What Do You Look For In An HPLC Column . . . Efficiency, Dependability, Extended Column Life? You Will Find All This And More In The Hi-Chrome Reversible.. .Take A Look
Swagelok ZDV linings with rigid 2 micron Irils
Flow direction indicated A:B or Β A
The Hi-Chrom Reversible column is a combination of a five-micron spherical packing, rigid zero-dead-volume fittings, and a proprietary packing method. The resulting column is so tightly and uniformly packed it can be used equally well in either direction. This means that now, for the first time, longer column life and lower back pressure during that life can be had by the periodic reversal of an HPLC column. Consider these benefits: • Extended Column Life Reversing t h e Hi-Chrom column flushes debris from the entrance frit and holds fines near their point of origin. • High Efficiencies All Hi-Chrom Reversible HPLC Columns show a minimum of 45,000 plates per meter during quality control testing. • Durability The Hi-Chrom Reversible Column is rugged enough to withstand expected mechanical shock from ship ping and inadvertent dropping. • Spherical Packing The packing, Spherisorb, as widely acknowl edged, yields longer life, lower back pressure, and excellent efficiency. • Fully Tested And Guaranteed If for any reason you are not completely satisfied with your HiChrom reversible HPLC Column, return it to Regis for a full refund. WORKS
EQUALLY WELL IN DIRECTION
Test 1
Β - A
Te»t2
Column: Hi-Chrom Reversible Hexyl Mobile Phase: Methanol/Water 8 0 / 2 0 F l o w Rate: 0.6 m l / m i n Peaks: (1) Piperonal, (2) Naphthalene, (3) P h e n a n t h r e n e and (4) Dibutylphthalate
25cm « 4.6mm ID - 1/4" DD Flow direction indicated A B or Β A Figure 2
COLUMN EFFICIENCY
Variations in instrumentation may cause the same column to give different efficiencies on different instruments. Because of this a "guaranteed" plate number is not realistic. However, we do say this: No Hi-Chrom Reversible Column is sold that does not produce at least 45,000 plates per meter on Regis instrumentation. COLUMN PERFORMANCE
Each Hi-Chrom Reversible Column is run through a series of tests to make sure you receive a top quality column. Each column is shipped with two test chromatograms (one in each direction) and a computer-generated performance report (see Figure 1). Also included with the column is a test mixture so you can check the column performance. Figure 1
Test Conditions
Computer-Generated Performance Report
Results: Pressure Peak Identification Test Peak C h a r a c teristics: Plates Per Meter Capacity Factor
R E V E R S E FLOW A N D EXTENDED C O L U M N LIFE
The ability to reverse flow is an outstanding and unique feature of the HiChrom Reversible Column. Reversing the flow leads to benefits which extend useful column life: • Clean outside frit surfaces. Reverse flow washes away dirt from the entrance frit. • Deposit-free columns. Reverse flow, especially the reverse flow of pure unbuffered solvent, dissolves and carries back out of the column deposits that may have built up near the column entrance. • Fine-free inside frit surfaces." As a column ages, fines are formed by dissolution of the silica packing materials. Periodic reversal tends to hold fines harmlessly near their point of origin. Whereas, fines experiencing only unidirectional flow slowly migrate to the exit frit, ultimately plugging it. • Retardation of back pressure increase. Regularly reversing a column very effectively delays increase in column back pressure. (Figure 2) CIRCLE
181 ON READER SERVICE
Reverse Column Reverse Column
Test Number
COLUMN
REVERSING MINIMIZES BACKPRESSURE
In one set of 30 tests, for instance, 80/20 methanol/water was pumped continuous ly through a column (except, of course during reversal). The column was tested periodically (30 times), and reversed occasionally. The tests ran 24 hours a day for several days (the gap between tests 15 and 23 corresponds to 64 hours continuous pumping in direction A-B). The tests demonstrate the dramatic decrease of column back-pressure that often accompanies column reversal. DURABILITY
Column
EITHER
Unlike the c o n v e n t i o n a l HPLC Column which has either a flow direction arrow or labeled entrance and exit ports, the Regis Hi-Chrom Reversible HPLC Column has its ends labeled A and B. Thus the flow direction can be indicated as A:B or B:A. The following chromatograms show that Hi-Chrom columns can be used with flow in either direction without loss of efficiency or change in performance.
A - B
5 micron Spherisorb packing
Easy-to-read color-coded label Highest guality stainless steel tubing: polished 316 Li-Chroma
CARD
We repeatedly dropped a stock HiChrom Reversible Hexyl Column onto the concrete floor from heights up to eight feet, yet saw it then provide over 60,000 plates per meter. We certainly do not advocate such abuse. However, it is obvious that the Hi-Chrom Reversible Column can withstand shipping and normal handling that may include inadvertent dropping. O R D E R I N G INFORMATION
Code No. Description Price 731001 Silica $250 ODS-CIH 270 731018 270 731006 Hexyl-Ce 270 731003 Amino 270 731005 Nitrile Each Hi-Chrom Reversible HPLC Column includes: an Operational Manual, two test chromatograms (one for each direction of flow), computer generated performance report, test sample, and a column log to assist you in keeping a history of your column. If for any reason, you are not c o m p l e t e l y satisfied with the performance of your Regis HiChrom Reversible Column, simply return it for a full refund. F r e e H i - C h r o m R e v e r s i b l e HPLC literature available u p o n request.
Column
Regis 8210 AUSTIN AVENUE MORTON GROVE, IL 60053 PHONE NUMBER (312) 967-6000
