494 SHORT COMMUNICATIONS

1’. A. GHARLWOOD

The National Institute for Medical Research The Ridgeway, Mill Hill London N.W.7, England

Received August 21, 196S

Device for Automatically Starting the Flow of

Eluting Buffer after Application of Large

Sample Volumes to Chromatographic Columns

When applying a large volume of sample to a chromatographic column, it is sometimes rather difficult to complete the sample application and start the eluting solvent at a time of day which is convenient. To elimi- nate this inconvenience, we have used the arrangement shown in Figure 1.

Sample Reservoir

Buffer Reservoir

Approx 2 Feet

FIGURE I

SHORT COMMUNICATIONS 495

The basis of its operation is the use of a one-way valve maintained in a closed position due to pressure exerted by the sample. When sample ap- plication is nearly completed, this pressure is removed, the check valve opens, and the eluting buffer begins to flow.

We have routinely used 2 liter aspirator bottles as reservoirs for sam- ple and eluting buffer, although containers of different capacity could be used; nor is it necessary that the containers be of equal size. The check valve was purchased from Nalge Co. (catalog No. 6120).

The sample is introduced into the reservoir and allowed to flow into and fill the connecting tubing, thereby closing the one-way valve. The reservoir of eluting solvent, equilibrated with atmospheric pressure through the Mariotte tube, is then connected to the check valve and flow onto the column initiated. If the desired flow rate is not attainable with atmospheric pressure, the rate may be increased by applying increased (and equal) pressures through the Mariotte tubes in the reservoirs.

ERIC JONES J. E. WILSON

Biochemistry Department Michigan State University East Lansing, Michigan 488W

Received September 20, 1968