The success of screening column and mobile phase combinations that generate dissimilar selectivity is highlighted in a typical method development strategy.
This information is supplementary to the article “Non-aqueous Ion-Exchange Chromatography Using High Acid‑base Concentration: A Strategy for Purifying Non-crystalline Pharmaceutical Intermediates” that was published in the March 2022 issue of LCGC Asia Pacific.
A collaborative multi-analyte method developed utilizes HPLC and UHPLC to analyze more than 70 active ingredients. This method offers a validated approach for determining technical AI alongside linearity, precision, accuracy, and specificity tests for seven active ingredients.
HS-SPME-GC–MS was combined with OPLS-DA data analysis to tentatively identify eight chemical markers to differentiate the geographical origins of cigar leaf samples.
Pepsin digestion and guanidine hydrochloride post-digestion can improve sequence coverage in antibody peptide mapping compared with trypsin digestion.
The latest developments and challenges of using liquid chromatography (LC) for copolymer analysis are discussed.
The UHPLC–MS/MS method can accurately determine the presence of these illegal feed additives in swine tissues.
The current challenges and future perspectives of the purification of cannabinoids from cannabis extracts are presented in this review article.
The challenges that arise during cannabis metabolomics analysis using ultrahigh-performance reversed-phase liquid chromatography coupled with high-resolution tandem mass spectrometry (UHPLC–reversed-phase–HRMS/MS) are presented.
Compact instrumentation offers important advantages for many workflows, as illustrated by these examples.
By calculating optimal stationary-phase composition and physical parameters, column developers can construct columns that provide the exact separation requirements desired by analysis or current methods.
The authors demonstrate a new detection method for various anions of weak acids separated by ion chromatography and point out the main advantages of this method.
The basic operating principles of ion mobility spectrometers (IMS), their resulting strengths and weaknesses, and why both perfectly align with the capabilities and requirements of gas chromatographs are discussed.
U.S. Environmental Protection Agency (EPA) Method 1633 signifies a pivotal shift in per- and polyfluoroalkyl substance (PFAS) determination, extending beyond drinking water.
Measuring volatile phenols in wine is essential in ensuring superior wine quality. A new analytical technique, called solid-phase mesh-enhanced sorption from headspace (SPMESH), was modified with direct immersion (DI) conditions and coupled to direct analysis in real time–mass spectrometry (DART–MS) to be used to detect smoke taint in winemaking.
By calculating optimal stationary-phase composition and physical parameters, column developers can construct columns that provide the exact separation requirements desired by analysis or current methods.
In the present study, a gradient reversed-phase high-performance liquid chromatography (RP-HPLC) method has been designed and validated to quantify ornidazole (OZ) in the marketed formulation (oral gel) with the application of QbD.
The authors explore computer-aided workflows and machine learning, aimed at optimizing LC parameters, focusing on kinetic and thermodynamic aspects, and proposes closed-loop optimization strategies.
Selected ion flow tube mas spectrometry (SIFT–MS) offers real-time measurements directly from air without chromatography or sample preparation, providing an attractive alternative for these hard-to-measure volatile organic compounds.
Matrix interferences can impact routine analysis with triple quadrupole methods for monitoring and quantifying PFAS in food.
Quantification of Tau proteoforms in cerebrospinal fluid (CSF) could be useful to diagnose neurodegenerative diseases. LC–MS/MS results can help explain the underlying molecular mechanisms of disease evolution.
During the past five years, many manufacturers of HPLC columns have focused on improving stationary phase stability and reproducibility. In this study, the authors use a variety of test solutes to compare the efficiency, selectivity, and hydrophobic retention mechanisms of five commercially available HPLC columns based silica, alumina, zirconia, and polystyrene cross-linked with divinylbenzene as the support.
HPLC coupled with negative ESI-MS provides a reliable method with unique capabilities for separation and identification of (therapeutic) oligonucleotides.
An improved method for determining total galactooligosaccharide (GOS) content in food and supplements using high performance anion exchange chromatography with pulsed amperometric detection is described.
Size-exclusion chromatography (SEC), with the use of ammonium acetate buffer, can be coupled on-line to electrospray ionization MS for the characterization of size variants of therapeutic monoclonal antibodies (mAbs). A quadrupole time-of-flight (QTOF) MS system was employed, and the MS method was optimized to achieve favorable sensitivity for high-mass detection, while maintaining the structural integrity of the aggregates (or high molecular weight species) and fragments (or low molecular weight species).
Two-dimensional liquid chromatography (2D-LC) allows much greater resolution of peaks than is possible in a classical single dimensional separation. For the next development in separations, we employed 2D-LC in two highly orthogonal dimensions of separation with four mass spectrometers for detection, with parallel detection in each dimension. We have further broken ground by using three dimensions of separation with four mass spectrometers, using two parallel second dimensions.
Successful GC analysis requires careful control of carrier gas. Here, we explain how to measure and control flow rate, use constant pressure vs. constant flow, and more.
Quantification of European Union (EU)-priority polycyclic aromatic hydrocarbons (PAHs) in plant matrices is a crucial task. Various methods for enrichment and preconcentration, such as the preloaded-pipette tip solid‑phase extraction (SPE) (1), are available. Nevertheless, analyte recovery as a result of homogenization, sample preparation, and extraction are rarely discussed in the field of phytopharmacy. This study deals with the recovery in dry plant extracts, which are typically used in phytopharmaceuticals and reflect the actual polycyclic aromatic hydrocarbon content in the commercially available end product (2). The aim of this study was to monitor benzo[a]pyrene, benzo[a]anthracene, chrysene, and benzo[b]fluoranthene loss of spiked samples as a result of commonly-used sample pretreatment, extraction, filtering, and evaporating techniques in 1:1 (v/v) cyclohexane–ethyl acetate primulae flos and sambuci flos dry extracts. Results showed that improper sample preparation can lead to false results. In the case of benzo[a]pyrene with a deviation of 155% from the theoretical true value.