Application Notes

Acrylamide is a neurotoxic compound classified as a probable human carcinogen and genotoxicant (1). In 2002, researchers in Sweden uncovered the presence of acrylamide in certain fried and baked foods at relatively high levels (2).

Biofuels have emerged as an attractive alternative to fossil fuel. Biofuel refers to any fuel that is derived from biomass (typically, plant and animal waste). A common feedstock for bioethanol production is corn stover (leaves and stalks of maize plants left after harvesting). Corn stover processing involves acid treatment to release a mixture of water-soluble carbohydrates, followed by enzymatic reactions to convert the sugars to ethanol.

Pharmaceutical compounds are often difficult to analyze on C18 columns alone because they may be charged or have very similar structures. Imtakt Corporation has introduced a family of multimode columns that are able to overcome these separation challenges: Scherzo SS-C18, Scherzo SM-C18, and Scherzo SW-C18, containing C18, anion, and cation ligands.

This application note shows that unspecific reaction of adenosine triphosphate can be completely prevented due to the iron- and steel-free design using the Agilent 1260 Infinity Bio-inert Quaternary LC System.

Pickering Laboratories specializes in the manufacturing of cation-exchange columns and eluants for amino acid analysis. Post-column derivatization with Ninhydrin offers unmatched selectivity and reproducibility of the analysis for most challenging matrixes.

Positron emission tomography (PET) is one of the most powerful non-invasive diagnostic tools for tracing organ functioning. Quality control of the short-lived radiopharmaceuticals is challenging, not least because of the tough time limits, the radiation issue and the near nanomole radiotracer quantities.

Levels of benzene, toluene, ethylbenzene, xylenes, and styrene (BTEXS) are a concern in olive oil. These compounds find their way into olive trees and hence into olives and olive oil mainly as a result of emissions from vehicles, bonfires, and paints into ambient air near orchards. This analysis uses a PerkinElmer? TurboMatrix? 110 Headspace (HS) sampler with a Clarus? SQ 8 gas chromatograph–mass spectrometer (GC–MS) to achieve detection limits below 5 ng/g and concentrations up to 100 ng/g.

Natural gas and other gaseous fuels contain varying amounts and types of sulfur compounds which can be corrosive to equipment and can inhibit or destroy gas processing catalysts. Small amounts of sulfur odorants are added to natural gas and liquefied petroleum gases (LPGs) for safety purposes. Accurate measurement of sulfur species ensures proper process operation and odorant levels for public safety.

Aniline is an organic compound widely used in the polymer, rubber, pharmaceutical, and dye industries. Aniline and its derivatives (e.g., nitroanilines) are suspected carcinogens and are highly toxic to aquatic life. Because these compounds are thermolabile and polar, the traditional analytical methods require a derivatization step prior to GC analysis.

Selectivity is the most powerful tool to optimize separations in HPLC. This parameter is changed by using different bonded phases or by changing the mobile phase. In this work, Poroshell 120 columns with highly efficient 2.7 ?m superficially porous particles and the Agilent 1260 Infinity Series LC Multi-Method Solution were used to quickly evaluate method development choices for the analysis of steroids.

Low-molecular-weight heparins (LMWHs) are obtained by fractionation or depolymerization of natural heparins. They are defined as having a mass-average molecular weight of less than 8000 and for which at least 60% of the total weight has a molecular mass less than 8000.

This application note will highlight the extraction of EPA Method 508.1 analytes from an aqueous matrix. It will use the SmartPrep Extractor and the DryVap Concentrator system to achieve excellent recoveries while maintaining minimal user-interface.

This application note demonstrates the analysis of intact proteins using a Thermo Scientific Accucore 150-C4 (150 ? pore diameter) HPLC column. Analysis of six proteins ranging in mass from 6 to 45 kDa is carried out in 15 min with pressures compatible with conventional HPLC instrumentation.

Ion mobility spectrometry (IMS) has become widely accepted for the detection of chemical warfare agents, explosives, and narcotics as well as for pharmaceutical quality control and pesticide screening of food. Most currently available commercial IMS units have a resolving power of 10–60.

Thermo Scientific Application Note

Typical chiral stationary phase (CSP) screening paradigms utilize a single alcohol component as co-solvent in its mobile phase. Recent unexpected observations have demonstrated that mixed-alcohol mobile phases can enhance or even introduce peak resolution when none existed in a mono-alcohol system.

This application demonstrates that stringent sensitivity requirements for the detection of potentially harmful primary aromatic amines can be fulfilled when using an Agilent 1290 Infinity LC system equipped with the 1290 large volume injection kit.

Underground storage tanks (USTs) for various petroleum-based substances such as gasoline, diesel fuel, and fuel oil are monitored for leaks as authorized by the Resource Conservation and Recovery Act (RCRA).

Determination and quantification of amino acids are important in many fields. For the HPLC analysis of amino acids, cation exchange mode method has been used with post-column derivatization. Recently, use of reversed-phase mode method is also increasing. However, because of amino acids' hydrophilic nature, they are usually not well retained and have less selectivity by reversed-phase mode without pre-column derivatization steps. In contrast, HILIC mode is an ideal separation mode for hydrophilic compound analysis.

This article discusses GPC and gives examples of the use of the technique in excipient analysis.

Polymer Char Application Note

Concurrent solvent recondensation–large volume splitless injection (CSR-LVSI), an alternative to programmed temperature vaporization (PTV), typically requires a special GC inlet. The technique described here uses an unmodified split/splitless inlet with CSR-LVSI to lower detection limits for the analysis of 1,4-dioxane in drinking water.

Diesel range organic (DRO) compounds have boiling points similar to diesel fuel (C10–C28), ranging from 170–430 ?C. These heavy compounds are amenable to GC-FID analysis; however, important considerations should be taken to ensure reproducible results over repeated injections.

This application note will demonstrate the extraction of 1,4-dioxane from an aqueous matrix using option 1 of EPA Method 522 for 500 mL initial volume sample. It will make use of the SmartPrep Cartridge Extraction system to produce a valid initial demonstration of precision (IDP) and initial demonstration of accuracy (IDA).

Excipients are pharmacologically inactive substances used as carrier and release controllers for active drug ingredients. A significant amount (30–80% solid) of polymeric excipients such as hydroxyl propyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), hydroxypropyl methyl cellulose acetate succinate (HPMCAS), and povidone are used.

This application demonstrates that stringent sensitivity requirements for the detection of potentially harmful primary aromatic amines can be fulfilled when using an Agilent 1290 Infinity LC system equipped with the 1290 large volume injection kit.

Polyimide coated fused silica capillary tubing is widely used in the separation sciences. In some instances a condition called brittleback can appear in the tubing. Its causes and remedies are discussed.

Heterocyclic amines (HCAs) are a class of compounds that are formed when amino acids from meat proteins react with glucose and creatine under high-temperatures, as is associated with frying or grilling over an open flame (1–3). Studies have correlated the consumption of high levels of HCAs with an increased risk of some forms of cancer.

Protein heterogeneity is generated by post-translational modification, decomposition, and a variety of other processes, including chemical modification, denaturation, and aggregation. Since antibodies and recombinant proteins are now widely used for therapeutic treatment, it is essential to evaluate their heterogeneity during development, stability testing, and in the quality control of the final product.

The FDA has made changes to how products containing sunscreen are labeled in the U.S. to ensure they meet the new regulations set forth for safety and effectiveness. The new regulations will require companies that want to use the "broad spectrum" label to test for both UVA and UVB protection.