Coffee is one of the most widely consumed beverages in the world, partly because of the stimulating effect of its caffeine content. Like most crops, the application of pesticides in coffee cultivation is a common practice to increase production yields. This application note details an optimized method for the extraction and cleanup of pesticide residues from coffee using a QuEChERS extraction procedure followed by a silica gel solid-phase extraction (SPE) cleanup.
While on-line multi-angle light scattering (MALS) is one of the most important techniques for macromolecular characterization, it can be made even more versatile with the addition of a quasielastic light scattering (QELS, a.k.a. dynamic light scattering) module for determination of hydrodynamic radius. QELS can be added to a Wyatt MALS system as a WyattQELS™ module embedded in the MALS instrument, or by connecting the MALS flow cell to a batch DLS instrument such as a DynaPro® NanoStar® or Mobius® via optical fibre. The QELS instruments can be used to determine the hydrodynamic radius, rh , for a variety of samples in a continuous‑flow mode. The combined MALS-QELS system will measure simultaneously rg, rh, and the absolute molar mass.
Click the title above to open the LCGC Europe July 2017 regular issue, Vol 30, No 8, in an interactive PDF format.
Click the title above to open the LCGC North America July 2017 regular issue, Vol 35 No 7, in an interactive PDF format.
Click the title above to open the July 2017 issue of Current Trends in Mass Spectrometry, Volume 15, Number 3, in an interactive PDF format.
I believe that the term “top-down proteomics” holds a particular connotation with respect to the use of ultrahigh-resolution mass spectrometers in people’s minds. And rightfully so. If one is to determine with confidence the sequence and charge state of a particular fragment ion generated in the gas phase, then high mass accuracy is a must. From the discovery side of things, where qualitative analysis is most important, this is not likely to change. However, when you turn to quantitative analysis, where you want to now monitor levels of a particular protein biomarker for the purpose of disease diagnosis, prognosis, or treatment, then invariably bottom-up strategies are the norm. Protein quantitation using top-down strategies, especially on low-resolution triple-quadrupole systems, have been largely ignored, until recently .
Thermo Fisher Scientific has been selected as a partner of INTELLItrace Work Package (WP) 18, part of the European Food Integrity Project aimed at developing a validation of untargeted methods to assure the quality, authenticity, and safety of the food chain.
Researchers have developed and validated a stability- and potency-indicating assay protocol for high-throughput quality assessment of vaccines consisting of recombinant virus- “like” particles (VLPs) using conformation-dependent antibodies coupled to size-exclusion high performance liquid chromatography (SE-HPLC).
Fluence Analytics, formerly Advanced Polymer Monitoring Technologues (APMT), has announced an increase in investment led by Energy Innovation Capital (EIC) but also including participation from other investors.
Researchers from the Chinese Academy of Science in Beijing, China, have used high‑performance size-exclusion chromatography (HPSEC) and differential scanning calorimetry (DSC) to study the stabilization of inactivated foot and mouth disease virus.
Antibody–drug conjugates (ADC) are an emerging pharmaceutical technology, with the potential of being the true “magic bullet”. However, these inherently complex biomolecules have unique analytical challenges. One is the determination of the drug-to-antibody ratio (DAR). The average DAR and the drug distribution need to be monitored and could determine the success of an ADC. This article discusses the chromatographic methods used to determine DAR, including hydrophobic interaction chromatography (HIC), reversed phase, and liquid chromatography–mass spectrometry (LC–MS).
Dynamic light scattering (DLS), widely recognized for its ability to detect aggregation in purified protein solutions, is actually far more versatile and may be applied to the evaluation of stability and viscosity of therapeutic proteins and other biopharmaceuticals. In a fully automated, microwell plate reader format, DLS constitutes a high-throughput biophysical screening technique for early-stage assessment of candidate developability and optimal formulation conditions.
Click the title above to open The Column June 20, 2017 Europe & Asia issue, Volume 13, Number 9, in an interactive PDF format.
Click the title above to open The Column June 20, 2017 North American issue, Volume 13, Number 9, in an interactive PDF format.
When you want to adjust a United States Pharmacopeia (USP) method for a different size column or to meet system suitability criteria that fail, how much of a change can you make without revalidating the method?
The quantitative extraction and subsequent purification of trace contaminants from (semi-)solid environmental and food matrices of regular size (that is, a few grams) is still recognized as a challenging task, typically accomplished through relatively complex off-line multistep treatment procedures. When these conventional sample preparation procedures are applied to the treatment of size-limited samples (of less than 1 g), the difficulties increase. This review discusses the different analytical strategies that can be adopted to overcome (or at least reduce) these difficulties when chromatographic techniques are involved for final instrumental determination.
hermo Fisher Scientific has announced its intention to buy Patheon NV.
A novel unit that integrates sampling and analysis for the determination of pest insect sexual pheromones in environmental air using fabric phase sorptive extraction (FPSE) and headspace gas chromatography coupled to mass spectrometry (HSGC–MS) has been developed at the University of Córdoba in Spain.
MilliporeSigma is now accepting entries for the Alfred R. Bader Award for Student Innovation.
Peak Scientific has expanded its operations in Latin American (LATAM), moving to a new, larger premise with the aim of developing its support capabilities in the growing LATAM market.
Molecular mass is one of the central parameters required for product registration. Compared to low molar mass substances, the molar mass determination of macromolecular products is more difficult because the product is a mixture of chains with different lengths and, therefore, molar masses. Gel permeation chromatography/size-exclusion chromatography (GPC/SEC) is the standard technique to separate macromolecules by size and to measure the complete molar mass distribution as well as the molar mass averages. This technique therefore provides crucial information for product registration, including REACH.
A preview of HPLC 2017, which will be held from 18 to 22 June 2017 at the Prague Congress Centre, Prague, Czech Republic.
Analysis of residual antimicrobials in animal products is crucially important to ensure food safety. This article presents a simple, fast, and highly sensitive high performance liquid chromatography (HPLC) assay of regulated antimicrobials, as well as sample preparation and purification methods. Twenty-four different analytes of interest were investigated in beef, pork, and chicken meat samples.
Successful therapeutic intervention often requires chiral medicines because of the intrinsic chirality of protein drug targets, which consist of L-amino acids. Potency, efficacy, and safety can be highly dependent on the precise stereochemical geometry of the molecules. Determining the biological profile of individual enantiomers in the early stages of drug discovery is important for successful optimization towards clinical candidates. Here we demonstrate the benefits of supercritical fluid chromatography (SFC) with three chiral stationary phases exemplified by high frequency resolution of 41 out of 50 chiral derivatives of eight commonly used drug discovery scaffolds including 1,3-thiazoles, 1,3-benzothiazoles, pyranoquinolones, indoles, and leucolines.
A preview of the HPTLC 2017 symposium, which will take place this July.
Click the title above to open The Column June 06, 2017 Europe & Asia issue, Volume 13, Number 8, in an interactive PDF format.
Click the title above to open The Column June 06, 2017 North American issue, Volume 13, Number 8, in an interactive PDF format.
