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Fixed and Adjustable Flow Splitters for Pre and Post Column Applications
Published: May 6, 2025• Precise split ratio control
• Low dead volume fluidic design
• Stable to changes in viscosity or pressure
• Quick and reproducible split ratio adjustments
• Rugged construction for high pressure operation
• Available with both adjustable and fixed metering
• Ideal for LC/MS and capillary chromatography
Advantage Flow Splitters make it easy to create split ratios from 1:1 up to as high as 20,000:1 and are available in three distinct formats: fixed, adjustable, and multi-port fixed. Splitters are available for both analytical range flows of 0.1-10mL/min and prep flow rates of 5.0-40mL/min.
The Fixed Flow Splitter provides a fixed split ratio with an extremely low dead volume. Delay volume on the low flow/capillary side is as low as 100 nanoliters depending upon the resistor cartridge selected. The flow split ratio is not affected by changes in solvent viscosity, density or pressure and is extremely stable and reproducible. Unlike conventional splitters that use long lengths of capillary tubing, the Fixed Flow Splitter uses compact fluid resistor elements which are cartridges designed for easy replacement. Because of the extremely low internal volume of the fluid resistors, the solvent composition in both resistors at any instant in time is the same, therefore, viscosity changes associated with gradient runs do not impact the split ratio. Flow rate and viscosity changes will change the back pressure generated by the splitter, but will not affect the actual split ratio. Our Flow Splitters are configured for either post-column or pre-column applications.
The Adjustable Flow Splitter incorporates a metering valve, enabling split ratios to be modified frequently with flow changes that are stable and reproducible. The flow path contains two fluid resistors that form a parallel flow path. The low flow stream passes through a fixed resistor while the high flow rate passes through an adjustable fluid resistor (metering valve).
Both the fixed and adjustable flow splitter can be used for isocratic or gradient applications. Running gradients with solvents of different viscosities may result in a reproducible change to the split ratio.