Non-target protein analysis of samples from wastewater treatment plants using the regions of interest-multivariate curve resolution (ROIMCR) chemometrics method

A new methodology is proposed for the non-target protein analysis of samples from wastewater treatment plants (WWTP). Proteins captured using polymeric (polycaprolactonediol) probes placed along different sites a WWTP were extracted, digested and analyzed by LC-MS/MS. Selection Regions Interest (ROI) raw MS data allowed their storage with most relevant information present in samples. Application Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) chemometrics method to ROI resolved elution profiles spectral fingerprints components Partial Squares-Discriminant Analysis (PLS-DA) peak heights these could distinguish which them changed more significantly steps WWTP. Principal Component (PCA) data, ROIMCR PLS-DA results clustering according sites. clear improvement discrimination was observed when PCA applied PLS-DA, compared obtained considering only unprocessed data. Finally, Proteome Discoverer, 281, 314, 58 peptides respectively identified at three sampling case ROIMCR, 137, 123, 31 PLS-DA. From peptides, total number 38 proteins are postulated be