Gesa Schad | Authors


Application of an LC–MS/MS Library for the Identification and Quantitation of Pesticides in Food Safety Using MRM Spectrum Mode

This article describes the application of liquid chromatography tandem mass spectrometry (LC–MS/MS) and enhanced multiple reaction monitoring (MRM) spectrum libraries for multi-pesticide residue analysis. Using these methods, a high number of fragment ion transitions of target compounds can be examined to increase specificity and reporting confidence, reducing the risk of false positive or false negative detection.

From HPLC to UHPLC — And Back

Although ultrahigh-pressure liquid chromatography (UHPLC) method development is fast and cost efficient, many of the analytical methods used in quality control laboratories are still conventional high performance LC (HPLC) separations. Transferring these HPLC methods to UHPLC and validating them is a time-consuming and labour-intensive task. Nevertheless, switching methods from HPLC to UHPLC equipment and vice versa is a powerful tool to increase laboratory efficiency. Modern systems with two flow lines in one system aim to simplify the transition between the two techniques.

Making Method Development Faster for the Analysis of Natural and Artificial Flavourings

A simple, rapid, and robust ultrahigh-performance liquid chromatography (UHPLC) method has been developed for the simultaneous determination of natural and artificial vanilla flavouring substances as well as some precursors has been developed using an automated method scouting or method optimization workflow. The most suitable mobile phase and stationary phase combination was identified in a scouting run. These conditions were used to create a two-dimensional model in computer simulation software. Temperature and gradient time were varied to establish the optimum fast and robust separation conditions. This approach resulted in a 5.5 min gradient method that allowed for fast screening of 11 compounds of interest.

Fast and Simple Determination of Free Amino Acids in Milk

Amino acids are of vital importance for human life. They serve as transport or storage media for metabolic pathways. Amino acids are components of protein-containing foods such as milk and milk products. Eight amino acids are thought to be essential for humans, meaning that they must be absorbed from foods containing animal proteins or a suitable combination of plant proteins, because the human body can’t synthesize them. Determination of the composition and content of amino acids in milk products is therefore an important measure in ensuring quality and nutritional value.

Ultra-Fast Analysis of Alkaloids and Permitted Additives in Dark Chocolate Products

A simple, rapid, and robust UHPLC method for the simultaneous determination of polyphenols, methylxanthines, sweeteners, and flavouring substances as well as some common preservatives has been developed using an automated method scouting and method optimization workflow.