The sensitivity of the Multi-drug InstaStrip Test is set as required for the screening immunoassays of these drugs in the reference guidelines set by the National Institute on Drug Abuse (NIDA) and the U.S. Department of Health and Human Services.

Principle of the test

The Multi-drug InstaStrip Test is a competitive binding immunoassay in which drug and drug metabolites in a urine sample compete with immobilized drug conjugate for limited labeled antibody binding sites.  By utilizing antibodies that are specific to different drug classes, the test permits independent, simultaneous detection of three drugs from a single sample. The approximate run time is 5 minutes.

In the assay procedure, urine mixes with labeled antibody-dye conjugate and migrates along a porous membrane. When the concentration of a given drug is below the detection limit of the test, unbound antibody-dye conjugate binds to antigen conjugate immobilized on the membrane, producing a rose-pink color band in the appropriate Test Zone for that drug. Conversely, when the drug level is at or above the detection limit, free drug competes with the immobilized antigen conjugate on the membrane by binding to antibody-dye conjugate, forming an antigen- antibody complex, preventing the development of a rose-pink color band.

Regardless of the drug levels in the sample, a rose-pink color band is produced in each Control Zone (marked “C”) by a parallel immunochemical reaction.  These bands serve as built-in quality control measures by demonstrating antibody recognition, verifying that the reagents are chemically active.

Reagents and materials provided

1.     Test Devices.                            Contains dye-conjugated  antibody and immobilized antigen in protein matrix with sodium azide.

Optional:
 

Materials required but not provided

1.     Clock or timer.

2.     Specimen collection containers. 

WARNINGS AND PRECAUTIONS

1.     For in vitro diagnostic and professional use only.

2.     Do not use the test device beyond the expiration date.

3.     Urine specimens may be infectious; properly handle and dispose of all used reaction devices in a biohazard container.

4.        Visually inspect the foil package to insure it is intact.  If the package is not intact, the integrity of the device might be compromised.

Storage and and stability

Store test kit below 28°C; do not freeze.  Refer to the expiration date for stability.

Test procedure

1.     Bring a urine sample and a foil test pouch to room temperature (15°-28°C).

2.     Do not break the seal of the pouch until ready to begin testing.

3.     Remove a Test Device from the foil pouch.

4.     Remove the protective cap and place the revealed strips into the urine sample for 10 seconds. Do not allow the urine level to touch the plastic device.

Note: The result must be interpreted at five minutes. Waiting more than five minutes may cause the reading to be inaccurate. To avoid confusion, discard the test device after interpreting the result.

 
Positive:  A rose-pink band is visible in each control zone. No color band appearing in the appropriate test zone indicates a positive result for the corresponding drug of that specific test zone.

Negative:  A rose-pink band is visible in each control zone and the appropriate test zone, indicating that the concentration of the corresponding drug of that specific test zone is below the detection limit of the test.

Invalid:  If a color band is not visible in each of the control zones, the test is invalid. Another test should be run to re-evaluate the specimen.

Note: There is no meaning attributed to line color intensity or width.

Quality control

An internal procedure control has been incorporated into the test to ensure proper kit performance and reliability.

The use of an external control is recommended to verify proper kit performance. Quality control samples should be tested according to quality control requirements established by the testing laboratory.

Limitations of the test

1.  This product is designed to be used for the detection of drugs of abuse and their metabolites in human urine only.

2.  Although the test is very accurate, there is the possibility false results will occur due to the presence of interfering substances in the specimen sample.

3.  The test is a qualitative screening assay and is not suggested for quantitative determination of drug levels in urine, or the level of intoxication.

4.  Adulterants such as bleach or other strong oxidizing agents, when added to urine specimens can cause erroneous test results regardless of the analysis method used.  If adulteration is suspected, obtain another urine specimen.

Performance characteristics

1.        Sensitivity.  The Multi-drug InstaStrip Testdetects drugs of abuse and their major metabolites in urine at concentrations equal to or greater than the cut-off level for the specific drug, which is suggested by the National Institute on Drug Abuse (NIDA) for the immunoassay method.

2.        Specificity.  A study was conducted with the Multi-drug InstaStrip Test to determine the cross-reactivity of drug-related compounds with the test.  Substances listed in Table I produced results approximately equivalent to the cutoff levels. A separate study was conducted to determine the cross-reactivity of non-related compounds with the test at concentrations much higher than normally found in the urine of people using or abusing them. No cross reactivity was detected with the substances listed in Table II.

Table I: Concentrations of drug-related compounds showing positive response approximately equivalent to the cut-off set for the test:

The following Cocaine-related substances yield positive results for Cocaine:

Benzoylecgonine                         300 ng/ml

Cocaine                                          300 ng/ml

Isoxsurpine                                1,500 ng/ml