How do non-alkylsilica columns provide us an additional dimension of column selectivity?
The authors descrive the use of GC–MS to isolate and identify potentially toxic compounds in concentrated extracts of sewage treatment plant effluents.
IMS is a valuable tool for biopharmaceutical analysis. Two formats in particular have proven useful: cyclic IMS and structures for lossless manipulations (SLIM).
The authors compare fast LC}MS with a flow injection analysis}MS method for effective quantitation in the high-throughput environment of today's drug discovery laboratories.
LCGC spoke with Elisabeth Bik, PhD, of Harbers Bik LLC about the challenge of preventing scientific and research misconduct in scientific publishing. This segment is Part 6 of 6 and concludes our conversation with Bik.
Glycoprotein monosaccharide compositional analysis is important for the development and manufacture of glycoprotein human therapeutics. Here we report a robust method for this analysis. This chromatographic method requires no mobile phase preparation thus saving time and delivering excellent retention time reproducibility that results in good method reproducibility.
In the early days of dioxin analysis, applied methods were laboratory- and time-consuming. Only GC–HRMS, which is complicated, was used. Nowadays, GC–MS/MS is suitable for control proposes. Using GC–MS/MS means that solvent consumption for sample preparation can be reduced by a factor of 10 and the purity of the obtained fraction can be enhanced, indicating that GC–MS/MS is appropriate for dioxin analysis.
Torion Technologies Inc.
This article establishes the estimation of the uncertainty associated with the chromatographic determination of biogenic amines. The authors identify and estimate each source of uncertainty to establish the accuracy of results and to obtain a better understanding of the method. Thus, measurement uncertainty was split into two sections: uncertainty related to the working conditions, which considers the equipment used, and inherent uncertainty, which includes the chemical stages indicated in the procedure as well as calibration sources, taking into account the existence of the matrix effect. Recovery studies also were made to quantify the contribution of bias to the overall uncertainty. This parameter was calculated for the determination of biogenic amines in different types of samples.
Hyaluronic acid (HA) is a naturally occurring, unbranched polysaccharide that consists of alternately repeating D-glucuronic acid and N-acetylglucosamine units. This biopolymer is present throughout all mammalian systems but occurs primarily in synovial (joint) fluid, vitreous humor, and various loose connective tissues (such as rooster comb) (1). HA is of enormous commercial interest for ophthalmic, medical, pharmacological, and cosmetic applications.
Field-flow fractionation (FFF) coupled to light scattering is a powerful method to separate and characterize nanoparticles, proteins, and polymers from a few nanometres to a few micrometres. The technique is one of the few that can cover the full size range of nanomaterials and provide high-resolution size distributions and additional characterization. New developments in FFF enhance performance and productivity.
A discovery-based, untargeted metabolomics analysis of hundreds of yeast metabolites under robust, controlled extraction conditions followed by identification is described.
An overview of high-throughput process development (HTPD) tools and approaches, as well as a case study
Metabolomics, the study of small molecule metabolites that are found within a biological sample, is an emerging field of study. Progress in this field depends upon technological advancement in the fields of LC–MS and separation technology.
A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
Detection, analysis, and characterization of low-abundant metabolites remain an unresolved problem in metabolic studies. In this study, we report a novel approach to address this challenge. The current methodology is derived from the predictive multiple reaction monitoring (pMRM) mode available on triple-quadrupole linear ion trap mass spectrometry (MS) systems. The pMRM mode offers the highest sensitivity among various acquisition modes for studying trace levels of metabolites of the herbicide clomazone in plants. Additionally, this method allows for the identification of positional isomers of metabolites.
The inclusion of time-resolved selected reaction monitoring (SRM) functionalities into mass spectrometer control software allows large numbers of peptides to be quantified using short LC–MS-MS methods.
This application note describes the method for detection of nanogram levels of explosive constituents in seawater samples (e.g., after detonation of unexploded ordnance devices). The improved chromatographic method was developed using the Agilent 1290 Infinity LC Method Development system.
An efficient method for forensic analysis of amphetamines and synthetic cathinones - the illicit drugs often called "bath salts" - in hair samples.
Some of the newer hydrophilic interaction liquid chromatography (HILIC) columns are reviewed, and experiments performed to categorize columns for optimized separations are described.
Here is a step-by-step approach to investigate the source of ghost peaks in a gradient LC method.
A summary of the most recent advances in sample preparation, instrumentation, and data-processing techniques for MALDI-IMS
Detailed examples of light-scattering techniques are presented as well as how their performance compares to MS and other methods.
The exploration of myxobacterial metabolite profiles by LC–MS screening for the presence of new natural products is described. Extracts from fermentations of Myxococcus strains are analysed by UPLC-coupled ESI-TOF mass spectrometry and the obtained data are processed using principal component analysis (PCA). The generation of molecular formulae from accurate mass measurements facilitates rapid compound identification.
Here's how these new reference standards were characterized.
Nano LC is now widely applied in proteomics, and also is robust enough for application in fields such as pharmaceutical analysis.