Principle
The TRUST reagent containing modified VDRL antigen and toludine red pigment particles, flocclulate when mixed with sample containing “reagin”.
A reactive specimen is
indicated by macroscopically visible red clumps against white background, in
contrast nonreactive specimen appear to have slightly rough light red
background. This test is a screening test and if positive, further testing with
specific confirmatory tests are required.
Specimen:
Serum/Plasma
Requirement
- TURST Antigen
suspension
- Positive Control
Serum
- Negative Control
Serum
- Disposable
Plastic Cards
- Disposable
Plastic Droppers
- Disposable
Applicator Sticks
- Antigen Delivery
Dropper
- Rubber Teats
Procedure
QUALITATIVE TEST
- Using disposable
serum dropper, place one free falling drop of serum / plasma or control on the
entire circle with the help of disposable applicator stick.
- Gently shake the
TRUST Antigen Suspension bottle to resuspend the particle. From the dropper
dispense few drops of the reagent back into the reagent bottle itself to remove
air trapped to the dropper.
- Add one free
falling drop of TRUST Antigen Suspension using antigen delivery dropper. Keep
the delivery dropper vartical, exactly at 90o while adding antigen suspension.
Do not mix.
- Place the card on
the mechanical rotator under humidifying cover and rotate the card for 8
minutes at 100 ±2 rpm.
- After 8 minutes,
immediately remove the card from the rotator, rotate and till the card gently
by hand. 6) Observe the result under a high intensity lamp or strong day
light.
- Perform the
quantitative test for specimens exhibiting any degree of flocculation or
“roughness”.
SEMI-QUANTITATIVE TEST
- Place 50μL of
0.9% saline solution on 2nd, 3rd, 4th and 5th circles of the card by using
micropipette. Do not spread the saline solution.
- Using
micropipette, add 50μL sample to saline in 1st and 2nd circle.
- Mix sample with
saline in 2nd circle by drawing the mixture up and down for 8 times in the
micropipette. Avoid bubble formation.
- Aspirate 50μL
from 2nd circle and transfer to 3rd circle. Repeat the same successively up to
5th circle.
- Aspirate 50μL
from the 5th circle and discard it.
- Repeat step no.2-6
of qualitative test for each of diluted sample drop.
- Complete test as
described in qualitative test procedure. Use a clean tip for each specimen
tested.
- Prepare higher dilution if necessary in 1:50 nonreactive serum dilution.
- The end point is the highest dilution showing visible black clumps.
Observation table of TRUST test:
QUALITATIVE TEST
SEMI-QUANTITATIVE TEST
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