All News

figure 11505490994360.png

The Application Notebook

“Click” chemistry is a class of efficient and selective reactions that is characterized by quantitative yields, tolerance to a broad range of functional groups, facile experimental setup, and minimal synthetic workup. This class of reactions combines particularly well with controlled radical polymerization methods, such as atom transfer radical polymerization (ATRP), and the two techniques have been prolifically employed for the synthesis of a wide variety of novel polymeric materials, including (multi) block copolymers, stars, brushes, and gels. This note describes the analysis of multisegmented block copolymers prepared by click-coupling of block copolymers synthesized by ATRP.

figure 11506072274107.png

The Application Notebook

Liposomes are often used as nanocarriers to encapsulate in their cores hydrophobic or highly toxic drugs, and deliver these drugs safely to target tissue. During drug nanocarrier research and development as well as production quality control, it is of great importance to monitor liposome size distributions accurately while also verifying drug encapsulation. FFF-MALS-DLS, consisting of field-flow fractionation (FFF) combined with multi-angle light scattering (MALS) and dynamic light scattering (DLS), is a powerful tool for characterizing the size, concentration, and structure of large nanoparticle ensembles.

figure 11506073884678.png

The Application Notebook

Modern therapeutic antibody formats, such as bispecific antibodies (bsAbs), are on the rise. Bispecific antibodies are artificial proteins that recognize two different epitopes and can simultaneously bind to two different types of antigen. They can be used to redirect T cells to tumour cells, block two different signalling pathways simultaneously, dually target different disease mediators, and deliver payloads to targeted sites.

chromsoc.jpg

LCGC Europe

ChromSoc’s Advances in Gas Chromatography meeting will take place at The Heath Business and Technical Park, Runcorn, Cheshire, UK, on 18 October 2017.

Olive oil.jpg

The Column

A method to determine the quality of olive oil has been developed using a novel atmospheric pressure chemical ionization (APCI) source in combination with gas chromatography (GC) coupled to hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS) and a metabolomics strategy.

Cocao.jpg

The Column

Researchers from the Université de Strasbourg, France, have developed a method to discover cocoa bean origin by analyzing chocolate polyphenols using high performance liquid chromatography–diode array detection–mass spectrometry.

cookies.jpg

The Column

This proof-of-principle study shows that dynamic headspace sampling with thermal desorption–gas chromatography–time‑of-flight mass spectrometry (TD–GC–TOF-MS) analysis can be used to investigate the complex aroma profiles released from flavoured cookies. Key flavour compounds in chocolate-chip, peanut, and orange-cream cookies are highlighted, and the effect of raising the headspace extraction temperature is examined.

figure 1 L1503418634328.png

The Column

A rapid and sensitive ultrahigh-pressure liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) method was developed to simultaneously determine six plant growth regulators in bean sprouts with a simple preparation. Analyte extraction from samples was effectively performed using liquid–liquid extraction (LLE) by acetonitrile. Chromatographic separation was conducted on a C18 reversed-phase column with gradient elution. The analytes were detected by tandem quadrupole MS after negative electrospray ionization by multiple reaction monitoring. The developed method was validated by testing method specificity, matrix effect, sensitivity, linearity, accuracy, and precision.

RAFA.jpg

The Column

A preview of RAFA 2017, which will be held 7–10 November 2017 in Prague, Czech Republic.

tips and tricks.jpg

The Column

Combinations of detectors are often used in gel permeation chromatography/size-exclusion chromatography (GPC/SEC) to measure absolute molar masses or chemical compositions as a function of elution volume. Such multidetector setups require the correction of the delay volume between the detectors for correct data processing. This instalment of Tips & Tricks explains more.