex data by reducing data to more interpretable information, to emphasize the natural grouping in the data and show which variables most strongly influence these patterns. The fourth and fifth subsections are focused on the supervised procedures of discriminant analysis and regression. The former produces good information when applied under the strictness of certain tests, whereas the latter is mainly used when the objective is calibration. 

Calibration is used here to describe whatever process is used to relate observed spectral frequencies and intensities to their true values, and validation is a procedure to verify the calibration and determine the magnitude of experimental error. Raman spectroscopy is a demanding technique in terms of reproducibility and accuracy and involves a variety of instrumental configurations. Calibration is often the source of irreproducibility and inconsistency in reported Raman spectra. This chapter is divided into four general sections frequency calibration (10.2), response function calibration (10.3), absolute response calibration (10.4), and a summary of procedures (10.5). For each section, standards and procedures for instrument validation are considered. 

At the technical meeting, it was recalled that strict observance of the extraction protocol would be a criterion for considering the results for discussion. The participants recommended that a tolerance of 30% be included in the extraction protocol for the shaker speed. Most of the errors detected were rather due to e.g. calibration errors than to the application of the extraction procedure. A summary of the statistical evaluation is given in the certification report [25]. The certified values and their uncertainties are given in Tables 9.7a-c as mass fractions of the respective extracts obtained at the first, second and third steps in mg kg (based on dry mass). 

Table 9.3. Summary of Typical HPLC Calibration Test Procedures and Acceptance Criteria... 

The Contract Laboratory Program procedure required delivery of specified documents included data summary forms, calibration data, chromatograms, and mass spectra and were generally shipped by air freight. Upon receipt by EPA, the documents were reviewed for data usability which was based on consideration of completeness of documentation and adherence to quality control requirements... 

For the maximum benefit to the participants and the technical discussion, the organizer should prepare summaries of method descriptions including information on the most critical steps in the analytical procedures, e.g. calibration, pre-treatment, extraction and clean-up, separation and final detection. If possible, the methods described in brief should be presented in the form of simple table showing the most important parameter grouped by item or analytical step. 

Figure 1.2 Summary of the several steps that must be integrated in an overall optimized quantitative analytical procedure. (Note that a mass spectrometer, although a key component, appears only in the Instrumental Analysis steps (and to some extent in the purity analysis of the calibration standard)).

Before a suite of samples can be analyzed, a set of protocols, similar in design to other U.S. EPA ICP-MS analytical procedures such as Method 200.8, must be followed to ensure the instrument is working at its optimum performance. A summary of these protocols is shown in Table 20.2. The analytical run sequence outlined should be performed on a daily basis in order to meet all quality control requirements. (Note The samples shown in the top portion [sequence 1-19] must be run once per sequence, while the 10 samples [sequence 20-22] and the final continuing calibration verification [CCV] and continuing calibration blank [CCB] samples must be repeated.)... 

Calibration curves were determined for five different concentrations of tinidazole standard solutions under these two wavelengths. Each calibration sample was detected in triplicate. According to the above standard procedure, the calibration curves were obtained by plotting the concentration of tinidazole against the intensity of RLS spectra at 452.0 and 569.5 nm (Figure 6). Table 3 lists the parameters and correlation coefficients of the calibration plots with two wavelengths. The A/(y) and the tinidazole concentrations (x) were fit to the linear function. The results of the regression analysis were then used to back-calculate the concentration results from the A/, and the back-calculated concentrations and appropriate summary statistics (mean, standard deviation (SD), and percent relative standard deviation (RSD)) were calculated and presented in tabular form. 

Quantitative analysis. Preparation of standards containing known amounts of the analyte(s) or of pure reagents to be reacted with the analyte(s). Calibration of instruments to determine the responses to the standards under controlled conditions. Measurement of the instrumental response for each sample under the same conditions as for the standards. All measurements may be replicated to improve the reliability of the data, but this has cost and time implications. Calculation of results and statistical evaluation. Preparation of report or certificate of analysis. This should include a summary of the analytical procedure, the results and their statistical assessment, and details of any problems encountered at any stage during the analysis. 

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