LABORATORY OF THE MONTH
Analog computer is used to provide automatic integration of paper electrophoresis patterns and rapid calculations. The instrumental program worked out at t h e Clinical Chemistry Laboratory of the Yale-New Haven Medical Center after adequate on-the-job testing will be simplified into a single purpose instrument, an automatic densitometer
Clinical Chemistry Laboratory Features Direct Readout Instruments A CLINICAL CHEMISTRY LABORATORY which contains a ^*- number of direct readout analytical instruments is an outstanding feature of t h e Clinical Laboratories of the Yale-New H a v e n Medical Center in N e w H a v e n , Conn. T h e Clinical Laboratories, under t h e direction of Dr. D a v i d Seligson, provide analytical, consultative, and teaching services to t h e large complex of 800 p a t i e n t beds and to m a n y clinical research programs. T h e Clinical Chemistry L a b o r a t o r y is one of the four major divisions of t h e Clinical Laboratories' program and performs 200,000 tests per year. T h e n a t u r e of the analyses v a r y from t h e m e a s u r e m e n t of a few n a n o grams of iodine in serum t o t h e gas chromatographic measurement of kerosene in blood and from t h e m e a s urement of 0.2 microgram of free Cortisol in plasma t o the toxicological evaluation of a p a t i e n t in coma. A wide v a r i e t y of techniques and instruments are used to solve analytical problems rapidly. Analytical results m a y affect critical clinical decisions. T h e handling of a vast a m o u n t of analytical d a t a is now being approached by the development of instruments which provide a "direct r e a d o u t " of concentration. One of t h e direct r e a d o u t instruments recently d e veloped in t h e Clinical Chemistry L a b o r a t o r y is a n electrophoresis densitometer, which gives a direct readout of the weight a n d percentage of each of 5 proteins in a mixture. T h e voltage o u t p u t of these direct readout instruments is linear with concentration a n d in t h e future will be fed into a digital computer for further d a t a processing, storage, a n d retrieval. T h e Clinical Chemistry L a b o r a t o r y has a program of microchemistry which uses for analysis 0.1. ml. of body
fluids starting with a n automatic pipet a n d ending with a direct r e a d o u t instrument. Accuracy, speed of analysis, and small sample size are stressed in t h a t order. About 10 analytical procedures m u s t be available on a 24-hour basis to handle emergencies which come t o a large general hospital. T h e 10 procedures a r e : sodium a n d potassium b y flame photometry, chloride with a chloridimeter, bicarbonate by a microvolumetric method, urea by a colorimetric method, glucose by a colorimetric method, barbiturates b y differential spectrophotometry, amylase b y a n enzymatic method, carbon monoxide b y a spectrophotometric method, a n d porphyrin b y a fluorometric procedure. E v e r y bench has a complete analytical unit,—i.e., for sodium and potassium, iron, glucose, Cortisol, and t h e other determinations done in the laboratory. T h e design is to m a i n t a i n a large open laboratory with cubicles opening into the laboratory. I n s t r u m e n t s are designed or modified for a single purpose a n d placed where t h e analysis is done. T h e major large instruments, such as the recording spectrophotometer, spectrofluorometer, and atomic absorption spectrometer, a r e located centrally where they can be seen and used. Rooms adjacent t o the m a i n laboratory are used for contamination-free purposes and special research p r o j ects. One current research proj ect concerns the isolation and identification of compounds which circulate in t h e body fluids of uremic persons a n d contribute t o their signs a n d symptoms. T h e laboratory work provides the excitement and interest which surrounds a hospital l a b oratory dealing with young physicians caring for sick a n d sometimes unusual patients. VOL. 36, NO. 4, APRIL 1964
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L A B O R A T O R Y OF THE M O N T H Layout of the Clinical Chemistry Laboratory of the Yale-New Haven Medical Center provides desks at the end of work benches. A large aisle allows movement of heavy traffic,
and the general laboratory design eases communication. A folding table (and table cloth) placed in this area serves for on-the-spot biweekly luncheon conferences and seminars
System for measuring protein-bound iodine provides for separation by continuous dialysis of 4 0 samples (board of siphons in the upper left corner), ashing, and photometry. The kinetics are monitored by the digital clock (center) and the measurement is carried out in a servo operated photometer. Measurement of 25 nanograms has an error of less than 1 and is made about 500 times per month Colorimeter, which was designed and partially constructed in the Clinical Chemistry Laboratory, provides a direct readout of concentration of total protein and albumin in serum
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ANALYTICAL CHEMISTRY
WACO POWER STIRRER
HIGH TORQUE FOR C O N T I N U O U S 24 HOUR SERVICE Automatic pipet measures 0.1 ml. of blood for glucose analysis and dilutes it to a final volume of 2.00 ml. with barium hydroxide solu tion. This instrument, de signed and partially con structed in the laboratory, has been found to be more economical and to have less down time than commercial instruments. It is used to pipet and dilute about 8 0 0 0 samples per month
Atomic absorption spectrometer ac curately measures calcium and magnesium in serum. The instru ment attachment on top of the monochromator gives a direct read out of concentration so that a sam ple of serum taken into an auto matic pipet and read in the instru ment could be analyzed from start to finish in 3 0 seconds Flame photometer provides direct readouts of sodium and potassium. On the left is an automatic pipet used to measure 80 microliters of serum and dilute it 200 times with a lithium reagent. The sample is aspirated into the flame (center), and the final concentrations are read (right). The entire analysis from sample to result takes 3 0 seconds
$OQ50 ONLY... ΔΌ No other stirrer made will give as m u c h service per dollar. Use the WACO Pow er Stirrer 2 4 hours a day, 7 days a week for m o n t h s at a t i m e . . . not a stock m o t o r converted to a stirrer, b u t a sparkless i n d u c t i o n type m o t o r spe cifically designed for laboratories . . . where long, continuous use is r e q u i r e d . Two shaft speeds, 3 0 0 and 6 0 0 R.P.M., cover the m a j o r i t y of applications. A built-in cooling fan allows contin uous operation w i t h o u t overheating or b u r n i n g out. 8 6 1 0 0 — W A C O Power Stirrer, w i t h t u bular brass m o u n t i n g rod and 6 f o o t cord . . . only $ 2 9 . 5 0 . Stirrer chucks, $ 1 . 8 5 ea., set of t h r e e s t i r r i n g rods ( s m a l l , m e d i u m , large), $ 8 . 0 0 . Order direct or write for descriptive folder. LABORATORY SUPPLIES A N D EQUIPMENT
WILKENS-ANDERSON 4525 W . D I V I S I O N ST.
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Circle Ne. 99 on Readers' Service Card
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