(60 days)
Immunoassay for the in vitro quantitative determination of estradiol in human serum and plasma.
Competition principle. Total duration of assay: 18 minutes, 37 °C.
· 1st incubation (9 minutes): By incubating the sample (50 uL) with an estradiol-specific biotinylated antibody (65 uL), an immunocomplex is formed, the amount of which is dependent upon the analyte concentration in the sample.
·2nd incubation (9 minutes): After addition of streptavidin-coated microparticles (35 µL) and an estradiol derivative labeled with a ruthenium complex* (65 uL), the still-vacant sites of the biotinylated antibodies become occupied, with the formation of an antibody-hapten complex. The entire complex becomes bound to the solid phase via interaction of biotin and streptavidin.
· The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Unbound substances are then removed with ProCell. Application of a voltage to the electrode then induces chemiluminescent emission which is measured by a photomultiplier (0.4 second read frame).
·Results are determined via a calibration curve which is instrumentspecifically generated by 2-point calibration and a master curve provided via the reagent bar code.
** Tris(2,2'-bipyridy))ruthenium(II) complex (Ru(bpy)" 3)
The provided text describes a 510(k) summary for the Boehringer Mannheim Elecsys® Estradiol Assay, comparing it to a predicate device, the Enzymun-Test® Estradiol Assay (K916132). This submission focuses on establishing substantial equivalence based on performance characteristics.
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state formal "acceptance criteria" with pass/fail thresholds. Instead, it presents performance characteristics of the new device (Elecsys® Estradiol) and directly compares them to the predicate device (Enzymun-Test® Estradiol). The implicit acceptance criterion is that the performance of the Elecsys® Estradiol Assay is comparable to or better than the predicate device.
Given this, I will construct a table comparing the performance of the Elecsys® Estradiol Assay with the Enzymun-Test® Estradiol Assay, as this constitutes the 'reported device performance' against an implicit 'acceptance' of being equivalent to the predicate.
| Feature | Elecsys® Estradiol Performance | Enzymun® Estradiol Performance (Predicate) | Implicit Acceptance Criteria (Comparison to Predicate) |
|---|---|---|---|
| Precision | Comparable precision (within-run and total) | ||
| Within-Run (Mean) | Low: 7.7, Mid: 44.0, High: 277.6, High: 1217.0 (pg/mL) | Low: 8.2, Mid: 53.3, High: 3021 (pg/mL) (Note: Different levels reported for Elecsys vs. Enzymun) | - |
| Within-Run (%CV) | Low: 3.0, Mid: 2.7, High: 3.3, High: 2.7 (Note: Different levels reported for Elecsys vs. Enzymun) | Low: 14.3, Mid: 16.1, High: 9.1 | - |
| Total (Mean) | Low: 9.0, Mid: 44.0, High: 277.6, High: 1217.0 (pg/mL) | Low: 10.3, Mid: 53.3, High: 3021 (pg/mL) | - |
| Total (%CV) | Low: 9.0, Mid: 9.0, High: 10.0, High: 10.0 (Note: Different levels reported for Elecsys vs. Enzymun) | Low: 16.1, Mid: 16.1, High: 10.3 | - |
| Lower Detection Limit | 10 pg/mL | 10 pg/mL | Equal or lower detection limit |
| Linearity | 10-4600 pg/mL (with a deviation from a linear line of ±10%) | 10-1300 pg/mL (with a deviation from a linear line of ±10%) | Comparable linearity range, potentially wider |
| Method Comparison (Vs Enzymun-Test Estradiol) | High correlation (r value > 0.97) and small bias | ||
| Least Squares | y = 1.027x + 6.32; r = 0.995; SEE = 31.03; N = 64 | y = 0.902x + 42.94; r = 0.976; SEE = 91.96; N = 74 | - |
| Passing/Bablok | - | y = 0.962x + 12.51; r = 0.976; SEE = 38.71; N = 74 | - |
| Interfering Substances (No interference at) | Bilirubin: 64.5 mg/dL; Hemoglobin: 1.0 g/dL; Lipemia: 1250 mg/dL; Biotin: 20 ng/mL | Bilirubin: 25 mg/dL; Hemoglobin: 200 mg/dL; Lipemia: 1500 mg/dL; Biotin: 24 ng/mL | Comparable or improved resistance to interference |
| Specificity (% Cross-reactivity) | Low cross-reactivity, comparable to predicate or better | ||
| 17 hydroxy-Progesterone |
§ 862.1260 Estradiol test system.
(a)
Identification. An estradiol test system is a device intended to measure estradiol, an estrogenic steroid, in plasma. Estradiol measurements are used in the diagnosis and treatment of various hormonal sexual disorders and in assessing placental function in complicated pregnancy.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 862.9.