The Application Notebook-06-01-2011

June 01, 2011

Hydrophilic interaction chromatography (HILIC) has become a popularly used separation mode for carbohydrate HPLC method. There are wide variations in HILIC stationary phase.

June 01, 2011

As the number of chiral columns and chiral separations has grown, it has become difficult to organize the information for use in developing new methods. The success of chiral method development depends on the introduction of appropriate columns. The RegisPack? polysaccharide-based chiral stationary phase (CSP) is most successful in achieving a majority of chiral separations. However, there are cases in which this proven chiral selector leads to partial or no separation. Excellent separations using the newly introduced RegisPack? CLA-1 CSP have been obtained for a range of compounds, either by improving or complementing RegisPack's selectivity.

June 01, 2011

Hydroxyethylstarches (HES) are used increasingly as plasma expanders in medical applications. The HES's circulation time in the blood depends strongly on its molar mass distributions.

June 01, 2011

Aggregated singletons for automated purification (ASAP) is a purification workflow that provides singleton sample purification, registration, and delivery to the materials management department as 30 mM dimethyl sulfoxide solutions for biological screening.

June 01, 2011

Determination of pharmaceuticals in biological matrices is commonly employed in ADME (DMPK), clinical, and forensic analysis. The main techniques used for drug monitoring and analysis are immunoassays, LC, and GC methods.

June 01, 2011

The Food Safety Modernization Act, which was recently signed into law, is the country's first major food legislation since 1938, and increases the FDA's authority over the U.S. food supply. These new regulations require that foods, including baby food, be tested for pesticide residues.

June 01, 2011

Polyolefin (PO) is the largest volume industrial polymer in the world for making a wide range of commercial products that touch nearly every aspect of our daily lives, such as automobile parts, pipes, packaging films, household bottles, baby diapers, and so on.

June 01, 2011

The presented ion chromatographic method is used for the simultaneous determination of HF, HNO3, H2SO4, short-chain organic acids and H2SiF6 in acidic texturing baths that are used in the wet chemical etching process of solar cell production.

June 01, 2011

Synthetic cannabis products have garnered a great deal of media attention recently. Countless products are being sold at smoke shops, convenience stores, and online sites.

June 01, 2011

Using a bonded polymeric zwitterionic stationary phase, in HILIC mode, polar quaternary herbicides like Diquat can easily be retained, with good peak symmetry. The impact of ionic strength and organic content in the mobile phase is discussed.

June 01, 2011

BioPharma Compass? is a fully automated solution for the rapid characterization of biopharmaceutical products such as proteins, peptides, RNA, and DNA. This push button solution assists nonspecialist operators to generate high quality, accurate data for automatic comparison with laboratory reference standards. Automated, visual reports are then generated for each sample and important information regarding a products purity and identity can be observed at a glance. In this application note, we will apply the BioPharma Compass workflow to the QC characterization of two proteins including intact IgG1 and digested transferrin.

June 01, 2011

Resistive glass tubes and plates are designed to guide ions by generating a uniform electric field. PHOTONIS resistive glass products are composed of a proprietary lead silicate glass that has been specially processed to create a resistive layer at the surface. The resistivity can be varied over several orders of magnitude to suit the specific application.

June 01, 2011

EPA is updating method 525.2. The CCL3 includes 104 analytes. UCT has evaluated the recoveries of these compounds, including the current list, using proposed changes to the method with the C18-based UCT ENVIRO-CLEAN? 83 mL Extraction Cartridge ECUNI525.

June 01, 2011

Fast, flexible platforms for peptide quantification are needed, particularly for a discovery setting. This type of methodology would be especially advantageous in the case of amyloid beta (a?) peptides.

June 01, 2011

Benzylideneacetophenone forms the central core for a variety of important biological compounds, known collectively as chalcones. Many of these compounds have significant medicinal value as they demonstrate antibacterial, antifungal, antitumor, and anti-inflammatory properties.

June 01, 2011

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.

June 01, 2011

Gelatin is the denatured form of collagen, the main component of skin, bone, and connective tissues of animals. Its special properties are a sharp sol-gel transition, low sol viscosity, and high effectiveness as a protective colloid.

June 01, 2011

This study demonstrates a faster method of analysis when coupling a simplified and effective SPE procedure with a core-shell HPLC column and LC–MS-MS detection.

June 01, 2011

One of the biggest debates in clinical medicine currently revolves around understanding the proper levels of vitamin D in patients' plasma.

June 01, 2011

Biogenic amines are present in protein-rich foods such as fish, meat, and milk. Their concentration increases during food decomposition.

June 01, 2011

Hydroxymethylfurfural (HMF), an organic compound containing aldehyde and alcohol functional groups, is naturally found in very low amounts in sugar-containing foods.

June 01, 2011

A new, efficient, effective, and sensitive sample preparation application for the extraction of the catecholamines epinephrine, norepinephrine, and dopamine from human plasma at significantly low levels using EVOLUTE WCX, a resin-based mixed-mode sorbent with an optimized combination of nonpolar (hydrophobic) and weak cation exchange interactions.

June 01, 2011

Barbiturates are a class of antidepressants whose abuse and addiction by recreational users has become a widespread problem (www.nlm.nih.gov). In our work we strived to streamline the barbiturate screening process to provide a fast, cost-effective, and reproducible method from start to finish for forensic labs who are involved in high-throughput processing.

June 01, 2011

International regulations on maximum residue levels (MRLs) of pesticides in food cover hundreds of individual contaminants at the 10 ppb or below range. The analysis of citrus oil for pesticide contamination holds specific challenges.

June 01, 2011

Endothall is a widely used herbicide for both terrestrial and aquatic weeds. Exposure to endothall in excess of the maximum contamination level (MCL) can cause illness. Endothall is regulated by the U.S.

June 01, 2011

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.

June 01, 2011

The chiral analysis and purification of proton pump inhibitors (PPIs) has become a popular topic as more of these drugs fall out of patent protection each year. Due to their wide range of enantiomeric selectivity, a set of polysaccharide-based chiral stationary phases (CSPs) was screened to identify methods for the successful enantioseparation of four benzimidazoles; rabeprazole, lansoprazole, omeprazole, and pantoprazole.

June 01, 2011

The chemicals 2- and 4-methylimidazole (2-MI and 4-MI) are by-products produced during the manufacturing of caramel coloring ingredients used to darken food products such as carbonated beverages and soy sauce.

June 01, 2011

Anthocyanins are a sub-class of naturally electron deficient and powerful antioxidants called flavonoids that are responsible for the red, orange, and blue coloration in fruits and flowers.

June 01, 2011

Tea, one of the most consumed non-alcoholic drinks worldwide, contains catechins that are powerful antioxidants thought to provide many health benefits, including reduction of cholesterol and obesity, and protection against cardiovascular disease and cancer.

June 01, 2011

PCBs are a group of synthetic organic chemicals that contain 209 individual compounds (known as congeners) with varying harmful effects. PCBs enter the environment as mixtures containing a variety of individual components.

June 01, 2011

High performance time-of-flight mass spectrometry (TOF-MS) is applied to the analysis and characterization of complex biological samples. High mass accuracy, high resolution, and accurate relative isotope abundance are all applied to the determination of analytes covering a range of concentrations in complex matrices including plasma and urine. Qualitative and quantitative evaluations are provided and include demonstrations of the impact of high-performance MS on sensitivity and selectivity. The ability to leverage high-performance MS in conjunction with a broad dynamic range in rapid ultrahigh-pressure liquid chromatography (UHPLC) analyses to identify unknowns and to propose putative metabolic biomarkers is demonstrated. The impact of speed of analysis and selectivity to the depth of coverage and accuracy of the analyses are discussed.

June 01, 2011

Glyphosate is a broad-spectrum herbicide widely used around the world. Monitoring of glyphosate in crops and water is mandated in many countries.

June 01, 2011

This study evaluates the performance of a C18 core-shell phase that incorporates a C18 ligand with iso-butyl side chains. The Kinetex? XB-C18 HPLC/ UHPLC column delivers a fast and effective separation of several common preservatives in cosmetics.

June 01, 2011

Due to the increasing number of toxic pesticides being used throughout the world, a robust method for positively identifying low levels of multiple classes of pesticides is required. A Zebron? ZB-MultiResidue? column is used with GC–MS to identify over 100 common pesticides.

June 01, 2011

Testosterone was extracted from human serum by strong anion exchange polymeric SPE and analyzed using a Kinetex C18, 30 ? 2.1 mm, 1.7 ?m column and positive polarity ESI LC–MS-MS system. Kinetex sub-2 ?m core-shell technology offers higher efficiencies than traditional sub-2 ?m columns, producing greater chromatographic resolution, sensitivity, and higher peak capacities.

June 01, 2011

The Consumer Product Safety Improvement Act of 2008 (CPSIA) requires testing of child care products and toys for selected phthalate esters by GC–MS.

June 01, 2011

This note describes the use of the AB Sciex TripleTOF? 5600 LC–MS-MS system and data processing using the XIC Manager software to screen extracts of fruit and vegetable samples for pesticide residues.

June 01, 2011

Optical fibers are routinely used in liquid chromatographic detectors as a means of simplifying optical designs. Selection of the appropriate fiber is an important factor in achieving optimal system performance.

June 01, 2011

With advances in instrumentation and without regulatory method constraints, 1,4-dioxane can be detected at the part-per-billion (ppb) level, despite its poor purge efficiency. This application will manipulate purge and trap, as well as GC–MS parameters, to create a more efficient method to reduce cycle times. This study will utilize a Teledyne Tekmar Atomx Automated Sample Prep System in conjunction with an Agilent 7890/5975 GC–MS. A linear calibration and method detection limits (MDLs) for 1,4-dioxane will be established using this method.

June 01, 2011

Vitamin D deficiency has become a topic of interest in recent publications (1–3). Vitamin D is present in two forms, Vitamin D3 and Vitamin D2. D3 is produced after ultraviolet light-stimulated conversion of 7-dehydrocholesterol in the skin (3).

June 01, 2011

Kanamycin and amikacin are aminoglycoside antibiotics used to treat serious bacterial infections. Amikacin is used for infections resistant to other aminoglycosides because it is less susceptible to enzymatic reactions.

June 01, 2011

Click the title above to open the LCGC North America June 2011 Application Notebook, Vol 29 No s6, in an interactive PDF format.