Application Notes: LC

Jul 02, 2008
The Application Notebook
By LCGC Editors
Dr. Maisch GmbH is one of the biggest HPLC column manufacturers in Germany, producing approximately 20000 columns per year. The company manufactures analytical columns of 3, 4, 4.6 mm i.d., microbore columns of 1, 1.5, 2 mm i.d., nano-columns of 75, 100, 150 μm i.d., preparative columns of 10, 16, 20, 30, 40, 50 mm i.d. and guard columns. Additionally, the company offers more than 500 different phases, the most well-known of which are Reprosil, Reprosil-Pur, Reprosil Basic, Reprosil Gold (Figure 1), Reprospher and Gold Turbo. These phases are designed for reversed phase, normal phase, chiral, size exclusion and fast liquid chromatography among other techniques.
Jul 02, 2008
The Application Notebook
An effective UHPLC–MS method for high throughput separation, identification and quantification of pseudoephedrine was developed on a Hypersil GOLD PFP 1.9 µm, 2.1 × 100 mm column.
Jul 02, 2008
The Application Notebook
The pressure to save active pharmaceutical ingredients drives the industry to scale-down laboratory processes. This puts the burden on the chemist to choose the appropriate analytical platform that can handle the smallest sample quantities — a challenge that drove the development of HPLC-chip/MS systems for high-sensitivity analyses of small molecules. This article presents data from the technical evaluation of a novel ultra-high capacity HPLC-chip for the quantitative analysis of small molecules using triple quadrupole MS.
Jul 02, 2008
The Application Notebook
The analysis of polar compounds in support of clinical and preclinical pharmacokinetic studies requires an analytical methodology capable of achieving ultra-low detection and quantification limits. The high sensitivity afforded by coupling HPLC with tandem mass spectrometry (MS–MS) has made it the technique of choice in this environment, but it is subject to the following limitations when reversed-phase liquid chromatography (RPLC) is used
Jun 01, 2008
The Application Notebook
By LCGC Editors
The natural colors of the food we eat add greatly to the enjoyment of life. Consequently, the art and science of recreating food's natural colors through the use of synthetic colorants is an important success factor in the food industry.
Jun 01, 2008
The Application Notebook
The continuing and growing trend toward high-speed analysis in all fields of chromatography is also reflected in enantiomer separations. A variety of new 3-μm columns has been designed to meet this need. Applications of CHIRALCEL® OD-3 and CHIRALPAK® AD-3 in some enantiomer separations demonstrate the benefits of transitioning to such media.
Jun 01, 2008
The Application Notebook
The QC for the pharmaceutical industry is based on methods developed on a variety of columns. At Orochem, we have attempted to address method development utilizing unique chemistries such as the OROSIL C18 to analyze a wide range of acidic, basic, and neutral compounds. Data is presented on a few representative compounds and unique separation criteria with their associated chromatograms.
Jun 01, 2008
The Application Notebook
Urea and allantoin are added to cosmetic products for skin protection and regeneration, especially for the treatment of dry skin, and analyzed for QC purposes. As polar compounds, they are not ideal for reversed-phase HPLC separations. Neutral hydrophilic compounds like urea and allantoin are best analyzed by hydrophilic interaction chromatography (HILIC). Traditional HILIC columns use silica modified with a hydrophilic group such as diol or cyano. Analytes are adsorbed and subsequently eluted with mobile phases containing high percentages of organic solvent (>75%).
Jun 01, 2008
The Application Notebook
There has been an increasing interest in the presence and availability of compounds in plant materials that may possess bioactive properties, in particular, antioxidant activity. Some of these compounds have been attributed to possess anticancer, antiaging, and antimutagenic properties as well as other health benefits (1). The types of plants that have been investigated cover a vast range from common foodstuffs to regional or exotic materials. Plant parts under study have included portions that are traditionally known to be edible, as well as sections that are considered "waste" or used for animal forage. Because most screening techniques involve lengthy separations, high throughput HPLC methods are desirable.
Jun 01, 2008
The Application Notebook
Aminoglycoside antibiotics are among those commonly used in animal feeds to manage intestinal microorganisms. The beneficial effects include improved growth and generally healthier animal populations. Use of antibiotics creates a demand for analytical procedures to verify concentrations in pre-mixes and feeds and in some instances for residue analysis in animal products.
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