TECHNOLOGY
"Filter Press" Scales Up Electrophoresis Modified unit uses d.c. field to separate colloids by charge and size, can process liquids commercially A modified filter press may be one an swer to the long-standing problem of how to scale up electrophoresis. Dr. Milan Bier of the Institute of Applied Biology in New York has worked out such a design, predicts that it could be a practical commercial way to make electrophoretic separations continu ously. Dr. Bier's technique is similar to membrane dialysis—used by Ionics, inc., to desalt water, for example—but has a different purpose. It uses cheap, conventional membranes in place of the expensive, selective ion exchangers Ionics uses. And rather than separat ing ions or dissolved materials, as the dialysis does, Dr. Bier's process sepa rates charged colloidal particles. Forced-Flow Electrophoresis. The method itself is very simple, says Dr. Bier (who is also on the chemistry faculty at Fordham University). Building on the filter press principle, he separates filter frames alternately with a filter sheet and a semipermeable membrane. For filter sheets, he uses commercial filter paper or porous poly
vinyl chloride battery separators; he makes his membranes from materials such as regenerated eellulosic sausage casing. Each membrane-filter sheetmembrane unit is a cell. At each end of the set of filters stands a platinum electrode the same size as the useful filter area. Buffer solution flows between electrodes and the multicell filter pack. This "forcedHow electrophoresis" discriminates according to particle charge as well as particle size. in operation, liquid to be treated Hows in at the top on the positive side between membrane and filter sheet. The cell elements work in parallel. Part of the output drains out the bot tom of the cells on the positive side of the permeable sheet, the rest flows out the top on the negative side. Dr. Bier can control the two outputs in dependently. Most colloidal particles, molecules, or complexes have negative charges, lie explains. Therefore, they migrate away from the filter sheet toward the positive plate and are drawn off in the
liquid going out the bottom outlet. The liquid taken off at the top on the negative side contains only nonpolar molecules or colloidal particles small enough to pass through the filter Current carriers passing back through the filter keep its pores open to pre vent clogging. Separating Globulins. If whole blood or plasma is put through the apparatus, the isoelectric 7-globulins are unaffected by either the current or the filter. They appear at the same concentration on both sides of the fil ter sheet and are drawn off in equal proportion. Continuous treatment of blood in vivo involves pumping the blood from an animal, adding to it an equal part of buffer solution (plus heparin as anti coagulant), and passing the mixture through a cooling coil and into the filter pack. The bottom fraction, adjusted to give 50'ν of the output, contains half the original concentration of 7-globu lins but is otherwise identical with the original input, Dr. Bier says. It is recirculated into the animal's system. The top fraction contains the other half of the 7-globulins, and is dis carded. Continuing the purification can reduce 7-globulin content to any level of hypogammaglobulinemia. Dr. Bier's continuous blood-purifica tion procedure4 resembles in principle the "artificial >AidncyM treatment, but removes 7-globulins instead of urea. So far, however, it has been tried only experimentally with animals, in the first industrial application of this system. Anchor Serum, St. Joseph, Mo., has installed a pilot plant to frac tionate hog serum, dog serum, and other animal sera for veterinary vac cines. High Throughput. Capacity of his system is high, declares Dr. Bier. Throughput of 50 liters per hr. per en ft. of cell space is possible for sen m ι fractionation, he maintains. For other liquid systems, even higher flows are possible. In water treatment (cold sterilization, pollution monitoring) he looks for rates up to 500 liters per hr. per cu. ft. Other potential uses include: • Concentrating viruses. Low lev els of contamination (as in impure water) can be boosted quickly and safely for monitor-testing.
LOWERS GLOBULIN CONTENT. Changing the protein content of blood is one use of forced-flow electrophoresis. Here, blood is drawn continuously from the jugular vein of the ewe, treated to remove half the --globulin, then returned to her system 60
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• Sterilizing water. Bacteria are driven with the electric current and separate completely, giving sterile
DONNA MICHAEL QUILL
&THE
13,300 As the week of September 11 began, Hurricane Donna was barrelling up the Eastern seaboard to keep a smashing Monday date with New York City. The Pennsylvania, the largest railroad system in the world, was closed tight. Occasional bewildered pigeons were the only travelers moving in New York's Pennsylvania station. Yet, during the week of September 11, 13,300 chemists and chemical engineers from 19 countries met in New York. They presented or listened to 1761 papers on the latest technical and scientific developments in their fields. Among the papers' authors were six Nobel Prizewinners. Last spring in Cleveland (the weather was g o o d even if a little on the cold side, and the railroads, including the Pennsylvania, were running) more than 7000 chemists and chemical engineers gave or heard 1122 papers. These were the fall and spring meetings of the American Chemical Society. Out of these meetings came news of developments and discoveries that will influence the careers, the lives, the health, the business and scientific activities of the man on the street for years to come. Some of these developments made the front pages of the papers. Many more made what is the equivalent of the front pages of leading scientific journals. But if you were looking for a carefully balanced, thoroughly considered coverage of the ACS meeting, there is only one place where you could find it. That is in the pages of the journals of the American Chemical Society.
Let's take a look at the way the staff of the ACS Applied Publications covers an ACS meeting. Long before each meeting, the ACS staff of trained chemists and chemical engineers were reading the abstracts of the papers to be given. The editors carefully weighed the relative importance of the developments to be talked about. They consulted leaders in various fields for special help in making their editorial judgments. Twenty-two of the ACS editors worked on the premeeting coverage of the New York meeting for Chemical and Engineering News alone. In New York the top editors and staff members of the Applied Publications went to sessions, talked to authors and session chairmen, re-wrote, revised, and re-edited where necessary. As a result, the September 19 issue of Chemical and Engineering News, in the hands of many of its readers on the 16th, the day the meeting closed, contained a balanced summary of high points of the week's meeting. This was followed by further coverage in the issue of September 26. No other magazine in the world gave anywhere near as complete and thorough a summary of the significant developments announced at the ACS meeting. In the meantime, the editors and staffs of Industrial and Engineering Chemistry, Analytical Chemistry, Agricultural and Food Chemistry, and Chemical and Engineering Data, were studying and weighing the importance of the papers related to their particular fields. Out of the 1761 papers of the New York meeting, they chose those they believe will have most significance to the readers. Most of these will be published in full with required charts, tables, and illustrations. Whether you are a chemist in a laboratory, a chemical engineer in the field, an executive in the chemical process industries, or a teacher in a university, you can look only to the journals of the American Chemical Society for a thorough, balanced coverage of the two most important single events in the chemical world each year, the meetings of the American Chemical Society. Only in these magazines will you find such complete coverage of discoveries and developments that will profoundly affect the science of chemistry and chemical engineering and the management and technology and of the chemical process industries in years to come.
AMERICAN CHEMICAL SOCIETY
APPLIED PUBLICATIONS OCT.
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water without heat, radiation, or chemicals. • Recovering valuable metals. Col loidal catalyst materials respond well to this electrophoretic treatment. • Treating process water to remove valuable or hazardous materials from water being discharged into rivers and streams.
NEW! SAFE! CONVENIENT!
One field where water treatment should be particularly profitable, ac cording to Dr. Bier, is in processing milk whey from the manufacture of cream cheese or cottage cheese. Some 16 billion pounds of whey (contain ing 0.5 to VA protein) go down the drain each year in this country alone, he states. The protein content is too low for economic recovery by existing means, but forced-flow electrophoresis could turn the trick, Dr. Bier feels. The recovered protein would be use ful as an additive for food and animal feeds. Electrofore Corp. (New York City) holds all patent rights to Dr. Bier's process. Research was supported by Whitehall Foundation.
dri-Na f
REAGENT dri-Na is J. T. Baker's sodium-lead alloy containing 10?ύ sodium. dri-Na is the modern way to use sodium in safe, convenient form for
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Write for a Product Data Sheet giving specifications, typical drying perform ance, and other helpful information.
J. T. Baker Chemical Co. Phllllpsburg, New Jersey 62
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Practices and procedures for estab lishing emergency sections in chemical plants are covered in a pamphlet just issued by Manufacturing Chemists' As sociation, 1825 Connecticut Ave. N . W , Washington 9, D.C. The pamphlet emphasizes the organization of safety plans and gives suggestions for making the plan as simple as pos sible, yet able to cope with any pre dictable emergency. Specific opera tions common to any program are item ized briefly. Price is 20 cents.
Solids content of sludges from water and waste treatment can be monitored by a gamma radiation composition analyzer, Charles O. Badgett of In dustrial Nucleonics told the Water Pollution Control Federation meeting in Philadelphia. Such a system, with its instrumentation and control, gets around human error and time delay of currently used laboratory tests, Mr. Badgett says.
A six day meeting of plastics experts gets under way this week in Prague. Representatives to the technical com mittee on plastics of the International Organization for Standardization will meet in committee through the week to consider standards for nomencla ture, definitions, tests, and specifica tions. Among them: methods pro posed for determining tensile proper ties, stiffness, resistance to natural and artificial light, and how mechanical properties change in various chemi cals.
Baker Analyzed'
Tests show that dri-Na reduces water content of solvents satisfactorily without affecting purity. It is safe to use. There is no hazard in disposing of residues: they can be placed directly in water. dri-Na is available in 1- and 5-lb. bot tles from all J. T. Baker distributors.
BRIEFS
Plastic Perch Riggers ride a section of plastic smoke stack into place on a corrosive gas ex haust system fabricated by Heil Process Equipment, Cleveland, Ohio. The 72-in. diameter stack is made of glass-rein forced polyester in 25-ft. flanged sections that are bolted together to form the stack. This one is 150 ft. high. Advantages for the stack cited by Heil: It is lighter, cheaper, and easier to install than lined steel or alloy; it won't corrode and doesn't have to be painted.
Computers may help businessmen level the hills and valleys of the busi ness cycle, predicts Don G. Mitchell, president of General Telephone & Electronics. The reason, he told the ISA's 15th Instrument-Automation Conference in New York: With com puters, you have a good chance to get the right information to the right place at the right time. And, he adds, recent recessions have been caused largely by excessive inventories of which businessmen have not been aware early enough to compensate for them. And when they do correct, they go to extremes, Mr. Mitchell feels, cutting production drastically and going on economy drives—often doing more harm than good.
