Application Notes

The benefits of olive oil as part of a healthy diet reaches back to the 1950's. Methods were developed to determine benzene, toluene, ethylbenzene, xylenes and styrene (BTEXS) by static headspace methods.

Agarose is a polysaccharide produced from seaweed that forms a gel at room temperature. The characteristics of agarose gels depend on the agarose concentration, solvent, weight-average molar mass, and molar mass distribution.

UHPLC columns can significantly improve chromatographic separations, but they also present unique challenges. Once the UHPLC system components are optimized, perhaps your greatest concern is protecting the column from the damaging effects of microparticulates and sample contaminants.

Tetracycline (TC), a common antibiotic used to treat urinary tract infections, acne, gonorrhea, and other conditions, yields a toxic degradation product, 4-epianhydrotetracycline (EATC). General Chapter 226 of the U.S. Pharmacopeia and National Formulary (USP-NF), referred to by monographs for epitetracycline and drug products containing tetracycline hydrochloride (TC-HCl), prescribes an antiquated assay for EATC impurity in TC.

For the analysis of biotherapeutics, size-exclusion and ion-exchange chromatography are typically conducted under native separation conditions, requiring high ionic strength, 100% aqueous eluents.

Synthetic fused silica capillary tubing is used in the manufacture of most gas chromatography (GC) columns. In this note, we discuss recent advances in the dimensional control of the most popular tubing sizes.

Silymarin, derived from the milk thistle plant, has been used as a natural remedy for the treatment of a number of liver diseases as well as in the protection of the liver from potential toxins. More recently, silymarin has been connected to antitumor promoting activity (1). It is therefore of interest to have available analytical methods for the analysis of silymarin components in various matrices.

Various triarylmethane and fluorescent dyes are used in aquaculture as antibacterial, antifungal, and anthelmintic agents for the treatment of fish disease. The FDA has banned the importation of certain fish from several countries due to possible contamination of these food products.

By identifying maturation tracers and molecules commonly responsible for taste defects, gas chromatography–mass spectrometry (GC–MS) augments expert opinion with objective and quantitative information. When using a solid phase micro extraction (SPME) method, GC–MS requires very small sample sizes and a minimum of sample preparation while providing rapid analysis of target molecules. GC–MS can provide an automated technique with repeatable results for detecting all of these compounds.

Saccharides are fundamental substances that express various bioactivities and may exist independently or form complexes with proteins or lipids.

Blueberries are extracted into acidified methanol and analyzed for anthocyanins with a methanol/formic acid gradient via UHPLC/MS; four different Agilent ZORBAX RRHD stationary phases are quickly evaluated.

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.

Basic compounds often require basic additives in the modifier to improve peak shape and resolution in SFC (1). These additives can be difficult to remove post-purification (2).

Describes the preparation of a reversed-phase monolithic column with an optimized porous structure to separate intact proteins using LC–MS.

Polymer Chas Application Note

Describes how asymmetrical flow field flow fractionation (AF4) can be used to characterize intermolecular interactions in multifunctional polymers used in drug delivery.

Ultrahigh-performance TOF–MS is utilized for the identification of a common pharmaceutical compound's metabolites. Mass spectral analysis is combined with UHPLC and post-source fragment ion generation to facilitate analysis.

Diclofenac is a slightly acidic (pKa = 4.0) non-steroidal anti-inflammatory drug (NSAID) that has been used as a post operative pain reliever in adult and pediatric patients.

The types and amounts of sugar in animal feeds are as important as the amount of protein, minerals, and fats in the determination of nutritive value. We developed a simple and sensitive HPLC method for analyzing six sugars in animal feeds – sucrose, fructose, glucose, galactose, maltose, and lactose. Post-column derivatization reagents convert reducing and nonreducing sugars into fluorescent derivatives, which greatly improves the sensitivity and selectivity of the detection.

Analysis of semi-volatile organic compounds by GC–MS according to well-established methodologies requires integration of a complete system of GC–MS instrumentation and software for data interpretation, analysis, and reporting. While the overall process of analyzing these target compounds is a mature technique, there are continuous innovations that allow laboratories to meet lower detection limits and analyze new compounds to comply with changing regulations, with higher throughput and improved quality.

Air pollution remains a global concern due to its impact on human health and the environment. Compounds known as "air toxics" are of particular importance in this respect, and US EPA methods TO-15 and TO-17 describe how to test air samples for the presence of these compounds.

The iDQuant? Standards Kit for pesticide analysis of certified reference material (ISP Guide 34, IOS/IEC 17025, and ISO 9001:2008) includes 204 pesticides in 10 mixes at a concentration of 100 ?g/mL. This kit has been designed to eliminate the need to source pesticides individually, and measure each one manually. This allows users to setup, verify, and validate the performance of pesticide screening methods faster.

EPA Method 8270D is used to determine a list of up to 243 semi-volatile organic compounds that are neutral, acidic, basic, and are soluble in methylene chloride. Semi-volatile water samples can contain varying amounts of suspended particulates and/or sediment due to either the source of the water, or the collection technique. By elevating the pH of semi-volatile samples, precipitates can form and result in an emulsion that can create problems for an efficient extraction with traditional techniques. These types of samples, due to their sediment content, have historically proven very challenging when using solid phase extraction (SPE).

Purification of active pharmaceutical ingredients (APIs) often yields high numbers of fractions, leading to a bottleneck of fractions to dry-down and subsequently analyze. UV-based fraction collection based on slope or threshold values offers some specificity and reduction in the number of fractions collected compared to basic time- or volume-based collection.

In this application, we present the feasibility of NH2P-50 4E, polymer-based amino HILIC column, for the structure analysis of N-glycans in biological samples. Characterization of glycan is important since different biological properties of glycoprotein play unique roles on pharmacokinetics, stability, and antigenicity.

The US EPA regulates the testing of 20 specific chlorinated pesticides under the official Method 8081. Zebron MultiResidue columns achieve baseline separation of all of these analytes with short run times, providing greater confidence in identification and increased lab productivity.

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.

Bilberry (Vaccinium myrtillus L.) extracts are high in anthocyanin content and are widely used in nutritional supplements for improving visual acuity and treating circulatory disorders.

Vitamin K is a group of structurally similar, fat-soluble vitamins that are needed for the post-translational modification of certain proteins, mostly required for blood coagulation but also involved in metabolic pathways in bone and other tissue.

According to law enforcement and health officials, "bath salts" are powerful synthetic stimulants, designed to be comparable in effect to cocaine or methamphetamine, carrying similar risks. Unlike cocaine or methamphetamine, these stimulants are currently legal in many parts of the United States and available at a low cost in many convenience stores and head shops.