Author


Andre J. Nohl

Latest:

30-s UHPLC Separation of Pharmaceutical Ingredients using PDA Detection

Ultra fast separations of acetaminophen, caffeine, propofol and parabens are achieved in 30 s using the Thermo Scientific Accela UHPLC system with the 80 Hz PDA detector. The performance of the Accela PDA detector is highlighted by its low noise level, low drift, four orders of magnitude linear working range and high sensitivity.


Klaus Zwiorek

Latest:

Analysis of Polymers and Protein Nanoparticles using Asymmetrical Flow Field-Flow Fractionation (AF4)

This article describes some of the latest developments for the analysis of polymers and nanoparticles.


Achille Cappiello

Latest:

The Benefits of a Liquid-Electron Ionization Liquid Chromatography–Mass Spectrometry Interface

This is the fourth in a series of articles exploring current topics in separation science that will be addressed at the HPLC 2019 conference in Milan, Italy, from 16–20 June.


S. Lemeer

Latest:

Enhancing Phosphotyrosine Proteome Coverage Using a Combined ETD and CID Approach on a LTQ Orbitrap XL ETD

Collision-induced dissociation (CID) and electron transfer dissociation (ETD) are complementary mass spectrometric fragmentation techniques. We have used CID and ETD in different approaches to analyse tyrosine phosphorylation using a Thermo Scientific LTQ Orbitrap XL equipped with ETD.


Steve Scheuring

Latest:

How To Buy Gas Calibration Mixes

In January 2004, LCGC Europe published an article on methods for selecting pure gases for analytical applications. 1 Here, the authors expand on this topic by addressing questions regarding gas mixtures - defined simply as more than one gas in a cylinder.


Richard Fussell

Latest:

Rapid Analysis of Pesticides in Difficult Matrices Using GC–MS–MS

Pesticides are widely used in agriculture to protect crops and to improve efficiency of production. Consequently, governments, food producers and food retailers have a duty to ensure that any residues occurring in foods for human consumption are at or below statutory maximum residue levels (MRLs). Regulation EC 396/2005 adopted in the European Union sets MRLs for more than 500 different pesticides in over 300 different food commodities.


Ronei Jesus Poppi

Latest:

GCxGC-FID for Qualitative and Quantitative Analysis of Perfumes

Exploring the use of GCxGC-FID as a technique for qualitative and quantitative analysis of perfumes


Merck SeQuant AB

Latest:

Separation of Quaternary Ammonium Compounds Using a Bonded Polymeric Zwitterionic Stationary Phase

Using a bonded polymeric zwitterionic stationary phase, in HILIC mode, polar quaternary herbicides like Diquat can easily be retained, with good peak symmetry. The impact of ionic strength and organic content in the mobile phase is discussed.


Guido Aerts

Latest:

Real-Time Profiling of Volatile Malt Aldehydes Using Selected Ion Flow Tube Mass Spectrometry

The authors use headspace SIFT-MS to target and identify volatiles in various malt aldehydes. The specificity and speed are compared to current methodology.



Ruud J.P. Goedknegt

Latest:

Certificates for Chromatography Standards: Sense and Nonsense

There is more to using and interpreting certificates for chromatography standards than meets the eye


Karine Jacq

Latest:

Method Selection for Trace Analysis of Genotoxic Impurities in Pharmaceuticals

This article describes methods to quantitatively analyse genotoxic and potentially genotoxic impurities in pharmaceutical ingredients


Corky Belobraydich

Latest:

Generating Make-Up Gas for GC with an In-House Nitrogen Generator

Since the gas flow required for the separation step in gas chromatography is frequently lower than that required to optimize the detection, nitrogen is used as a make-up gas to increase the gas flow for detection.


Görkem Mergen

Latest:

Simultaneous Headspace-GC–FID Analysis for Methanol and Ethanol in Blood, Saliva and Urine: Validation of Method and Comparison of Specimens

A simultaneous headspace-GC–FID method was validated to establish methanol and ethanol assessment in blood, urine and saliva.


Xiulou

Latest:

Simultaneous Determination of Formononetin, Biochanin A, Daidzen and Genistein in Trifolium pratense (Red Clover) by HPLC

A simple rapid HPLC method for simultaneously determiing formononetin, biochanin A, daidzen and genistein in Red Clover


Karen L. Wahl

Latest:

Investigating Solvent Purity Using Comprehensive Gas Chromatography: A Study of Acetones

Investigating Solvent Purity Using Comprehensive Gas Chromatography: A Study of Acetones


Chris Crafts

Latest:

Single Calibrant Approach for the Analysis of Unknowns Using Dual Gradient Pump and Charged Aerosol Detection

Quantification of substances, such as drug impurities or library compounds when pure standards are not available is difficult yet often necessary.


Anil R. Oroskar

Latest:

Continuous Chromatographic Separation of Salt From Sugars by Simulated Moving Bed Technology (SMB) Using Orochem Zucchero Columns

Simulated Moving Bed technology (SMB) is a continuous chromatography technique widely used in the pharmaceutical/biotechnology industry. The continuous chromatographic separation of sodium sulphate (Na2 SO4) from a mixture of glucose and mannose was established by using the Orochem Zuccheroâ„¢ columns and the SMB technology. The main advantages of SMB over batch chromatography includes better yields, higher purity, and decreased solvent usage, which together make the SMB technology economically viable and ideal for desalting applications.


Domingo Gázquez

Latest:

*** TEST *** Estimation of the Main Sources of Uncertainty in Chromatographic Analysis: Determination of Biogenic Amines ***TEST ***

This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines. The authors identify and estimate each source of uncertainty to establish the accuracy of results and to obtain a better understanding of the method. Thus, measurement uncertainty was split into two sections: uncertainty related to the working conditions, which considers the equipment used, and inherent uncertainty, which includes the chemical stages indicated in the procedure as well as calibration sources, taking into account the existence of the matrix effect. Recovery studies also were made to quantify the contribution of bias to the overall uncertainty. This parameter was calculated for the determination of biogenic amines in different types of samples.


Mareike Naguschewski

Latest:

Rapid Determination of DNPH Derivatized Carbonyl Compounds by UHPLC

Carbonyl compounds, in particular aldehydes, are reactive volatile substances. They are of concern to the public, because they are emitted as air pollutants by a large range of industrial processes and other combustion sources.


A.J.R. Heck

Latest:

Enhancing Phosphotyrosine Proteome Coverage Using a Combined ETD and CID Approach on a LTQ Orbitrap XL ETD

Collision-induced dissociation (CID) and electron transfer dissociation (ETD) are complementary mass spectrometric fragmentation techniques. We have used CID and ETD in different approaches to analyse tyrosine phosphorylation using a Thermo Scientific LTQ Orbitrap XL equipped with ETD.


Fraser McLeod

Latest:

Maximizing the Peak Production Rate in Off-line Comprehensive Two-Dimensional Liquid Chromatography with MS Detection

An optimization strategy to obtain the best possible performance in the shortest analysis time for comprehensive off-line 2D-LC.


Pierangela Palma

Latest:

Toward a Universal Detector for Small Molecule Applications: Direct-EI in LC–MS

This article describes the operating principles of the direct-electron ionization (EI) interface, which is becoming more popular in many LC–MS applications. Matrix effects and the role of direct-EI as a universal detector for small molecule analysis are also discussed in detail. The advantages and drawbacks of this approach are described and a comparison with atmospheric pressure ionization (API) interfaces is made. The potential of direct-EI is illustrated with a selection of practical applications.


Erik Spinnel

Latest:

A Modular Approach to Pressurized Liquid Extraction with In-Cell Cleanup

A modification of the popular PLE technique is discussed.


Steffen Wiese

Latest:

Method Development for Fast Separation of Polycyclic Aromatic Hydrocarbons Using Micro-LC - The Importance of the Dwell Volume

This article will shed some light on recent developments of micro-LC and the possibility of applying fast separations while reducing toxic and costly solvent waste.


Rosanne Slingsby

Latest:

Matrix Elimination — In-line Removal of Chloride using InGuard Ag and Na Cartridges

In ion chromatography, the presence of a large amount of matrix ions makes quantification of the target ions difficult. Selective removal of matrix ions - matrix elimination - can be performed by treating a sample with a solid-phase extractant. Halides can be removed by precipitation with silver, which is present as a counterion in a cation-exchange resin. A subsequent treatment with a cation-trapping column removes residual dissolved silver ions.


Claudio Brunelli

Latest:

Analytical Method Lifecycle of SFC Methods from Development Use to Routine QC Implementation; Supporting Small Molecule R&D and Commercialization

In this article, we review some key considerations for chromatographic technique selection and method development across the full drug process.


Bing Li

Latest:

Simultaneous Determination of Formononentin, Biochanin A, Daidzen and Genistein in Trifolium pratense (Red Clover) by HPLC

A simple and rapid HPLC method was established to simultaneously determine the active ingredients of red clover.


Warren Potts

Latest:

Analytical Techniques in Exploring the Persistent Global PFAS Problem

The presence of PFAS in the environment requires governmental agencies to establish regulatory limits for PFAS in human essentials, such as drinking water. LC–MS/MS can be used to analyze a wide range of sample types containing PFAS, but avoiding PFAS contamination is critical for this technique to work effectively.


Constantin S. Sychov

Latest:

The Unique Selectivity of π-Interactions for Solid-Phase Extraction

Hypercrosslinked polystyrene-type (solid-phase extraction) SPE materials exhibit a unique ability to enter p-interactions with aromatic, heterocyclic and unsaturated compounds. This property permits selective extraction and pre-concentration of the above classes of species from non-polar media and fatty matrices. The principle has been exploited for developing analytical protocols to determine polar furan derivatives in mineral transformer oil, polyaromatic hydrocarbons (PAHs) in smoked fish and for the fractionation of polychlorinated aromatic compounds in environmental matrices.