positive safety, perfect performance
REPORT FOR MANAGEMENT
lasting quality... plus economy
iNALGONVAEXfttt^PLASTIC TU«ING N e w , yes! . . . but it has proven its superiority in every plastic tubing requirement . . . and
with
greater economy! M a n y outstanding
laboratories
already
have
turned to N a l g o n , judging it on its quality, not on its lower price It has complete neutrality, absolute flexibility, clear water-white transparency. It is chemically resistant; acid, alkali resistant; non ,y f.f
oxidizing. Actual laboratory tests proved its safety, dependability,
Ask for
convenience in every operation re-
a
quiring SUPERIOR plastic tubing.
own At your favorite Laboratory or write direct to
The
Supply
sample;
m a k e your tests!
Dealer
NALGE CO., Inc. R O C H E S T E R 2 , N E W YORK
For further information, circle number 18 A-1 on Readers' Service Card, page 55 A
ÛMUH
RIPLE BEAM
BALANCE
record which details the character of the lot. Subsequently the finished product is retested for potency and far more extensively than when in process. This task falls within the province of the microbiological quality control group, which is divided into four test sections: bioassay, sterility, environmental, and pharmacological. Pfizer uses bioassay methods to support its chemical tests. Though more costly, they are required because chemical tests, of themselves, are not specific enough to establish biological activity and this is a factor that must be very carefully checked before the drugs can be released for shipment. A few antibiotics, in fact, cannot be satisfactorily tested by chemical means at all and these are checked entirety by microbiological assay. Apart from sterility tests on the finished product, the microbiological group at regular intervals also runs tests to ascertain that all sterile work areas are sterile in fact as well as designation. It periodically assays warehouse inventory to make sure that there has been no deterioration in the quality of the stored products and also tests finished dosage forms for toxicity in mice, pjTOgens in rabbits, and depressors—such as histamines—in cats. And in the case of some customer complaints on products, the microbiological group re-examines returned material. From its observations on these "rejects," the group sometimes gathers information, which when correlated with other data, can make for an improved product. Stability
widest selection
BEAM
CALIBRATIONS
SCALE
CAPAC7!
·
greatest capacity
MODEL 7 5 0 - S with metric calibrations
for vontptetv intttvmntittn trrite for fyrorhtirt'
OHAUS
SCALE
CORPORATION
lOSO COMMERCE AVE. UNION, NEW JERSEY
For further information, circle number 18 A-2 on Readers' Service Card, page 55 A
18 A
No product is really approved unless it is practically stable, however, and Pfizer tests for stability not only in process, finished product, and dosage form but also under accelerated conditions. This is necessary because many of the antibiotics and vitamins, to a lesser degree, are unstable and can go downhill rapidly. Meticulous testing ensures both company and customer that a given dosage form will live up to its specifications under a wide variety of climatological conditions all over the world, sometimes for as long as 3 to 5 years after it has gone into distribution. And in making its stability tests, Pfizer must consider not only the steaming humidity of Panama, say, but also far less predictable vagaries of the druggist who might inadvertently store his antibiotics just a little too close to a hot radiator, or where the sun can get at them. Consequently, the working equation is a complex one and is made even more so by a myriad of possible combinations. ANALYTICAL
CHEMISTRY
