| TES-TAPEŽ Lilly Glucose Enzymatic Test Strip Diagnostic Aid
Tes-Tape is impregnated with the enzymes glucose oxidase and peroxidase and an oxidizable substrate, orthotolidine. When the tape is dipped into urine containing glucose, the glucose oxidase catalyzes the reaction of glucose in the urine with oxygen from the air to form gluconic acid and hydrogen peroxide. The enzyme peroxidase (from horseradish) then catalyzes the reaction of hydrogen peroxide and orthotolidine to form a blue color. With the addition of a yellow dye (FDC Yellow No. 5) to the paper, the possible color range of the test is extended from yellow to light green to deep blue. If no glucose is present, the tape maintains its yellow color. See Table I.
Reactive Ingredients Approximate Amount per 4 cm of Tape
Glucose oxidase 3.78 units
Horseradish peroxidase 2.82 PZ units
o-tolidine 0.136 mg
Nonreactive ingredients include filter paper, FDC Yellow No. 5 coloring, buffers, stabilizers, and wetting agents.
Indications And Clinical Uses :
For in vitro diagnostic use in testing for the presence of glucose in human urine.:
Do not use if the tape turns dark yellow or brown or if, after being tested in distilled water, it does not match the negative color bar.:
The urine should be fresh, collected in a container free of chemicals and glucose, and clear in appearance.
If the freshly voided specimen is not to be tested within 4 hours, it should be refrigerated or preserved in up to 0.37 % formaldehyde.
Drugs that are known to have an inhibitory effect on the enzyme reactions include ascorbic acid (vitamin C), dipyrone, gentisic acid (a metabolite of ASA), homogentisic acid (present in alkaptonuria), levodopa, meralluride injection and methyldopa. The inhibiting effect is notable on the dipped part of the tape, but accurate readings may be obtained by observing the narrow band of color at the junction of the dry and wet portions. A separation of glucose from the inhibitory substances occurs as the urine travels along the dry portion of the tape. Ingestion of more than 1.5 g of ascorbic acid may produce urine with inhibitory action on Tes-Tape.
Specimens for storage or shipment should be refrigerated or preserved with up to 0.37 % formaldehyde.
All materials are provided for the test and include dispenser, tape and color chart.
Results on the color chart are expressed as positive or negative.
After dipping Tes-Tape into urine, do not place it on the lavatory or on paper. Small amounts of glucose in paper or perspiration will affect the test.
Patients who are receiving high doses of ascorbic acid or whose urine contains dipyrone, meralluride, homogentisic acid, gentisic acid, levodopa or methyldopa should read only the very narrow band of color in the moist part of the tape above the level to which it was dipped into the specimen.
Very high doses of ascorbic acid may cause a false negative test even with the above precaution. (Urinary levels of ascorbic acid in excess of 0.1% are necessary to block the test completely. This concentration is most likely to appear within 3 to 7 hours after a single dose of 1.5 g or more.)
Normal urine should test negative with Tes-Tape. Persons using Tes-Tape for a screening test should report all positive readings to their physician. The color chart provided is based on the average color perception of many observers. Patients who have difficulty in differentiating color should seek the advice of their physician before using Tes-Tape.
Numerous other clinical and laboratory studies have shown that Tes-Tape is accurate in qualitative determinations of urine sugar. Tes-Tape is specific for glucose in urine sugar testing. Except for instances involving contamination of the tape or urine receptacle with glucose from other sources (e.g., perspiration, tears, and saliva) or with a residue of chlorine from cleansing agents, there is no known clinical situation in which a false-positive test for glucose occurs with Tes-Tape. The sensitivity of Tes-Tape is such that it will react with concentrations of 0.05 % glucose or more. Trace reactions shown by the development of a very light yellow-green color may be observed with less than this amount of glucose.
Directions: See package insert.
Availability And Storage:
Individual dispenser packages of approximately 100 tests. Materials included for tests include dispenser, tape and color chart. Store at controlled room temperature, 15 to 30°C. Protect from high humidity and light.