(72 days)
The Magnesium assay is used for the quantitation of magnesium in human serum, plasma, or urine on the ARCHITECT c8000 System.
Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low plasma levels of magnesium) and hypermagnesemia (abnormally high plasma levels of magnesium).
The Magnesium reagent kit contains Reagent 1 and Reagent 2. Magnesium present in the sample is a cofactor in an enzymatic reaction with isocitrate dehydrogenase. The rate of increase in absorbance at 340 nm, due to the formation of NADPH, is directly proportional to the magnesium concentration.
The provided document is a 510(k) summary for a medical device called "Magnesium" from Abbott Laboratories. It details the performance testing conducted to demonstrate its substantial equivalence to a predicate device. This document describes an in vitro diagnostic (IVD) device for measuring magnesium levels, not an AI/ML-based device. Therefore, many of the requested elements related to AI (e.g., ground truth establishment by experts, adjudication, MRMC studies, training set details) are not applicable to this submission.
However, I can extract information relevant to the acceptance criteria and performance of this IVD device.
Here's the breakdown of the acceptance criteria and study that proves the device meets them, based on the provided text:
Device: Abbott Laboratories Magnesium Assay (List No. 3P68)
Intended Use: Quantitation of magnesium in human serum, plasma, or urine on the ARCHITECT c8000 System for diagnosis and treatment of hypomagnesemia and hypermagnesemia.
Predicate Device: Roche Magnesium Gen.2 (K983416)
1. Acceptance Criteria and Reported Device Performance
The document describes various performance studies and their results. The implicit acceptance criteria are that the device's performance characteristics demonstrate substantial equivalence to the predicate device and are within acceptable ranges for clinical utility.
| Study Type | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Limit of Blank (LoB) | LoB should be low, demonstrating minimal signal in the absence of analyte. (No explicit numerical criterion stated, but values are reported). | Urine application: LoB of 0.04 mg/dL |
| Limit of Detection (LoD) | LoD should be low enough to detect clinically relevant low levels. (No explicit numerical criterion stated, but values are reported). | Urine application: LoD of 0.09 mg/dL |
| Limit of Quantitation (LoQ) | LoQ should be low enough for accurate quantitation at clinically relevant low levels. (No explicit numerical criterion stated, but values are reported). | Urine application: LoQ of 0.75 mg/dL |
| Within-Laboratory Precision (Imprecision) | %CV should be clinically acceptable, demonstrating consistency of results over time. (No explicit numerical criterion stated, but values are reported as evidence of acceptable precision). | Urine (within-laboratory imprecision): |
- Bio-Rad Level 1: 1.3 %CV
- Bio-Rad Level 2: 1.3 %CV
- LoQ Urine Pool -Low Mg: 2.4 %CV
- Human Urine Pool - Normal Mg: 1.8 %CV
- Human Urine Pool Abnormal Mg: 1.8 %CV |
| Interference | Assay results should be impacted by no more than ±10% for specific interferent levels. | For magnesium samples targeted to 5 mg/dL: no more than ±10% interference for listed substances (Albumin ≤ 64.0 mg/dL, Ascorbic Acid ≤ 200 mg/dL, Bilirubin (Conjugated) ≤ 59.9 mg/dL, Calcium ≤ 26.0 mg/dL, Glucose ≤ 1220 mg/dL, Hemoglobin ≤ 1200 mg/dL, Phosphorous ≤ 307 mg/dL, Boric Acid ≤ 1000 mg/dL, 6N Hydrochloric Acid ≤ 3.0 mL/dL, Copper ≤ 21.6 µg/dL, Zinc ≤ 3504 µg/L, Iron ≤ 0.6 mg/dL).
For magnesium samples targeted to 14 or 15 mg/dL: similar results for the same interferents with slightly different calcium and bilirubin levels.
Acetic acid, nitric acid, and sodium fluoride did not meet the ±10% criterion and are noted as limitations. |
| Linearity | The assay should be linear across its analytical measuring interval. (No explicit R-squared or slope criterion, but stated that it was "demonstrated to be linear"). | Urine application demonstrated linearity across 1.04 to 36.24 mg/dL, spanning the analytical measuring interval of 1.81 to 26.35 mg/dL. |
| Measuring Interval (Analytical Measuring Range) | Defined by LoQ and highest linear point. | 1.81 to 26.35 mg/dL |
| Method Comparison (Correlation to Predicate) | Demonstrate acceptable correlation (slope and correlation coefficient) to the predicate device across the measuring interval. | Urine application showed acceptable correlation to predicate:
- pH
§ 862.1495 Magnesium test system.
(a)
Identification. A magnesium test system is a device intended to measure magnesium levels in serum and plasma. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low plasma levels of magnesium) and hypermagnesemia (abnormally high plasma levels of magnesium).(b)
Classification. Class I.