A fast region of interest algorithm for efficient data compression and improved peak detection in high-resolution mass spectrometry.

Liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) is commonly used for identification of compounds in complex samples due to the high chromatographic and mass spectral resolution provided. In subsequent data processing workflows, it is imperative to preserve this resolution to fully exploit the data. "Region of interest" (ROI) algorithms were introduced as a better alternative to equidistant binning for compressing HRMS data because they better preserve the mass spectral resolution.

Interference from anti-drug antibodies on the quantification of insulin: a comparison of an LC-MS/MS assay and immunoassays.

This study aims to compare the anti-drug antibody (ADA) interference in four pharmacokinetic (PK) assays across different platforms (AlphaLISA, Gyrolab, LC-MS/MS) and to devise a strategy for ADA interference mitigation to improve the accuracy of measured drug in total PK assays. Spiked test samples, created to achieve different ADA concentrations in human serum also containing an insulin analogue, were analyzed alongside pooled clinical samples using four assays. Interference was observed in all platforms.

Instrumental and theoretical advancements in pulsed elution-LC × LC: Investigation of pulse parameters and application to wastewater effluent.

Due to the decoupling of the first (D) and second (D) dimension in pulsed elution-LC × LC (PE-LC × LC), method development is more flexible and straightforward compared to fast comprehensive LC × LC where the dependencies of key parameters between the two dimensions limits its flexibility. In this study we present a method for pulse generation, which is based on a switching valve alternating between one pump that delivers the gradient and a second pump that delivers low eluotrophic strength for the pause state. Consequently, the dwell volume of the system was circumvented and 7.

Comparison of pharmacokinetic study profiles of insulin in rat plasma through conventional sampling and microsampling by micro-LC-MS/MS.

With microsamples of blood, full pharmacokinetic profiles from individual animals can be obtained as an alternative to the sparse-sampling approach, where conventional volume samples from several animals are required. However, microsamples require assays that are more sensitive. The sensitivity of the LC-MS assay was increased 47-fold using microflow LC-MS.

Source-Supported Suspect Screening (4S) of Phytotoxins in Terrestrial and Aquatic Environments: A Field Study of L. (Blue Lupin).

Phytotoxins (PTs) are bioactive secondary metabolites produced by plants. More recently, they have been recognized as important aquatic micropollutants. Despite that, only a few PTs have been detected and reported in terrestrial and aquatic environments, while their source and leaching pathways remain largely unclear.

Obtaining clean and informative mass spectra from complex chromatographic and high-resolution all-ions-fragmentation data by nonnegative parallel factor analysis 2.

A major challenge in processing of complex data obtained from chromatography hyphenated to mass spectrometry is to resolve chromatographically co-eluting compounds. In this study, we present a workflow for the resolution of ultra-high pressure liquid chromatography high-resolution mass spectrometry data obtained by the broadband data-independent acquisition MS operation (UHPLCHRMS). The workflow is based on a recently introduced algorithm for Parallel Factor Analysis 2 (PARAFAC2) that allows to enforce non-negativity on all the model coefficients.

A case study of PAH contamination using blue mussels as a bioindicator in a small Greenlandic fishing harbor.

This study investigated the impact of local anthropogenic activity on the marine environment around the remote harbor of Qeqertarsuaq, West Greenland. Blue mussels (Mytilus sp.) were used as a bioindicator, and their physiological condition was found to decrease with increasing proximity to the harbor.

Enhancing the power of liquid chromatography-Mass spectrometry for chemical fingerprinting of phytotoxins in the environment.

Phytotoxins are plant secondary metabolites. They have recently been considered as chemicals of emerging concern (CECs) and there is a growing interest in their environmental fate and potential threat to public health. Dedicated target and non-target screening (NTS) analysis of phytotoxins in environmental samples are sparse, meanwhile phytotoxins are rarely detected in NTS-based analysis due to lack of an efficient methodology.

A study of the spatial distribution patterns of airborne polycyclic aromatic hydrocarbons in crowberry (Empetrum nigrum) in Ilulissat, Greenland.

Polycyclic aromatic hydrocarbons (PAHs) are produced by anthropogenic activities, such as traffic and domestic heating. Due to their adverse effects to humans and natural habitats, the presence of PAHs in the environment needs to be monitored. Plants are known as natural accumulators of persistent organic pollutants (POPs) and can therefore be used for the monitoring of PAHs emitted into the environment.

Selective pressurized liquid extraction of plant secondary metabolites: L. as a case.

A fast and efficient selective pressurized liquid extraction (sPLE) method was developed to extract secondary metabolites from complex plant matrix. L., a plant producing toxic steroids, was used as proof-of-concept.

SPE-LC-MS investigations for the isolation and fractionation of acidic oil degradation products.

In this study, we focus on isolation and fractionation strategies by solid phase extraction (SPE) for a broad range of environmentally related organic acids. These emerging potential contaminants are primary degradation products of spilled petrogenic compounds but little attention has been given to their environmental analysis and risk assessment. Three mixed-mode anion exchange sorbents possessing various backbone polarities were compared with respect to the extraction and fractionation efficiency.

Structural isomers of polyfluorinated di- and tri-alkylated phosphate ester surfactants present in industrial blends and in microwave popcorn bags.

Introduction: In this study, we provide strategies for detecting and quantifying the structural isomers of polyfluorinated di- and tri-alkyl surfactants (PFAS) by mass spectrometry (MS). We specifically investigate polyfluorinated dialkylated phosphate ester surfactants (x:2/y:2 diPAPS, (F(CF(2))( x )CH(2)CH(2)O-P(O)(O)(-)-OCH(2)CH(2)(CF(2))( y )F)) and their thioether analogues (x:2/y:2 S-diPAPS, F(CF(2))( x )CH(2)CH(2)SCH(2)-C[CH(2)O)(2)P(O)(O)(-)]-CH(2)SCH(2)CH(2)(CF(2))( y )F), which are used for industrial applications, such as oil- and water-repellent coatings on paper and board. DiPAPS have been found in human blood and are metabolised to the persistent perfluoroalkyl carboxylic acids (PFCA) in rats.

Acrylamide-asparagine relationship in baked/toasted wheat and rye breads.

Acrylamide in baked and toasted wheat and rye bread was studied in relation to levels of asparagine in flour, dough, bread and toasts. Asparagine was consumed during bread preparation resulting in reduced acrylamide content in the products. In wheat bread, 12% of the asparagine initially present in the flour (0.