Application Notes

Scientists employ fused silica capillary tubing routinely in a wide range of analytical applications, encompassing GC, CE, capillary LC, and CEC. It has proven as an ideal substrate for interfacing in hyphenated techniques.

Complete separation of critical pain management drug analytes from hydrophilic matrix components and isobaric interferences was achieved using the new Raptor™ SPP Biphenyl LC column in less than 5 min

Avermectins are a series of 16-membered macrocyclic lactone derivatives that are used extensively in animal and crop protection

enable authentication of Si-Wu-Tang, a separate comprehensive 2D-LC analysis of each herb contained in Si-Wu-Tang was performed.

This application utilizes the original, non-buffered QuEChERS (acronym for quick, easy, cheap, effective, rugged, and safe) technique to quantify anabolic steroids in human whole blood

Polar neurotransmitters are difficult to retain using ODS columns. In this work we show two different methods to retain these polar analytes on the multi-mode Scherzo SS-C18 column. The versatility in retention characteristics with simple changes in mobile phase is highlighted.

A rapid, accurate, and reproducible method was developed for high-throughput testing of nicotine, cotinine, trans-3’-hydroxycotinine, nornicotine, norcotinine, and anabasine in urine. Data show that a fast and highly efficient analysis of these basic compounds can be achieved with the Raptor Biphenyl column using standard reversed-phase LC–MS mobile phases that are compatible with a variety of LC–MS instrumentation.

Disinfection by-products (DBP) are an ever-present nuisance in the efforts to purify drinking water, wastewater, and municipal waters from various sources. An emerging class of DBP compounds with health effects is nitrosamines which result from chloramination or chlorination if the water is nitrogen-rich. Five of these nitrosamines have been listed on the US EPA’s new Contaminant Candidate List (CCL-3). Of the nitrosamines, the most common and problematic is N-nitrosdimethylamine (NDMA). The maximum admissible levels set by the US EPA are 7 ng/L for NDMA and 2 ng/L for N-nitrosodiethylamine (NDEA).

Generally speaking, chromate - Cr(VI) - is classified as allergenic, carcinogenic, and extremely toxic and is subject to strict monitoring. Cr(VI) can occur in various concentrations in different areas, for example, drinking water, toys, or textile and leather products. Metrohm has developed ion chromatographic determination methods for determining Cr(VI) in various concentration ranges (ng/L to mg/L) with inline sample preparation techniques for various matrices. The method can be almost entirely automated. In the following application note, we present the analysis of hexavalent chromium in toys, leather, and drinking water.

Rigorous conditioning of sorbent tubes is an essential part of any sampling and analysis protocol. This application note will explore the cost savings and productivity enhancements that can be made by off-line conditioning, rather than on‑line with the thermal desorber itself. In particular, we will focus on the revenue resulting from running more analytical samples, the cost-effectiveness of increasing sample capacity by this approach, and the benefits that stem from using nitrogen rather than helium.

Used extensively from the 1940s through the 1960s, organochlorine pesticides are chlorinated hydrocarbons used in agriculture and mosquito control. The organochlorine pesticides accumulate in the environment, presenting an ongoing issue with adsorption and accumulation in the population as a result of ingestion.

Membrane proteins - together with lipids - make up biological membranes that are essential for life. In order to understand the role of membrane proteins in assisting membranes to carry out many different functions, it is of great importance to understand the structure of those proteins.

Glycosylation is one of the most common forms of post-translational modification of proteins. The polysaccharide side chains (glycans) play critical roles in physiological and pathological reactions. Besides the interest in characterizing glycosylation pattern of proteins for structure/function analysis, the thorough characterization of glycosylation is also a major quality parameter in the production of biotherapeutics. Hydrophilic interaction liquid chromatography (HILIC) is a well-recognized technique that effectively separates and quantifies isolated glycans.

Heparin is a polydisperse, heterogeneous polysaccharide derived from animal tissue. Heparin has been used as an anticoagulant for over 60 years and one of the fundamental parameters for characterizing unfractionated heparin (UFH) is its molecular weight (MW) and MW distribution. The molecular weight of heparin ranges from 3 to 50 kDa, but, typically falls within the 10 to 20 kDa range for unfractionated heparins used in medical applications. In light of heparin contamination issues in 2008, USP has proposed to include heparin molecular weight determination for the stage 3 heparin monograph revisions.

Most proteins, particularly soluble and membrane-bound proteins expressed in the endoplasmic reticulum, are glycosylated. The extent and result of glycosylation varies.

Organochlorine (OC) pesticides are hydrocarbons with multiple chlorine substitutions primarily used as insecticides. OC pesticides do not break down easily as the chlorine-carbon bonds are very strong.

Supercritical fluid chromatography (SFC) is an evolutionary technology and a powerful tool for enantiomer separation when used in combination with chiral stationary phases (CSPs).

This method increases sensitivity and reduces data acquisition time for a subset of pharmaceuticals and personal care products from the original EPA Method 1694 specifications.

This application note demonstrates the comprehensive 2D-LC analysis of different types of beer. Nontargeted, multisample analysis (fingerprinting analysis) enabled a classification of the different types of beer analyzed.

Due to the highly polar nature of saccharides, the analysis of sugars is typically achieved using hydrophilic interaction chromatography (HILIC).

Organic arsenic compounds added to feed stocks of chicken and poultry pose serious environmental and ecological threats. National and worldwide health organizations, such as the United States Environmental Protection Agency and the US Food and Drug Administration, have recently implemented more stringent concentration limits for arsenic species in drinking water and foodstuffs.

The global demand for fish as a natural source of fresh animal protein, essential fats, minerals, and vitamins continues to rise with the human population.

In brewing, barley undergoes a malting process, the grain if first drenched to make it germinate and then dried in kilns to capture the sugar and flavor compounds for the brewing process.

Pain management LC analyses can be difficult to optimize due to the limited selectivity of C18 and phenyl-hexyl phases.

The physical properties and behavior of polymers depends strongly on the properties of the polymer molecules themselves

Poly(lactic-co-glycolic acid) (PLGA) is a copolymer based on glycolic acid and lactic acid. The two monomer units are linked together by ester linkages and form linear polyester chains

CAPCELL CORE ADME S2.7 (ADME) is a column packed with a novel stationary phase of superficially porous silica (core shell particle) modified by adamantyl functional groups.

The challenging retention of polar organic acids in reversed phase conditions is accomplished using a unique multi-mode stationary phase.

Reflectron lenses are used in time-of-flight (TOF) mass spectrometers to create an electrostatic field to alter ion flow, providing for a longer flight path and therefore greater resolution.

The Intrada Amino Acid column has been shown to be a viable solution for the analysis of amino acids by LC–MS without derivatization.