The area of integration of all peaks was normalized to the signal from the internal standard, then, after background subtraction, expressed relative to the positive control signal (100 cell equivalent) that was run with each experiment.
Specifically, if the highest background peak had an area less than 15-fold of a spiked internal standard of 500 ng/mL, then that background level was considered adequate for deployment and quantitative analysis.
Each spectrum was calibrated using the EG3-EG3 disulfide background as an internal standard, and the extent of reaction was calculated as previously reported (22).
The abundance of residual lyso-aPtdEtn molecular species was not significantly above background relative to the internal standard (spectrum not shown), indicating the low abundance of aPtdEtn molecular species in bovine heart PtdEtn.
Each spectrum was calibrated using the EG3 background disulfide as an internal standard.
Normalized values (after background extraction and normalization to internal standard) were exported from Delta2D in spreadsheet format for statistical analysis.
(i) A simple way to evaluate for systematic differences in the background matrix or an improper/suboptimal internal standard is to rerun external QC samples, both naive and also with 1 5 and 1 10 dilutions using the laboratory internal blank source.
The fingerprint scans show that the 1,372 cm−1 furfural peak is distinct from the background polymer and water phases, and each polymer phase has a strong background signal that can be used as an internal standard for peak intensity normalization.
First, the detection conditions, the background electrolyte (BGE) pH, the nature of the BGE co-ion and the internal standard (IS) were optimized by a systematic approach.
The isotopically labeled internal standard synthetic peptide and the unlabeled synthetic peptide were used to build a standard curve against the background of the non-human, complex, tryptic peptide mixture from P. furiosus.
