(315 days)
The AspirinWorks® Test Kit is an enzyme-linked immunoassay (ELISA) to determine levels of 11-Dehydro Thromboxane B2 (11dhTxB2) in human urine, which aids in the qualitative detection of aspirin effect in apparently healthy individuals post ingestion. For professional use only. The AspirinWorks® Test Kit is intended for use in clinical (hospital and reference) laboratories.
An ELISA for the detection of urinary 11-Dehydro Thromboxane B2 (11dhTxB2). Goat anti-mouse IgG polyclonal antibody (Jackson ImmunoResearch Laboratories, Inc, West Grove, PA) is coated onto 96microwell plates. Reference, control, and patient samples are diluted in a Tris-based sample diluent (pH 9.0) and added to the microwells. An 11dhTxB2 tracer (11dhTxB2 linked to alkaline phosphatase, (AP); Cayman Chemical Company, Ann Arbor, MI) is then added to all wells except assay blanks, followed by the addition of an anti-11dhTxB2 murine monoclonal antibody (Cayman Chemical Company) to all wells except assay blanks. The maximum binding wells (Bo) contain sample diluent, tracer, and monoclonal antibody, but no unlabeled 11dhTxB2. The plate is then covered with the plastic sheet provided in the kit, and incubated at room temperature on a rotary shaker at 300-600 pm for two hours. The AP-Tracer and unlabeled 11dhTxB2 from the reference curve/controls/samples compete for binding to the anti-11dhTxB2 monoclonal antibody, which is bound to the plate by the goat anti-mouse polyclonal antibody. After incubation, the reaction solution is removed from the wells followed by five washes with TBS/Tween 20. The pNPP substrate is then added and the plate is covered and incubated with shaking for 30 minutes. The reaction is stopped by the addition of Stop Solution (0.1M EDTA) to the wells, and the plate is read at 405-420 mm. Results are compared to the reference curve and expressed in pg/ml. Patient results are then normalized using the creatinine concentration of the sample, as measured by a separate assay.
The Corgenix AspirinWorks® Test Kit is an enzyme-linked immunoassay (ELISA) designed to measure levels of 11-Dehydro Thromboxane B2 (11dhTxB2) in human urine. This measurement aids in the qualitative detection of aspirin effect in apparently healthy individuals post ingestion.
1. Acceptance Criteria and Reported Device Performance:
The document implicitly defines acceptance criteria through the reported performance that demonstrates the device's ability to detect aspirin effect consistently with established literature. While explicit numerical acceptance criteria for sensitivity/specificity against a definitive gold standard are not provided, the "cutoff" value and the agreement with published aspirin non-responsiveness rates serve as the basis for acceptance.
| Criterion | Reported Device Performance |
|---|---|
| Cut-off for aspirin effect | Established at ≤1500 pg 11dhTxB2/mg creatinine. |
| Detection of aspirin-naive individuals | 180/204 (88.2%) of samples from individuals not taking aspirin were above the cutoff value (>1500 pg 11dhTxB2/mg creatinine), indicating a lack of aspirin effect (as expected). |
| Detection of aspirin non-responsiveness | - 7/163 (4.3%) of 81 mg/day aspirin users indicated a lack of aspirin effect (>1500 pg 11dhTxB2/mg creatinine). |
- 4/38 (10.5%) of the 325 mg/day aspirin users indicated a lack of aspirin effect.
- In total, 11/201 (5.5%) of all aspirin users tested indicated a lack of aspirin effect.
- These percentages are reported as "consistent with those in published literature for aspirin non-responsiveness or lack of aspirin effect." |
| Detection Range (Non-clinical) | 300 - 4000 pg/mL |
| Precision (Non-clinical) | Intra- and inter-assay precision %CV's are all
§ 864.5700 Automated platelet aggregation system.
(a)
Identification. An automated platelet aggregation system is a device used to determine changes in platelet shape and platelet aggregation following the addition of an aggregating reagent to a platelet-rich plasma.(b)
Classification. Class II (performance standards).