Gradient Fractionator

The Brandel density Gradient fractionator for 5-40 ml liquid displacement (formerly Isco) produces a continuous absorbance profile as the gradient is collected in precisely measured fractions. Zones that are undetectable by other methods are resolved, and their exact locations plotted.

Fractionation is performed by introducing a dense sucrose or other chase solution into the bottom of a centrifuged tube, thereby raising the gradient intact by bulk flow. Chase solution is injected either by piercing the bottom of the tube with a short needle, or through a needle from the top.

Used with the Brandel Syringe Pump or our single-channel Peristaltic Pump, the tube holder and piercing mechanism provides bulk displacement fractionation at an economical price.

For on-line absorbance monitoring, the fractionator is used with an absorbance detector and density gradient flow cell.

To fractionate without scanning, you can use a universal top-holder in place of the flow cell to channel the gradient through narrow-bore tubing to the fraction collector or detector.

Brandel, Inc. (Biomedical Research & Development Labs, Inc.), 8561 Atlas Drive, Gaithersburg, MD 20877-4135. Tel: 800-948-6506; Fax: 301-869-5570.