A calibration transfer methodology for Standardization of Raman instruments with different spectral resolutions using Double Digital Projection Slit

A calibration transfer procedure is necessary when the established chemometric models are utilized to predict samples measured on different instruments. However, the existing methods are always ineffective for Raman instruments with different spectral resolution. We introduce a simple and reliable calibration transfer method based on Double Digital Projection Slit (DDPS), which can standardize the spectral resolution between different Raman instruments. The DDPS method is validated based on the pharmaceutical and liquid samples measured on two Raman instruments. The resolution of the primary instrument is about 3 times higher than the secondary instrument. Transfer is considered successful since the correlation coefficient (R) and root mean square error of prediction (RMSEP) are close to the corresponding primary prediction results. An attractive potential application of the DDPS method is to improve the prediction accuracy of an ordinary instrument by using the calibration model from a precise instrument with high resolution.