Percent recovery was calculated by comparing the area before and after the addition of reference standard.
As extraction protocol involved a terminal drying step, hence spiking (addition of reference samples) was carried out in post-extracted blank plasma sample to perform AME.
This proves without a doubt that the addition of reference and retention time information drastically improves the performance, going from 22 to 89 % top 1 ranks (ChemSpider) and 6.3 to 71%% (PubChem).
Of course, we should bear in mind that these values are derived from a data set comprising only one sample per taxon, and that future addition of reference data will undoubtedly increase the fail rate.
Furthermore, addition of reference items was, in general, concomitant with increased score levels of basic reference items.
Worsening signs and symptoms related to the addition of reference items means that the general level of a patient's reference scores will increase somewhat.
A continued mode of addition of reference items could then be applied while avoiding a possible clinician-bound bias as well as an inter-mode bias of addition.
Table 5 shows the mean and SD values of TDC following treatment, for the three modes of addition of reference items.
Addition of reference items therefore occurred more frequently in patients whose treatment was unsuccessful, for example, in 84% of such patients at the last post-treatment measurement.
The effect of addition of reference items on success rate and therapy efficacy will be shown be comparing in retrospect these parameters between different modes of addition including the mode without addition.
The identification of additional metabolites will require the fractionation of cellular extracts to reduce masking by abundant metabolites, and the addition of reference compounds to the signature spectra database.
