Spectroscopic solution for non-destructive quantification of one or more chemical substances in a matrix comprising coating and bulk material in a sample, such as coated seeds, using multivariate data analysis

A computer-implemented method for provision of a calibration for a chemical substance to be quantified in a matrix, said matrix being defined by its further coating components and said bulk material, wherein said calibration comprises conducting spectrum pre-treating steps and a multivariate data analysis using a multivariate correlation model for the correlation of a near-infrared, infrared or a Raman spectrum signature relevant for the chemical substance in the matrix and a reference loading value for the chemical substance in said matrix in consideration of matrix influences, said method comprising the following steps:

• a. acquiring a training data set comprising a plurality of spectra representative of training samples and reference loading values measured for the chemical substance in the training samples, wherein the training samples are selected using a method for design of experiments so that, the reference loading values for the chemical substance and matrix influences are distributed homogeneously within a variation room delimited by its boundaries;
• b. normalizing the plurality of spectra of the training data set and selecting normalized spectrum signatures within a range of interest for the chemical substance;
• c. computing a multivariate correlation model based on the normalized spectrum signatures and the reference loading values of the training data set under consideration of the matrix influences using multivariate data analysis;
• d. computing a standard deviation for predictions provided by the multivariate correlation model from the reference loading values;
• e. reiterating step b. to d. until minimal standard deviation for prediction is achieved;
• and
• f. saving the normalizing steps and the trained correlation model with minimal standard deviation as the calibration for multivariate data analysis for the chemical substance to be quantified in the matrix.

A system for non-destructive quantification of one or more chemical substances of interest coated on bulk material in a matrix, said matrix being defined by its further coating components and said bulk material, said system comprising:

• a memory storing one or more instructions;
• a repository storing one or more calibrations, wherein said calibration is specific for the chemical substances to be quantified in the matrix and wherein said calibration comprises conducting spectrum pretreating steps and a multivariate data analysis using a multivariate correlation model trained for computing a loading value of the chemical substance(s) based on a signature spectrum relevant for the chemical substance(s) at stake in consideration of matrix influences;
• and
• one or more processors configured to execute the one or more instructions which, when executed by the one or more processors, cause performance of:
• acquiring one or more spectrum representative of the sample, wherein said spectrum is a near-infrared, infrared or a Raman spectrum;
• selecting one or more calibration for multivariate data analysis based on the one or more chemical substances to be quantified;
• computing the spectrum signature relevant for the chemical substance(s) by way of running the spectrum pretreating steps of the one or more calibration(s) for the one or more spectrum representative of the sample;
• computing a loading value of the chemical substance(s) using the correlation model(s) of the one or more calibrations;
• and
• causing displaying on a user interface of the computed loading value of the chemical substance(s).