Reagent Strips for Urinalysis.
Ascorbic Acid (vitamin C)
For In Vitro Measurement of Urine Vitamin C
Store at temperatures between 15°-30°C (59°-86°F)
Keep away from sunlight
Replace cap immediately and tightly
Do not remove desiccant from bottle
Read enclosed directions carefully
Do not use after expiration date.
Do not touch test area of strip. Remove only enough strips for immediate use. Keep out of reach of children.
Directions must be followed exactly:
1. Dip reagent strip in freshly collected urine and remove immediately or alternatvely wet the reagent strip by passing through the urine stream.
2. While removing, run the edge of the strip against the rim of the urine collection cup to remove excess urine.
3. 30 seconds after removing from urine, compare reagent side of test area with corresponding color chart.
URS-1A reagent strips provide a fast, convenient way of screening for Vitamin C (ascorbic acid) in urine. Vitamin C found in the urine test provides information regarding the status of Vitamin C absorption and consumption. This test is based on the action of a complex chelating agent with a polyvalent metal ion in its higher state and an indicator dye that can react with the metal ion in its lower state to produce a color change from blue-green to yellow. The colors range from blue-green for a ‘negative’ reading to yellow for a ‘positive’ reading.
URS-1A strips for urinalysis are firm plastic strips to which Vitamin C reagent areas are affixed. URS-1A strips are packaged along with a drying agent in a plastic bottle. Each strip is ready to use upon removal from the pouch. The entire reagent strip is disposable. Results are obtained by direct comparison of the test strip with the color blocks printed on the color chart.
Warnings and Precautions
1) Urine strips are for in vitro diagnostic use only. They have been determined to be nonhazardous under the guidelines issues by OSHA in 29 CFR 1910.1200 (d)
2) Any visual impairment, such as color blindness, will affect accuracy of reading the results.
3) To obtain best results, use fresh urine.
4) Follow directions exactly.
5) For optimal results, accurate timing is essential.
6) Exposure of URS-1A to light, moisture, or heat will cause deterioration and decrease reactivity.
Conditions under which the device should and should not be used.
1) Comparison to the color chart is dependent on the interpretation of the individual. It is therefore recommended that all users be tested for color blindness.
2) Work areas and specimen containers should be free of contaminating substances.
3) When testing, dip test areas of urine completely, but briefly to avoid dissolving out the reagents. Read test results carefully at specified time in a good light with the rest area held near the color chart.
Work areas and specimen containers should be free of contaminating substances. Collect urine in a clean container and test as soon as possible. Collect urine in a clean container and test as soon as possible. If testing cannot be performed within one hour, refrigerate the specimen immediately. Allow refrigerated specimen to return to room temperature before testing.
Reading the results
When a strip is dipped in urine, the test area changes color according to the amount of Vitamin C present in the urine. The developing color of the test area is compared to the color blocks on the color chart after time specified.
Store at room temperature between 15°-30°C (59°-86°F) and out of direct sunlight. Do not use after expiration date.
1) Remove from the bottle only enough strips for immediate use and twist the cap back tightly.
2) Completely immerse reagent areas of the strip in fresh, well-mixed urine. Remove the strip immediately to avoid dissolving out the reagent areas.
3) While removing, touch the side of the strip against the rim of the urine container to remove excess urine. Blot the lengthwise edge of the strip on an absorbent paper towel to further remove excess urine and avoid running over (contamination from adjacent reagent pads).
4) After 60 seconds, compare the reagent pad to the color block on the color chart and read at the times specified. Proper read time is critical for optimal results.
5) Obtain results by direct color chart comparison.
Results with URS-1A are obtained by direct comparison of the color blocks printed on the color charts. The color blocks represent nominal values; actual values will vary round the nominal values.
Limitations of procedure
As with all laboratory tests, definitive diagnostic or therapeutic decisions should not be based on any single test result or method.
This test can detect ascorbic acid in concentrations as low as 10mg/dl in urine.
The daily urinary output of ascorbic acid varies with the intake: it approximately half of the intake. The average urinary output ranges from 2030 mg/day. If detect ascorbic acid in urine, stop taking ascorbic acid for 24 hours and retest.
False negative and weak reaction of glucose, blood and bilirubin may be observed if:
Glucose: more than 50mg/dl ascorbic acid in the sample
Bibirubin: more than 50mg/dl ascorbic acid in the sample
Blood: more than 10mg/dl ascorbic acid in the sample.