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The need to increase the use of low valued co-products derived from the processing of sugar beets has prompted the investigation of the structure of the pectin extracted from sugar beet pulp. The characterization of sugar beet pectin is essential as it has the potential to be used in the production of industrial products, e.g., as an emulsifying agent in food systems.
Analytical Methods to Characterize and Quantify PEG and PEGylated Biopharmaceuticals
June 1st 2012Biotherapeutic peptides and proteins are often PEGylated (covalently bonded to polyethylene glycol polymers) to improve bioavailability, reduce immunogenicity, and extend circulating half-life (1). Achieving the desired properties for each application depends on optimizing the number and site of polymers attached, chain length, and the degree of chain branching.
Glycan Analysis using HPLC with Charged Aerosol Detection and MS Detectors
June 1st 2012Simple, rapid and accurate methods have been developed for the analysis of simple carbohydrates including mono- or disaccharides, or as fairly small glycans (6–11 residues) liberated from glycoproteins using charged aerosol detection combined with mass spectrometry techniques.
Molecular Weight Determination of Low-Molecular-Weight Heparins: SEC/MALS vs. SEC/UV-RI
June 1st 2012Low-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.
Unique Effects of Two Mobile Phase Alcohols on the RegisPack CLA-1 Chiral Stationary Phase (CSP)
June 1st 2012Typical 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.
Size-Exclusion Ultra Performance Liquid Chromatography Analysis of Insulin
June 1st 2012Insulin was the first recombinant pharmaceutical produced. Currently, one of the critical quality control attributes of therapeutic insulin in the US and European Pharmacopoeia (USP and EP) monograph is the level of covalent high molecular weight (HMW) insulin as determined by HPLC size-exclusion chromatography.
Practical Advice for High Throughput Ion Exchange Separations using Non-porous Particles
June 1st 2012Ion exchange is a perfect technique for analyzing large biomolecules such as proteins, peptides and oligonucleotides. These complex compounds contain numerous components (amino acids, nucleotides, glycans etc.) many of which possess a charged side chain or backbone.
Effective Cleanup and Analysis of Metronidazole from Foaming Facial Cleanser
June 1st 2012When working with complex matrices such as personal care products, sample preparation is perhaps the most difficult step of the analysis process. By utilizing a targeted sample preparation technique, such as ion-exchange SPE, analysis can be significantly improved as compared to less targeted techniques such as liquid-liquid extraction.
Resistive Glass Inlet Tubes Increase Ion Throughput
June 1st 2012Resistive 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.
Purge-and-Trap GC Analysis of Methane in Water Samples Associated with Hydraulic Fracturing
June 1st 2012Shale gas reservoirs, such as the Marcellus shale reserve in Pennsylvania and Barnett shale reserve in Texas are a growing source of natural gas in the United States. Hydraulic fracturing or "fracking" involves pumping water, sand, and chemicals at extremely high pressure into deep underground wells to crack open hydrocarbon-rich shale formations and extract natural gas.