GC and TLC methods are demonstrated for quantification of stigmasterol 3-O-β-D-glucopyranoside (S3G), the main active component in the herbal nutraceutical Balanites aegyptiaca, an antihyperglycemic in Egyptian folk medicine.
The efficiencies of microbore-2 columns, which are prepared from blanks that have a wide variety of inner surface roughness, drop sharply when the size of individual surface roughness features approaches the particle size of the packing material. The results suggest that two categories of packed column structure relate to the surface features and yield high and low efficiency columns. This installment of "Column Watch" discusses this conclusion in terms of the stability of an agglomerated layer of packing particles on the blank wall when subjected to shear forces during column packing.
We explore the impact of two different stationary phases and ion-pair reagents on the retention behavior of a therapeutic peptide using reversed-phase liquid chromatography. This information is of fundamental importance for the development of reliable, selective, and fast analytical methods able to separate and identify the target peptide.
A novel LC–MS/MS method, with a dual ESI and APCI source using simple solvent extraction for sample preparation, was validated for analysis of 102 pesticides and 5 mycotoxins regulated by Colorado state in dried hemp.
This paper proposes a new method of flash qualitative identification (FQI) to qualitatively identify a certain target component from a mixture within half a second by disusing the analytical column, which is a time-consuming unit in current chromatography instruments. First, a Noised Spectrum Identification (NSI) model was constructed for the data set generated directly by diode array detector (DAD) without the process in an analytical column. Then, a method called vector error algorithm (VEA) was proposed to generate an error according to the DAD data set for a mixture and a specific spectrum for the target component to be identified. A criterion based on the error generated by the VEA is used to give a judgement of whether the specific spectrum exists in the DAD data set. Several simulations demonstrate the high performance of the FQI method, and an experiment for three known materials was carried out to validate the effectiveness of this method. The results show that the NSI model concurs with the real experiment result; therefore, the error generated by the VEA was an effective criterion to identify a specific component qualitatively, and the FQI method could finish the identification task within half a second.
Reduce sample prep time by filtering your water samples in an auto sampler ready Thomson filter vial. These vials help reduce sample prep time and reduced materials needed.
A validated method was developed for screening short to long chain PFAS in industrial water, using direct injection with no sample preparation.
A new method has been developed to provide a sensitive, accurate and convenient GC–MS method to align with the new European regulation in relation to the introduction of the new Accutrace Plus marker for fuels.
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.
In this paper, two adeno-associated virus (AAV) genome integrity analysis workflows are introduced; a standard sample preparation protocol and an accelerated procedure, both utilizing capillary gel electrophoresis with laser induced fluorescent detection (CGE–LIF) to analyze the released nucleic acids.
The success of screening column and mobile phase combinations that generate dissimilar selectivity is highlighted in a typical method development strategy.
The incorporation of a post-column reaction using a 3D-printed, two-stage microreactor is showing groundbreaking performance improvements for flame ionization detection in many gas chromatography applications—and delivers carbon universal response.
The authors describe a method of reductive chlorination that enables the determination of total PCB content by gas chromatography with flame ionization detection.
There are many benefits of using high-resolution mass spectrometry (HRMS) in analyzing PFAS accumulating in living organisms. This article shows how HRMS, when combined with exposure-relevant mixtures, can help elucidate more about PFAS toxicity and exposure.
High-resolution mass spectrometry (HRMS) is an increasingly critical tool for identifying, characterizing, and monitoring attributes of protein-based therapeutics.
Online SPE–LC–MS/MS combined with the method presented enabled automated cleanup of food extracts and determination of PFAS compounds in the ng/kg range.
The advantages provided by the implementation of ion mobility spectrometry (IMS), and in particular travelling wave ion mobility spectrometry (TWIMS), in traditional liquid chromatography–mass spectrometry (LC–MS) systems are discussed.
The article discusses the classification and characterization of GC×GC column sets based on polarity and orthogonality, introducing a standardized approach using a reference mixture called the Century Mix to evaluate the selectivity and performance of these column sets.
Analysis of the compositional variation in living cells is essential for understanding biological processes. Single-cell elemental analysis by triple-quadrupole ICP-MS is emerging as a selective, highly sensitive, and potentially high-throughput technique for the study of constitutive elements, and uptake of metallodrugs (or metal-containing nanomaterials) in single cells.
As 2D-LC becomes used more widely and in regulated laboratory environments, development and implementation of SSTs will be critical for successful routine use of the 2D-LC technique.
Analyzing representative standard mixtures, APIs, and synthetic impurities shows that when TRLC is combined with RPLC in 2D-LC, separation performance is improved. We explain why.
Non-targeted analysis of small molecules with ambient ionization mass spectrometry (AI-MS) is enabled by new mass spectral libraries and algorithms, such as the inverted library search algorithm (ILSA) developed at NIST.
An overview of different approaches for the qualitative and quantitative analysis of polysorbates.
This GC–FID method enables accurate determination of cooling agents, which are flavor compounds commonly used in cigarette tipping paper.
After 14 years in print, Incognito’s last article takes a look at what has changed over a career in chromatography, but it predominantly focuses on what the future might hold in terms of theory, technology, and working practices.
Two alternative approaches based on gas chromatography coupled to tandem mass spectrometry (GC–MS/MS) were developed to control the maximum residue limit of the banned insecticide, ethylene oxide (EtO), and its transformation product, 2-chloroethanol (2-CE).
An overview of different approaches for the qualitative and quantitative analysis of polysorbates.
Lipids in SFC are mainly separated according to their lipid classes, which simplifies quantification with standards. In this study, SFC coupled with drift time IM‑QTOF-MS was used to characterize the HepG2 lipidome.
Given that sample preparation consumes over two thirds of analysis time, sample preparation becomes the bottleneck issue in analytical chemistry, resulting in the urgent necessity of developing accelerated sample preparation techniques.