Calibration Transfer and Instrument Standardization

Consider the following scenario, which is very common in PAT deployments. 

To minimize calibration development costs, it would be ideal to produce a calibration using data obtained on only one of the analyzers (the master instrument), and simply transfer this calibration to all of the other analyzers (the slave instruments). 

At this point, it is worthwhile to discuss the distinctions between the two strategies that are commonly used in these scenarios  

Although both of these strategies are used under similar circumstances, and have similar goals, they differ in the specihc entity that is adjusted the instrument data versus the calibration. 

Once the specific nature of inter-instrument variability is assessed, it is possible to develop a transfer strategy. An important part of this strategy involves the selection of an appropriate set of transfer standards. In general, these standards should  

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Concurrent with the selection of transfer standards is the selection of the optimal strategy deciding whether to use calibration transfer or instrument standardization, assigning the master and slave instruments, and selecting a suitable transfer algorithm. Some commonly used algorithms for calibration transfer and instrument standardization are discussed below. 

Multiway methods For analyzer data where a single sample generates a second order array (ex. GC/MS, LC/UV, excitation/emission fluorescence), multiway chemometric modehng methods, such as PARAFAC (parallel factor analysis) [121,122], can be used to exploit the second order advantage to perform effective calibration transfer and instrument standardization. 

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