Phenomenex

Yarra columns demonstrate significantly higher inertness to ionic interactions versus other GFC columns; however, such chemical characteristics require optimization to operating parameters. In particular, salt and buffer concentration can have a significant impact on secondary interactions which can influence GFC separations.

In this technical note, we report the baseline resolved chiral separation of the most common 19 FMOC protected a-amino acids derivatives under reversed phase separation mode using five unique Lux polysaccharide-based chiral stationary phases.

41 pain management drugs from several drug classifications were isolated from urine samples using the specialized Strata-X-Drug B SPE sorbent and analyzed by LC/MS/MS in under 5 minutes using a Kinetex Core-Shell Technology HPLC/UHPLC column.

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. An ultra-high performance column protection system, specifically designed for UHPLC systems using sub-2 μm and core-shell particle columns, can be used to extend column lifetime (saving both money and time through less frequent column replacement), while minimizing system troubleshooting and downtime.

Nicotinic acid and nicotinamide were extracted from human plasma by performing a rapid protein precipitation using Impact Protein Precipitation Plates followed by HPLC analysis using a Gemini 3 μm C18 100 x 4.6 mm HPLC column and positive polarity ESI LC/MS/MS system. Impact technology offers easy, fast protein removal while providing maximized recovery of the target analytes. The Gemini 3 μm C18 HPLC column produced excellent chromatographic resolution, sensitivity, and high peak capacities.

A new high efficiency GFC column, Yarra, was recently introduced and is significantly more efficient than other GFC columns on the market. In addition to higher efficiency, Yarra columns demonstrate significantly higher inertness to ionic interactions versus other GFC columns; however, such chemical characteristics sometimes require changes to operating parameters. Performing method development for protein aggregation analysis using next-generation Yarra GFC columns will be discussed.

Protein precipitation is compared to a phospholipid removal product, Phree Phospholipid Removal Plates, to assess the cleanup capabilities of each technique. By measuring for total phospholipids using the 184  184 mass transition, LC/MS/MS analysis indicates that Phree Phospholipid Removal Plates result in significantly cleaner samples, reduced ion suppression, and extended HPLC/UHPLC column lifetime. The technique followed a simple procedure that is similar to a traditional protein precipitation, required no method development, and can be automated to provide higher throughput.

Gel Permeation Chromatography (GPC) is principally used to separate polymers and organic molecules based on their size. An important aspect in optimizing GPC separations is column selection, especially when multiple columns are used. Mobile phase selection and column temperature are also important factors that must be considered when developing a method, as they can influence the solubility and viscosity of diluent and analyte respectively. Column, mobile phase, and temperature selection will be discussed to optimize GPC methods using Phenogel GPC/SEC columns.

Kinetex 5 μm core-shell technology columns provide chromatographers a simple solution for dramatically improving the Performance of their methods developed on 5 μm fully porous columns. This newly introduced core-shell media delivers backpressures of a fully porous 5 μm particle at efficiencies equal to or better than a fully porous 3 μm particle. Without the need for extensive method development, replacing the fully porous 5 μm column with the Kinetex 5 μm core-shell column results in improved chromatographic resolution and sensitivity. In addition, the lower backpressure can provide many benefits such as longer column lifetime, higher throughput, and increased system compatibility.

Aeris WIDEPORE is a recently introduced core-shell HPLC | UHPLC column specifi cally designed to provide improved resolution of intact proteins larger than 10 kilodaltons (KDa) in molecular weight. The improved resolution of proteins is accomplished by the use of a new core-shell particle morphology which minimizes protein band-spreading that occurs during diffusion in and out of the coreshell particle. The result is narrower peaks and better resolution of closely eluting proteins. This improved resolution is especially useful for refolding, impurity, and post-translational modifi cation assays on intact biogeneric proteins where very slight differences between intact and modifi ed proteins elute closely on reversed phase columns. Several examples are shown demonstrating the utility of Aeris WIDEPORE core-shell columns for such applications.