(51 days)
Immunoassay for the in vitro quantitative determination of digoxin in human serum and plasma for the in vitro diagnosis and treatment of digoxin overdose and in monitoring levels of digoxin to ensure proper therapy.
The electrochemiluminescence immunoassay "ECLIA" is intended for use on the Boehringer Mannheim Elecsys 2010 immunoassay analyzer.
Competition principle. Total duration of assay: 18 minutes, 37 ℃. · 1st incubation (9 minutes): By incubating the sample (10 µL) with a digoxinspecific ruthenylated** antibody (80 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 (30 uL) and a digoxin derivative labeled with biotin (80 uL), the still-vacant sites of the ruthenylated 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'-bipyridyl)ruthenium(II) complex (Ru(bpy)2+3)
The Boehringer Mannheim Elecsys® Digoxin Assay is an in vitro quantitative immunoassay for digoxin in human serum and plasma, used for diagnosing and treating digoxin overdose and monitoring digoxin levels for proper therapy. It is intended for use on the Boehringer Mannheim Elecsys 2010 immunoassay analyzer.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Elecsys® Digoxin Assay are implicitly established through comparison with the predicate device, the Abbott TDx® Digoxin II Assay. The study aimed to demonstrate substantial equivalence, meaning the performance of the Elecsys® Digoxin Assay should be comparable or improved relative to the predicate device across various performance characteristics.
| Feature | Acceptance Criteria (Implied by Predicate) | Elecsys® Digoxin Performance |
|---|---|---|
| Precision | Comparable to Abbott TDx® Digoxin II Assay (e.g., %CV ranges for within-run and total precision) | Within-run %CV: |
| Level 1: 3.57 | ||
| Level 2: 3.33 | ||
| Pool 1: 5.22 | ||
| Total %CV: | ||
| Level 1: 5.24 | ||
| Level 2: 4.09 | ||
| Pool 1: 7.69 | ||
| (Note: This is compared to TDx within-run %CV of 0.70-3.66 and total %CV of 1.91-7.67 across different levels) | ||
| Lower Detection Limit | Not explicitly stated, but predicate has 0.2 ng/mL. Implies a comparable or lower limit. | 0.15 ng/mL (Better than predicate) |
| Linearity | Comparable to predicate (0.0 - 5.0 ng/mL) | 0.15 - 5 ng/mL (Comparable to predicate) |
| Method Comparison | Good correlation with predicate device (Abbott TDx® Digoxin II). High correlation coefficient (r) and appropriate slope/intercept values. | Vs Abbott TDx Digoxin: |
| Least Squares: y = 1.03X + 0.10, r=0.9847, N=357 | ||
| Passing Bablock: y = 1.06X + 0.06, r=0.9847, N=357 | ||
| Interfering Substances | Demonstrate no significant interference from common substances at clinically relevant concentrations, comparable to predicate levels. | No interference at: |
| Bilirubin: 65 mg/dL (Predicate: 20 mg/dL) | ||
| Hemoglobin: 1000 mg/dL (Predicate: 1000 mg/dL) | ||
| Lipemia: 1500 mg/dL (Predicate: 2500 mg/dL) | ||
| Rheumatoid Factor: 1630 IU/mL (Predicate: N/A) | ||
| Biotin: 100 ng/mL (Predicate: N/A) | ||
| Specificity | Demonstrate low cross-reactivity with structurally similar compounds and other relevant substances, comparable to predicate. | % Cross-reactivity: |
| Digoxigenin: 14.28 (Predicate: up to 200) | ||
| Digoxingenin-Mono-Digitoxiside: 55.31 (Predicate: up to 200) | ||
| Digitoxin-Bis-Digitoxiside: 74.64 (Predicate: up to 200) | ||
| Digitoxin: 1.13 (Predicate: 4.8) | ||
| Cortisol: |
§ 862.3320 Digoxin test system.
(a)
Identification. A digoxin test system is a device intended to measure digoxin, a cardiovascular drug, in serum and plasma. Measurements obtained by this device are used in the diagnosis and treatment of digoxin overdose and in monitoring levels of digoxin to ensure appropriate therapy.(b)
Classification. Class II.