Particles entering the chromatography system can block capillaries and valves, increase wear, and damage the column or system. Especially with aqueous solvents, algae and other microorganisms can grow and deposit in the system and block the solvent line filters. Blocked capillaries or filters can cause increased or unstable system pressure.

TIP

In a Vanquish Core system, normal-phase (NP) compatible solvents and additives may be used if the system modules have been modified for NP applications. Refer to the Vanquish System Operating Manual.

For optimum performance of the chromatography system, observe the following guidelines:

Solvent Quality and Filtration

  • Use high-quality high-purity solvents (filtered) and additives as required by the application, for example, UHPLC-grade or LC/MS-grade. If a fluorescence detector is used in the system, consider using fluorescence-grade solvents.

    Filtered high-purity solvents are usually labeled accordingly by the vendor.

  • Use high-quality water for example, UHPLC-grade or LC/MS-grade (0.2 µm filtered).

  • When you use water from water purification systems, polymeric contamination may occur if the purification system is not maintained properly.

  • When preparing salt solutions or buffers and preparation is complete, use membrane filtration (0.2 µm) to remove any particulate matter and to reduce microbial growth.

  • Use fresh solvents at regular intervals. Avoid adding up (refreshing) solvents. With premixed solvents, be especially sure that they are properly prepared and fresh.

  • Always use the appropriate solvent line filters as recommended by Thermo Fisher Scientific. Check the filter frits for permeability at regular intervals and replace them as necessary.

  • For best seal performance, do not recycle or recirculate solvents.

  • Note the special properties of the solvents, such as viscosity, boiling point, or UV absorption.

Solvent Reservoirs

  • Before filling a solvent reservoir, rinse the reservoir thoroughly with a high-purity solvent.

  • To reduce the growth of algae, consider using amber glassware or using appropriate additives, for example, formic acid.

  • Avoid using methanol from aluminum reservoirs.

Flushing after Operation

  • Flush out buffers and solutions that form peroxides.

  • Never leave buffers, salt solutions, or aggressive solvents in the system for a longer period without flow.

  • Before you change from a buffer or salt solution to organic solution, flush the system thoroughly with de-ionized water.

  • Before you change solvents, make sure that the new solvent is miscible with the previous solvent. If the solvents are not miscible, flocculation may occur.

    Mix immiscible solvents with an intermediate solvent to replace them step by step. For example, use isopropanol.