EARL FRIEDEN Florida State University, Tallahassee, Florida
T H E Warbure: manometric technique for determining small changes in the volume of a gas phase is widely nsed in biochemical and clinical research. Washing the specialized glassware nsed in this technique is a time-consuming chore, particularly when extra precautions are necessary for highly sensitive enzyme work. A single Warburg vessel may be individually handled and drained as many as 15 times in one complete washing. This large amount of treatment also increases the chance of breakage of these expensive, specialized pieces of glassware. A simple Warburg vessel washer aid may he constructed by a relatively inexperienced technician. Dimensions for such a washer holding 14 ordinary Warburg vessels are given in the accompanying figure. All parts of this gadget are of stainless steel using stainlesssteel wire cloth, type No. 304, '/=inch mesh, 0.028-inch diameter, $1.30 per square foot,' and approximately 18gage stainless-steel sheet. These will show some discoloration on continual immersion in solutions of hot, concentrated nitric acid, but no extensive decomposition. The discoloration' is not believed to contribute significantly to contamination of either vessels or washing solutions. The stainless-steel handle is attached to the bottom of the vessel container by threading stainless-st& wire through the partition and tying these wires to the handle. The handle is bent in the long axis to form a curved surface more comfortable to handling. The partition is also wired to the sides for reasonable rigidity. Two braids of stainless-steel wire, attached to a side and the bottom of the basket, are used to lock the basket lid by insertion through holes in the descending part of the lid. All exposed edges of the wire cloth are bent over and sewed to the adjoining side in order to eliminate sharp edges. The lid is wired on using several loose wirings with stainless-steel thread as hinges. Once the vessels are locked in the basket, the entire container may be immersed with impunity in such diverse solvents as ~etroleumether, hot, concentrated nitric acid, as weli as all aqneous'solutions. Rinsing ~~~~~
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Obtainable from Edward J. Darby & son,1517 ~~~~~~t~~~ Ave., Philadelphia 22.
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solutions may he introduced directly through the pores of the wire cloth. It has been estimated that the use of this simple washer aid reduces the time required for washing to one-third t o one-half the time required by other methods. After rinsing, the vessels can be dried in an oven in an upside-down or other desirable draining position. Thus, for 14 vessels, the number of individual vessel handlings - can be reduced from 210 to about 28. It is obvious that similar problems related to cleaning other specialized glass equipment may. he solved by custom-made equipment designed as described in this communication. We have found it very convenient to use stainless-steel wire-cloth baskets for drying and storing small glassware such as pipets, volumetric flasks, etc. Because the stainless-steel wire cloth is expensive, a paper or cardboard pattern is usually designed prior to the nse of the metal. ACKNOWLEDGMENT
The acknowledges the valuable advice and technical assistance of Harry T. Owens and Gene Talmadge Sellers.
