A method for the quantitative chemical analysis of samples, comprising the following stages:
- providing a specific detection instrumentation or apparatus to be used for quantitatively detecting the target analytes present in the samples that will be analyzed, said specific detection apparatus comprising a chromatography system, an ion source and a mass spectrometer;
- preliminarily defining, before the actual quantitative analysis of the samples, a database containing data and corrective and/or control coefficients to be used for calibrating the instrumental response of said specific detection apparatus,
- said data and said control coefficients being determined by detecting by means of said specific detection apparatus the quantitative data of given calibrating substances and commercial standards of the target analytes;
- and
- determining the results of the analyses of the samples, namely the final quantitative data of the target analytes present in each sample analyzed, by processing, while taking into account said data and corrective and/or control coefficients contained in said database, the quantitative data, as detected by said specific detection apparatus, of the target analytes in the sample analyzed;
- whereby the analysis final quantitative data and results of the samples are determined without calibrating the specific detection apparatus before analyzing each sample,
- wherein the stage of preliminarily defining said database comprises the stage of:
- acquisition by said database of a first corrective and/or control coefficient defined by the following formula:
- K=I0/I,
- where K is said first corrective and/or control coefficient, I0 is the theoretical signal corresponding to given calibrating substances, and I is the signal that is obtained by sampling and quantitatively analyzing said calibrating substances by means of said specific detection apparatus intended to be used for analyzing samples,
- whereby said first corrective and/or control coefficient K, acquired by said database, is characteristic of the type and model of said specific detection apparatus used for analyzing the samples,
- and also comprises the stage of:
- acquisition by said database of a second corrective and/or control coefficient defined by the following formula:
- C=V*(Ix*K), or C=V*[Ix*(I0/I)],
- where C is said second corrective and/or control coefficient, V is an instrumental variable that is dependent on the specific detection apparatus that is used and in particular is distinctive of its instrumental response, and Ix is the signal that is obtained by detecting, with said detection apparatus, the quantitative data of commercial standards of the target analytes to be quantified in the samples,
- whereby said second corrective and/or control coefficient C, acquired by said database, is characteristic both of the specific detection apparatus used for analyzing the samples, and of the specific target analytes to be quantified in the samples analyzed,
- wherein, in said stage of determining the results of the analyses of the samples, the final quantitative data or results of the quantitative analysis of the target analytes present in the sample analyzed is determined by the data processing system with the following formula:
- Cp=C1*Ip/Ix,
- where Cp corresponds to the unknown concentration, to be determined, of the target analyte, Ip is the known intensity of the signal generated by said unknown concentration Cp, and C1 is a further coefficient defined by the following formula:
- C1=K1*C=K1*[V*(K*Ix)],
- implying Cp=K1*V*K*Ip,
- where K1 is a further third control coefficient which is suitable for evaluating the matrix effect in the analyzed sample, and
- wherein the method also includes the stage of:
- preparing the samples to be quantitatively analyzed by diluting the original samples in a suitable universal dilution solution in order to minimize the corresponding matrix effect.