RIDASCREEN Stuhlröhrchen

Transcription

1 RIDASCREEN Stuhlröhrchen Accessory for RIDASCREEN Calprotectin Art. No. GZ3006 R-Biopharm AG, An der neuen Bergstraße 17, D Darmstadt, Germany Tel.: +49 (0) / Telefax: +49 (0)

2 1. Intended use RIDACSCREEN Stuhlröhrchen is used for the sampling and the homogenization of human stool samples in the laboratory. They are accessories for the RIDASCREEN Calprotectin ELISA assay G Kit content One kit contains 48 stool sampling tubes. 3. Description of stool sampling tube One RIDASCREEN Stuhlröhrchen is composed of the following parts: - tube - screw cap (orange) - measuring stick with measuring tip 4. Storage The stool collection tubes need to be stored at 2 8 C. 5. Necessary equipment Vortex, inoculation loop or wooden stick 2

3 6. Warning/ precautions The stool collection tubes should not be centrifuged. Stool samples should be treated as potentially infectious material. 7. Collection and storage of samples Stool samples should be shipped cooled if possible and stored at 2 8 C. If the analysis will not start immediately after arrival of the samples (within 3 days), storage at -20 C or colder is recommended. Repeated freezing and thawing of samples should be avoided. 7.1 Liquid stool Liquid stool samples should be avoided. If this is not possible we recommend to pipet 10 µl of the liquid stool sample directly into the buffer of the stool collection tube. To do this, please open the tube at the grey lid. 7.2 Very solid stool Very solid stool should be thoroughly homogenized before transfer into the stool collection tube, e.g. by using a wooden stick or inoculation loop. When vortexing the tube make sure that the stool is completely washed out from the grooves of the measuring tip. 8. Sample preparations The stool sample should be at room temperature (20 25 C) before extraction and should be homogenized e.g. with an inoculation loop or a wooden stick. When transferred to the stool collection tube it should be taken care, that the grooves of the measuring tip are completely filled with stool. Moreover, no stool should be at the bar of the measuring stick. 3

4 9. Collecting samples with sample collection device instruction for use 1. Unscrew the measuring stick (orange cap) anti-clockwise. 2. Remove the stick with the measuring tip. 3. Dip the measuring tip into the stool specimen at three different places. 4. Make sure that the grooves of the measuring tip are filled with stool. 5. Return the stick into the tube. By inserting the stick into the tube, excess stool material remains in the funnel insert. Close the tube carefully by screwing the cap clockwise. The measuring tip collects about 10 mg of stool sample. For liquid stool samples 10 µl of stool sample can be measured and pipetted directly into the extraction buffer. 6. Vortex the tube until the stool sample from the measuring tip is fully suspended in extraction buffer. 7. Incubate the stool collection tubes with the orange cap facing downwards for 15 minutes at room temperature. This ensures that all particles sedimented and the foam, that can develop during vortexing, has set. RIDASCREEN Stuhlröhrchen should not be centrifuged. Stability of the suspension: (see 9.0 Storage of extracts). 8. For testing, open the tube at the grey cap. The suspended stool sample can now be diluted for testing. Dilute 100 µl of the stool suspension in 900 µl RIDASCREEN sample dilution buffer (Diluent 3). 100 µl of the previously diluted stool sample (1:10) can be used directly in the assay. Note: The RIDASCREEN Stuhlröhrchen can also be used on automated 4-plate ELISA-Readers, e.g. Dynex DSX. Sedimentation time of 15 minutes can help to avoid possible difficulties with dispension. 10. Storage of extracts The calprotectin concentrations in the extraction buffer of the RIDASCREEN Stuhlröhrchen (GZ3006) are not always stable for 7 days at 4 C in every stool sample. For this reason it is recommended to use the fresh extract immediately in the test. However the majority of analyzed stool extracts of the RIDASCREEN Stuhlröhrchen (GZ3006) showed a stabile calprotectin concentration for a period of at least 3 days. Only 3 out of 78 samples (3.8 %) showed a significant increase in calprotectin concentration. 1 out of 78 samples (1.3 %) showed a significant decrease in calprotectin concentration. None of the analyzed samples, which showed a calprotectin concentration well below the cut off of 50 mg/kg and were tested as negative, became distinctly positive after storage of 7 days. 4

5 11. Precision of RIDASCREEN Stuhlröhrchen 39 stool samples in a concentration range of to mg/kg were tested with RIDASCREEN Calprotectin. The stool volume was collected either, as described in the IFU by weighing or through sampling by RIDASCREEN Stuhlröhrchen. The concentrations were determined for both methods and the correlation coefficient (r) of r = 0.99 was calculated (see figure 1). Figure 1: Correlation of Calprotectin concentrations after sampling by RIDASCREEN Stuhlröhrchen or by weighing. The correlation coefficient is r = The correlation coefficient of 0.99 shows the high comparability of the results of weighing versus RIDASCREEN Stuhlröhrchen. 5