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An Elficient and Inexpensive Temperature-Controlled Chromatography Column The literature~wtement."Allpurilimtionsteps rhould hr c a r r d ~ out at 4'C." can hewme most diinrurdging if cold m(1111 t o r i l i t i ~are nut rwdily availilblc at your indturion. Although mvrt steps iu a purification procedure can he carried out on ice and some techniques such as dialysis can be performed in arefrigerator, chromatographic steps are impossible unless some means can he devised to cool the chromatoeraohv column. While costlv. . iacketed columns for chro- - ~ ~ matography are available, we have found that relatively inexpensive temperature-controlled chromatography columns can he quickly and easily constructed from old distillation columns. The simplest method we have found for adapting the distillation column is to use disposable polypropylene syringes to form the base of the chromatography column. These syringes are inexpensive and available in diameters ranging from 0.5cm to 2.5cm to adapt easily to anv size column. After heine cut to an aooronriate length with a ~~, .. . pair oisrissors, they can he snugly fir into the end of a n~ndenuerby the use of ruhtm tuhing around the body uf the cut syringe. Asmnll f ~ l t epad r ran b~ prepared twm coarse tiltrrinl: material. Thp filter pad can be anything from elaborate chromatography filters to extra eaarse filter paper or even something as simple as layers of nylon or cotton. Whatever the bed support choice, the flow rate should he tested before the column is packed. Good column flow rates and seoaratians are normallv obtained due to the small dead volume created bv the roocove structure of the ~yrinyetip. Inexpensiw stopcorks are readily availalrlcl to fit standard syringe tips or a shon jrrtion of tuhing and a Hoiiman scrPu clamp can h t used to contrul flow. To cool the column, ice water (or warm water, if needed) is oumoed through the condenser with the return line draining hack into ihe same container. By insulating the water with an inexpensive styrofoam cooler the column temperature can be controlled overnight without being attended. Even without the water-cooling system, the condenser can serve as an inexpensive all-purpose column of convenient size for use in both secondary schools and universities.
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These items can be purchased horn eiWler Medex hc..Hillierd, Ohio 43026.Cat. #MX411 or Bio-Rad, Richmond, #732-9009.
California 94804, Cat.
Bambi L. Henderson and Daniel J. McLoughlin Xavier University Cincinnati, OH 45207
430
Journal of Chemical Education
