HPLC and GC Articles

Prion diseases, also known as transmissible spongiform encephalopathies (TSEs), are a unique group of neurodegenerative diseases of the central nervous system, which include bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep, chronic wasting disease (CWD) in deer, and Creutzfeldt–Jacob disease (CJD) in humans.

This issue completes the multi-part MS primer with a list of terms derived from common usage throughout various industries and, while included with the MS Primer. is intended to stand alone. A number of current books recognize the need to monitor and modify the language we use within LC–MS.

Over the last few decades there has been tremendous advancement in the field of sample preparation methods, going hand in hand with the developments of state-of-the-art analytical instruments (1–3).

Asymmetric flow field flow fractionation is a type of field flow fractionation (FFF) separation technique. FFF has been coexisting with size exclusion chromatography (SEC) for several decades.

Part I of this article described the application of Quality-by-Design (QbD) principles to the task of screening analytical columns.

After analytes transit the inlet system and separate in the column, a detector transduces the contents of the exiting mobile phase from a variable chemical signal into an electrical signal that can be recorded and processed to yield qualitative and quantitative information about the analyzed mixture.

Because proteins are polyions with both hydrophobic and hydrophilic surfaces in distinct spatial arrangements, each protein presents unique purification challenges.

LCGC Europe published a paper in 2003 that sought to establish a nomenclature for comprehensive two-dimensional gas chromatography (GC×GC).1 Recently a term called modulation ratio (MR) was added to the lexicon of GC×GC. This defines the way a peak is sampled from a first dimension column into a second column.

Many gas chromatographers are considering hydrogen carrier gas instead of helium or nitrogen, but they might hesitate to do so because they have questions about performance, safety, or cost. This month's "GC Connections" focuses on these and other issues related to hydrogen in the gas chromatography laboratory.

Performance