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.
Strategies to screen and develop a preparative HPLC method and its up-scaling for purification of CBD from Cannabis extract
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.
How is mD-LC–MS changing the way we evaluate HPLC peaks and assess performance?
How to speed up sample prep time and equivalent acccuracy and precision.