Author


Ayako Nomura

Latest:

An Ultrahigh-Performance Liquid Chromatography Alternative to Animal Testing for Skin Sensitization

OECD-compliant amino acid derivative assay (ADRA) testing and method transfer to UHPLC conditions is presented.


Charles Johnson

Latest:

Novel LC–MS/MS Method with a Dual ESI and APCI Ion Source for Analysis of California-Regulated Pesticides and Mycotoxins in Medium-Chain Triglyceride (MCT) Oil Cannabis Tinctures

A novel liquid chromatography–tandem mass spectrometry (LC–MS/MS) method with a dual electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) source was developed for analysis of 66 pesticides and 5 mycotoxins regulated by the State of California in medium-chain triglyceride (MCT) oil cannabis tinctures. The limits of quantitation (LOQs) of all of the pesticides and mycotoxins were well below California state action limits of these analytes in cannabis-based non-inhalable or edible products. A total of 62 (out of 66) pesticides and 5 mycotoxins were analyzed using LC–MS/MS with an ESI source, and the remaining 4 pesticides were determined using LC–MS/MS with an APCI source. A simple, fast, and cheap acetonitrile solvent extraction method was used for sample preparation to get good recovery and achieve high throughput for this analysis. For late-eluted analytes, a number of internal standards were used to compensate for ion suppression effects from the hydrophobic matrix.


Chao Chen

Latest:

Acid-Catalyzed Isomerization of Carbonyls-2,4- dinitrophenylhydrazone in Mainstream Smoke of Heat-Not-Burn Tobacco Product for HPLC Analysis

Errors arising from the DNPH approach commonly used to analyze carbonyl compounds in smoke from heat-not-burn (HNB) tobacco can be avoided by using the approach described in this study.


William Trompeter

Latest:

Ion-Exchange Displacement Chromatography: Scale-Up and Displacer Clearance for Recombinant Human Brain-Derived Neurotrophic Factor

Displacement chromatography is a viable alternative to elution chromatography, but the biotechnology industry has yet to fully exploit this technique. The authors present results of a pilot-scale ion-exchange displacement process developed for the removal of variants from recombitant human brain-derived neutrotrophic factor.


Troy T. Handlovic

Latest:

Next Generation Peak Fitting for Separations

Separation scientists frequently encounter critical pairs that are difficult to separate in a complex mixture. To save time and expensive solvents, an effective alternative to conventional screening protocols or mathematical peak width reduction is called iterative curve fitting.


Caden Gunnarson

Latest:

But Why Doesn’t It Get Better? Kinetic Plots for Liquid Chromatography, Part 3: Pulling It All Together

The impact of extracolumn dispersion on kinetic plot curves is investigated. A web-based calculator that allows users to make their own kinetic plots with examples of how the tool can be used to troubleshoot underperforming columns and support column selection is discussed.


Saban Oezipek

Latest:

The Power of Trypsin Immobilized Enzyme Reactors (IMERs) Deployed in Online MDLC–MS Applications

Commercially available trypsin IMERs can digest proteins with high sequence coverage and robustness, facilitating online multidimensional LC–MS.


Vincent Diederich

Latest:

Efficient Sample Preparation and High-Capacity Columns for Successful Food and Beverage Analysis

Overcoming the challenges of food and beverage analysis with ion chromatography (IC).


Katie Comstock

Latest:

Extractable and Leachable Testing for Pharmaceutical Packaging, Finished Pharmaceutical Products, and Medical Devices: An Analytical Perspective

Extractable and leachable (E&L) testing for finished pharmaceutical products, bioprocess manufacturing systems, and medical devices is currently a subject of intense interest. The majority of the challenges encountered in analytical workflows are related to the highly complex matrices and relatively low analyte evaluation thresholds seen in E&L studies. This paper provide options for executing E&L testing to supporting regulatory submissions. There are multiple compliant routes possible, and the presented workflows and analytical solutions are only one of multiple successful approaches.


John Schmitz

Latest:

Quantitative Analysis of PFAS in Milk, Infant Formula, and Related Ingredients Using LC–MS

This method for PFAS analysis in milk and infant formula is robust, reliable, and reproducible, with scope to expand the list of PFAS in the future.


Chiew Mei Chong

Latest:

Fully Automated QuEChERS Extraction and Cleanup of Organophosphate Pesticides in Orange Juice

A fully automated quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and extract clean-up method is described for analysis of organophosphate pesticides in orange juice. This method uses GC–MS and LC–MS along with an industry standard robotic x,y,z-sampling system.


Ann Marie Rojahn

Latest:

A Study on the Optimization of the Ion-Pair Reversed Phase Liquid Chromatography Analysis of Protected And Unprotected DNA Oligonucleotides

This article describes a comprehensive study on optimizing ion-pair reversed-phase liquid chromatography for analysing protected and unprotected single-stranded DNA oligonucleotides.


Han Chen

Latest:

Sample Preparation by Electric Field–Assisted Extraction

Integrating electric fields into extraction techniques increases sensitivity and selectivity. These approaches are compatible with miniaturized, portable, and many biological samples.


Alois Jungbauer

Latest:

Monoliths as Stationary Phases for Separating Biopolymers – Fourth-Generation Chromatography Sorbents

Monoliths are chromatography sorbents cast into columns as a single continuous piece in contrast with regular chromatographic sorbents, which are packed as individual particles. The guest authors compare three such novel sorbents with a conventional particle-packed column.


Sina Hoelterhoff

Latest:

The Power of Trypsin Immobilized Enzyme Reactors (IMERs) Deployed in Online MDLC–MS Applications

Commercially available trypsin IMERs can digest proteins with high sequence coverage and robustness, facilitating online multidimensional LC–MS.


Separation Science

Latest:

The State of the Art in Life Science Analysis; Virtual Symposium

Webinar Date/Time: Wednesday, October 18th, 2023 12:30 pm BST 7:30 am EDT 13:30 pm CEST Thursday, October 19th, 2023 12:30pm BST | 7:30am EDT | 13:30pm CEST


Reginald F. Cross

Latest:

Reducing Sample Size and Obtaining Representative Samples

Guest author Reg Cross discusses strategies for collecting samples from large masses of material. He also describes the problems associated with acquiring truly representative samples for analysis.


Ke Huang

Latest:

Optimization of Determination Method of Cooling Agents in Cigarette Tipping Paper by Gas Chromatography

This GC–FID method enables accurate determination of cooling agents, which are flavor compounds commonly used in cigarette tipping paper.


Ana-Maria Albu

Latest:

Characterization of Styrene–Butadiene Block Copolymers by Gel Permeation Chromatography

The authors compare their results in analyzing styrene–butadiene block copolymers by gel permeation chromatography with other methods, such as Fourier transform infrared spectroscopy and pyrolysis gas chromatography.


Hall Analytical

Latest:

The Ever-Changing World of Extractables and Leachables: Lessons learned and future challenges

October 4, 2021 at 3pm BST | 10am EST | 4pm CEST Join global industry and regulatory experts as they discuss current hot topics in extractables and leachables (E&L) testing for pharmaceuticals, biopharmaceuticals and medical devices.


Melissa Sherman

Latest:

Six Key Differentiators Between Liquid Chromatography and High-Resolution Ion Mobility

Using ion mobility, analytes that have the same molecular mass can be separated by their shape, centers of mass, and collision cross section, but challenges such as ion loss can still occur. A new development in ion mobility separation, high-resolution ion mobility (HRIM), addresses such problems, and is particularly well suited to challenging applications, such as glycosylation monitoring of biological drugs and vitamin D analysis.


Marise van der Vegt

Latest:

Dispersive Solid-Phase Extraction and Solid-Phase Extraction for ppt-level PFAS Analysis in Apples: A Comparison

Per- and polyfluoralkyl substances (PFAS) are found in our food. Sensitive, precise, and accurate analytical methods are needed to estimate human exposure to these chemicals. A comparative study was performed between two extraction and cleanup methods (solid-phase extraction [SPE] and dispersive SPE) for the analysis of PFAS in apples. Both methods showed excellent sensitivity, precision, and accuracy. dSPE has some benefits over conventional SPE, and vice versa. The advantages and disadvantages of both methods are discussed.


Jordy J. Hsiao

Latest:

Systematic Evaluation of HILIC Stationary Phases for MS Characterization of Oligonucleotides

Hydrophilic interaction chromatography–mass spectrometry (HILIC-MS) offers a flexible and efficient alternative to ion-pairing reversed-phase liquid chromatography (IP-RPLC) for oligonucleotide analysis, with column selectivity and mobile phase pH being key factors in optimizing retention and detection.


Irene Suarez Marina

Latest:

Analysis of siRNA with Denaturing and Non-Denaturing Ion-Pair Reversed-Phase Liquid Chromatography Methods

A column with chemically modified column hardware showed improvements in analytical performance for siRNA compared to a conventional stainless-steel column.


Kelly Wormwood Moser

Latest:

Effectiveness of High-Resolution Ion Mobility for Complex Analyses

HRIM has emerged as a robust separation strategy for complex chemical analyses due to its ability to improve peak capacity and aid in the separation of isobaric signals.


William Robberson

Latest:

Identification of Microplastics in Environmental Monitoring Using Pyrolysis–GC–MS Analysis

Pyrolysis–gas chromatography–mass spectrometry has advantages for the analysis of environmental microplastic samples compared to other leading analytical methods, including spectroscopic techniques.


Hepeng Ni

Latest:

Optimization of Determination Method of Cooling Agents in Cigarette Tipping Paper by Gas Chromatography

This GC–FID method enables accurate determination of cooling agents, which are flavor compounds commonly used in cigarette tipping paper.


Sebastiano Pantò

Latest:

Comprehensive Gas Chromatography Coupled to Simultaneous Dual Detection (TOF-MS/FID) as a Confirmatory Method for MOSH and MOAH Determination in Food

Food contamination from mineral oil saturated hydrocarbons (MOSHs) and mineral oil aromatic hydrocarbons (MOAHs) is problematic and requires a sensitive analytical technique. These contaminants were analyzed using GC×GC with flame ionization detection (FID) and time-of-flight–MS (TOF–MS) parallel dual detection. The method provides enhanced chromatographic separation, along with the full mass spectra information, and overcomes difficult interferences, resulting in reduction of false positives over conventional GC–MS methods.


Bingquan Chang

Latest:

Evaluating Two Dioscin-Based Silica Stationary Phases and their Application to Achiral and Chiral Separations

Improved analysis of pharmaceutical and natural medicine products requires advances in reversed-phase LC stationary phases. We examine two synthesized stationary phases with applicability in quality control and chiral separation for analysis of natural products.


Alessandro Buratti

Latest:

Purification and Isolation of Cannabinoids: Current Challenges and Perspectives

The current challenges and future perspectives of the purification of cannabinoids from cannabis extracts are presented in this review article.