Temperature typically only has minor impacts on GPC separations, but it should be considered nevertheless. Elevating the column temperature can help improve solubility of some analytes which may improve the resolution of poorly soluble analytes. Further, increased column temperature can also reduce mobile phase/diluent viscosity mismatches which can improve the performance of a separation. One caution one must consider with elevated temperature relates to the flash point or boiling point of your mobile phase solvent. Although it is sometime tragically overlooked, one does not want to do a separation at a temperature anywhere close the flash point of a mobile phase.

The Glycans are typically released from the proteins by PNGase F in buffer solution and then labelled using 2-AA or 2-AB. The samples can then be cleaned up using a HILIC based SPE sorbent such as the bioZen N-Glycan Clean-up plate under typical HILIC conditions to remove excess labeling reagent, salts and surfactants.

Pressure is released at 3.0 +/- 0.5 Bar (1 Bar = approximately 14.6 PSI) The pressure release will split and vent to prevent the seal and vial from breaking. This prevents instrument down time and provides added lab safety Only use pressure release for high temperature work For the highest quality vial and cap products, we recommend Verex. Our vials and caps are manufactured to provide high quality, state-of-the-art solutions for your most challenging, sensitive applications.

Phenomenex has a variety of preparative C18 columns to choose from. If the you are looking for a material that can handle large sample volumes then Luna C18(2) would be the best option. Gemini NX-C18 offers extended pH stability for high pH analyses and a different selectivity to Luna C18(2). Kinetex core-shell columns are best suited for those who are looking for high efficiency preparative applications often where closely eluting impurities pose a problem. Kinetex C18 is also fully scalable from UHPLC to Prep so it is perfect for labs that require the same selectivity across multiple particle sizes. Luna Omega Polar C18 and PS C18 offer a different selectivity to more traditional C18 phases and would be ideal for analysts who need a different selectivity or greater retention of polar compounds.

The alkylamine used directly affects retention time, with longer chains leading to increased retention, e.g. hexylamine will show longer retention times than triethylamine. There is also a difference in solubility so generally gradients need to be adjusted to allow for this. Generally, the effect of ion-pair is oligo-specific; for example, Gapmers longer amines offer better resolution whereas for siRNA shorter amines offer an improvement in resolution.