Author


Jim Bradow

Latest:

Approaches to Singleton Achiral Purification of Difficult Samples for Discovery Research Support

Several approaches for purifying difficult samples more efficiently for discovery research support are mentioned in this paper. These approaches use mass triggered HPLC on various specialty columns.


Yasuo Igarashi

Latest:

CAPCELL PAK C18 MG III, Polymer-coated C18 Stationary Phase, Designed for High-Sensitivity analyses in LC–MS

The SHISEIDO CAPCELL PAK C18 MGIII is an HPLC column packed with a silicone polymer-coated phase, providing excellent peak profiles for basic compounds under acidic conditions, and generating ultimately minimized column bleeding in LC–MS.


Nizar Haddad

Latest:

Sulfated β-Cyclodextrin as Chiral Mobile Phase Additive for Ultrahigh-Pressure Liquid Chromatography

A fast enantiomeric separation of a chiral aromatic amine was achieved, using ultra high pressure liquid chromatography and highly sulfated β-cyclodextrin (S-β-CD) as a chiral additive in the mobile phase. The stationary phase consisted of a core shell support with a particle size of 2.7 µm. Under these conditions the baseline separation was obtained within 2.5 min. The influence of the concentration of the additive, along with the thermodynamics of the separation, were studied. Molecular mechanics calculations were consistent with the experimental data for the order of elution, providing further evidence of these interactions. The enantiomeric separation at high temperature (90 °C) using only water as mobile phase also was achieved for the first time.


Haibo Wang

Latest:

Determination of Volatile Organic Compounds in Water by In-Tube Extraction and Gas Chromatography with Ion-Trap Mass Spectrometry

Over the last 10 years, several solvent-free microextraction techniques for gas chromatography (GC) and mass spectrometry (MS) have been developed. Two of these techniques, solid-phase microextraction (SPME) and stir-bar sorptive extraction (SBSE), are available commercially for the analysis of volatile compounds, such as flavors in foods and beverages, and toxic organic compounds in environmental applications. Other techniques, such as open tubular trapping, inside needle capillary adsorption trap (1), in-tube SPME, capillary microextraction, needle trap, and headspace solid-phase dynamic extraction (2), were also developed for different applications. The basic principle for all of these techniques is essentially the same. Volatile and semivolatile compounds are adsorbed on a sorbent coating, often packed on the interior surface of a capillary column or stainless steel needle. After the sample is concentrated on the coating, the compounds are desorbed thermally in the heated injection port of a gas..


Weiguo Zhang

Latest:

Fast Multi-Residue Pesticide Analysis Using Triple Quadrupole GC–MS-MS

H-SRM provides excellent selectivity for accurate identification and quantification of pesticides in matrix, demonstrating high productivity for effective control at international maximum residue levels (MRLs).


Yuichi Fusho

Latest:

Analysis of Hydrophilic Molecules in Biological Fluid with Novel Mixed-Mode Column

In pharmaceutical development, it is important to analyze small molecules or their metabolites in biological fluids. For this purpose, the analytical methods such as sample pretreatment, 2D-LC and LC–MS have been developed. However there are still problems of resolution and protein adsorption. As a result, satisfying analytical results have not always been achieved.


Patrick M. Jeanville

Latest:

Comparing Scientific Marketing to Analytical Reality

Consumer marketing approaches are creeping into the marketing of scientific instruments. With a careful approach, you can cut through the hype.


Fengmei Zheng

Latest:

Use of Orthogonal Methods During Pharmaceutical Development: Case Studies

The primary goal of early phase development is to gain a fundamental knowledge of the chemistry of drug substances and drug products to facilitate optimization of synthetic schemes and drug product formulations. At the same time, methods are required for release and stability studies to support clinical trials. Ultimately, the knowledge gained during early development translates into designing control methods for commercial supplies. Our approach to meeting this challenge is based upon the use of a primary method along with orthogonal methods. This paper will discuss the overall strategy, with an emphasis on the chromatographic conditions selected to provide systematic othogonality for a broad range of drugs. Case studies will be presented to demonstrate the utility of orthogonal methods to resolve issues that could not have been addressed using a single release and stability method.


Dipankar Ghosh

Latest:

Quantitative Comparison of Hormones in Drinking Water Between Low and High Resolution Mass Spectrometry

The quantitative performance of the latest generation of high-resolution instruments is comparable to that of a triple quadrupole MS, even though different scanning modes are used. Higher-resolution instrumentation also allows flexibility concerning compound identification because the experiment can be set up for targeted quantitation, screening, or both. In an Orbitrap-based instrument, the parallel reaction monitoring (PRM) mode performs most closely to a triple quadrupole mass analyzer using selected reaction monitoring (SRM) mode. This study looks at the performance of an Orbitrap-based LC–MS method for EPA Method 539.


Joseph Turpin

Latest:

A Quality-by-Design Methodology for Rapid LC Method Development, Part III

The guest columnists continue their examination of how statistically rigorous QbD principles can be put into practice.


Claude Mallet

Latest:

Get More Separation Power With Multidimensional Chromatography

Multidimensional chromatography, or comprehensive chromatography, is a well-established technique for the analysis of complex mixtures. However, the technique is often perceived as highly complex and difficult to put into practice for routine applications. Nonetheless, the technique provides exceptional potential for addressing challenging separations. The addition of a dilution factor allows multidimensional chromatography to provide a high level of flexibility and selectivity. The dilution effect is achieved by using a column chemistry format compatible with large flow rates, which now offers the option of large volume injection without volume or mass overload issues. This novel solution can reduce or eliminate the need to add a solvent exchange step, such as evaporation or reconstitution, which significantly reduces the most time-consuming part of the sample preparation process.



T. Fahrenholz

Latest:

Evaluation of Extraction Methods and Bias Correction by EPA Method 6800 Protocol for Mercury Species in Tuna Fish Tissue Using an Ion Chromatograph Coupled to an ICP–MS

Mercury pollution mainly originates from industrial activities such as chlorine production, garbage incineration and above all coal-fueled power generation. The US Environmental Protection Agency (US EPA) considers mercury as highly toxic with a pronounced accumulative and persistent character.


André Villemaire

Latest:

Chemical Warfare Agent Spectral Imaging for Real-Time Identification and Localization

In this article, the authors discuss the need for protection against chemical attacks and the role of passive imaging spectroradiometers in the detection of remote chemical agents.


Dmitri V. Mavrodi

Latest:

Extraction and Detection of Antibiotics in the Rhizosphere Metabolome

Root diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.





Imran Ali

Latest:

Fast Analysis of Third-Generation Cephalosporins in Human Plasma by SPE and HPLC Methods

A fast, selective, and reproducible high performance liquid chromatography (HPLC) method was developed and validated for the analyses of third-generation cephalosporin antibiotics, namely, ceftriaxone, cefixime, and cefdinir in human plasma. The analysis was carried out on a 150 mm Ã- 4.6 mm, 5.0-µm C18 column. The mobile phase used was 80:20 (v/v) 50 mmM phosphate buffer (pH 5.0)–methanol at a flow rate of 1.0 mL/min with 230-nm UV detection.


Jakob Schurek

Latest:

Analysis of Deoxynivalenol in Beer

Mycotoxins, toxic secondary metabolites of several fungal species, represent food safety issues of high concern. Deoxynivalenol, the most abundant trichothecene mycotoxin, can be found worldwide as a contaminant of wheat, barley, maize and other cereals (1,2). The transmission of deoxynivalenol from barley into beer has been reported in several studies (3,4). Therefore, its levels should be controlled.


Takuji Nabetani

Latest:

Posttranslational Modification Characterization via Electron Capture Dissociation Using a Linear Ion Trap Time-of-Flight Mass Spectrometer

Successful characterization of protein posttranslational modifications (PTMs) is critical to our understanding of many biological processes. Unfortunately, attempts to describe PTMs often prove experimentally difficult and result in ambiguous conclusions. As technologies in the field of mass spectrometry (MS) continue to improve, people are turning increasingly to mass spectral techniques for PTM characterization. Recently, novel modes of peptide fragmentation have emerged that are giving scientists greater ability to elucidate protein posttranslational modification. One example is electron-capture dissociation (ECD), an alternative fragmentation mechanism for use in peptide analysis via tandem mass spectrometry. ECD selectively cleaves N-Cα bonds of the peptide backbone, yielding c- and z-ions without the loss of labile PTMs. ECD therefore holds advantages over conventional fragmentation techniques such as collisionally induced dissociation (CID), which often cleave PTMs from the peptide backbone,..



Kikuo Sasamoto

Latest:

Optimizing Flavour Analysis Using Modern Heart-Cutting MDGC

This review discusses recent technological advances in classical heart-cuttting two-dimensional gas chromatography (GC–GC). These developments are then illustrated by application to analysis of important flavour compounds at trace levels in very complex matrices


Orochem Technologies Inc.

Latest:

Orochem Technologies Inc.

High Throughput Sample Preparation Method for Drugs of Abuse in Urine


Christopher R. Bowerbank

Latest:

Rapid Field Detection of Chemical Warfare Agents, Simulants, By-Products, and Precursors Using Solid Phase Microextraction and Portable GC-TMS

Rapid sample preparation using the CUSTODIONâ„¢ solid phase microextraction (SPME) syringe was applied to chemical warfare agents (CWAs), CWA simulants, by-products, and precursors. The samples were analyzed quickly and reliably with a sample-to-sample cycle time of less than 3 min using the GUARDIONâ„¢-7 portable capillary gas chromatograph toroidal ion trap mass spectrometer (GC–TMS).



Peter Ridgway

Latest:

A Case Study of Using Thar SFC-MS Prep 30® to Purify Polar, Basic Pharmaceutical Relevant Compounds

In the past decade, supercritical fluid chromatography (SFC) has experienced a striking resurgence and exponential growth in acceptance, particularly in pharmaceutical and chemical laboratories. In SFC, "supercritical" CO2, in combination with one or more polar organic solvents, most commonly alcohols, are used as mobile phase. The polarity of CO2 is similar to that of hexane, and thereby making SFC a normal phase chromatographic technique. SFC has readily lent itself as an attractive complement to reversed phase HPLC (RPLC). For instance, in separating polar compounds that have little retention, and/or selectivity, even with special polar group embedded columns, SFC holds a unique advantage over RPLC due to its normal phase separation mechanism.


Monika M. Kansal

Latest:

Increasing LC–MS–MS Sensitivity with Luna HILIC

The analysis of polar compounds in support of clinical and preclinical pharmacokinetic studies requires an analytical methodology capable of achieving ultra-low detection and quantification limits. The high sensitivity afforded by coupling HPLC with tandem mass spectrometry (MS–MS) has made it the technique of choice in this environment, but it is subject to the following limitations when reversed-phase liquid chromatography (RPLC) is used


Andrew Marston

Latest:

Modern Countercurrent Chromatography

CCC is an excellent alternative to avoid the problems associated with solid-phase adsorbents, which include irreversible adsorption of sample and the need to replace expensive columns. As a result, CCC is gaining popularity as a purification tool.


Duane Sword

Latest:

Portable FT-IR and Raman Spectroscopy for Explosives Identification

This article discusses instruments that can be used in the field to rapidly and accurately identify various explosives and their precursors.