ACE CARBON DIOXIDE(CO2-LC) REAGENT, ACE DIRECT BILIRUBIN REAGENT, ACE TOTAL BILIRUBIN REAGENT, ACE MAGNESIUM REAGENT
Device Facts
| Record ID | K113435 |
|---|---|
| Device Name | ACE CARBON DIOXIDE(CO2-LC) REAGENT, ACE DIRECT BILIRUBIN REAGENT, ACE TOTAL BILIRUBIN REAGENT, ACE MAGNESIUM REAGENT |
| Applicant | Alfa Wassermann |
| Product Code | KHS · Clinical Chemistry |
| Decision Date | Jul 2, 2012 |
| Decision | SESE |
| Submission Type | Traditional |
| Regulation | 21 CFR 862.1160 |
| Device Class | Class 2 |
| Attributes | Real-World Evidence |
Real-World Evidence
| Submission | Device | Sponsor | RWD Sources | RWE Use Summary | Key Tags |
|---|---|---|---|---|---|
| K113435 · Jul 2, 2012 | ACE CARBON DIOXIDE(CO2-LC) REAGENT, ACE DIRECT BILIRUBIN REAGENT, ACE TOTAL BILIRUBIN REAGENT, ACE MAGNESIUM REAGENT | Alfa Wassermann | Patient serum samples from clinical correlation studies | Patient serum samples were used to evaluate the accuracy and correlation of the ACE Axcel Clinical Chemistry System reagents (CO2, Direct Bilirubin, Total Bilirubin, and Magnesium) against the predicate ACE Clinical Chemistry System in clinical laboratory settings. | Correlation study; Clinical laboratory samples; Accuracy; Method comparison |
Clinical Evidence
| Study Design | Population | Comparator | Key Endpoints |
|---|---|---|---|
| Patient Correlation Studies; Retrospective method comparison study | Clinical patient serum samples; Sample Size: 108 to 120 samples per analyte; Number of Sites: 3 Physician Office Laboratory (POL) sites | Alfa Wassermann ACE Clinical Chemistry System (predicate) | Correlation coefficient, standard error estimate, slope, and intercept |
Indications for Use
The ACE Carbon Dioxide (CO₂-LC) Reagent is intended for the quantitative determination of carbon dioxide in serum using the ACE Axcel Clinical Chemistry System. Bicarbonate/carbon dioxide measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only. The ACE Direct Bilirubin Reagent is intended for the quantitative determination of direct bilirubin in serum using the ACE Axcel Clinical Chemistry Systems. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological and metabolic disorders, including hepatitis and gall bladder block. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only. The ACE Total Bilirubin Reagent is intended for the quantitative determination of total bilirubin in serum using the ACE Axcel Clinical Chemistry System. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological and metabolic disorders, including hepatitis and gall bladder block. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only. The ACE Magnesium Reagent is intended for the quantitative determination of magnesium in serum using the ACE Axcel Clinical Chemistry 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). This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
Device Story
Reagents for quantitative serum analysis on ACE Axcel Clinical Chemistry System; CO2 (enzymatic), Bilirubin (diazo colorimetry), Magnesium (photometric). Input: serum samples; processed via automated photometric measurement of absorbance changes. Output: concentration values for CO2, direct/total bilirubin, and magnesium. Used in clinical labs/POLs by technicians/clinicians. Results assist in diagnosing acid-base, liver, and metabolic disorders. Benefits: rapid, automated diagnostic testing for patient management.
Clinical Evidence
Bench testing only. Precision (within-run/total CVs), accuracy (correlation studies vs. predicate), and detection limits reported for all four reagents. Correlation studies (n=108-120 samples) showed high correlation (r=0.9690-0.9997) with predicate. Precision studies conducted over 22 days and at three POL sites over 5 days.
Technological Characteristics
Liquid, ready-to-use reagents. CO2: enzymatic (PEPC/MD). Bilirubin: diazo colorimetry. Magnesium: Xylidyl blue-1 photometric. Analyzed on ACE Axcel Clinical Chemistry System. Calibration traceable to NIST SRM 351, 916, 909. Software-controlled automated photometric analysis.
Indications for Use
Indicated for quantitative determination of CO2, direct bilirubin, total bilirubin, and magnesium in serum. Used in clinical/physician office labs for diagnosis/treatment of acid-base balance disorders, liver/hemolytic/hematological/metabolic disorders (hepatitis, gall bladder block), and magnesium level abnormalities (hypomagnesemia/hypermagnesemia).
Regulatory Classification
Identification
A bicarbonate/carbon dioxide test system is a device intended to measure bicarbonate/carbon dioxide in plasma, serum, and whole blood. Bicarbonate/carbon dioxide measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.
Predicate Devices
Submission Summary (Full Text)
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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE
A. 510(k) Number:
k113435
B. Purpose for Submission:
New device
C. Measurand:
Carbon Dioxide, Direct Bilirubin, Total Bilirubin, and Magnesium
D. Type of Test:
Quantitative
Enzymatic activity (CO₂), Diazo Colorimetry (Direct and Total Bilirubin), and Photometric (Magnesium)
E. Applicant:
Alfa Wassermann
F. Proprietary and Established Names:
ACE Carbon Dioxide (CO₂-LC) Reagent
ACE Direct Bilirubin Reagent
ACE Total Bilirubin Reagent
ACE Magnesium Reagent
G. Regulatory Information:
| Product Code | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| KHS | II | 862.1160, Bicarbonate/Carbon-Dioxide test system | 75-Chemistry |
| CIG | II | 862.1110, Bilirubin (total or direct) test system | 75-Chemistry |
| JGJ | II | 862.1495, Magnesium test system | 75-Chemistry |
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H. Intended Use:
1. Intended use(s):
See indications for use below.
2. Indication(s) for use:
The ACE Carbon Dioxide (CO₂-LC) Reagent is intended for the quantitative determination of carbon dioxide in serum using the ACE Axcel Clinical Chemistry System. Bicarbonate/carbon dioxide measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
The ACE Direct Bilirubin Reagent is intended for the quantitative determination of direct bilirubin in serum using the ACE Axcel Clinical Chemistry Systems. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological and metabolic disorders, including hepatitis and gall bladder block. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
The ACE Total Bilirubin Reagent is intended for the quantitative determination of total bilirubin in serum using the ACE Axcel Clinical Chemistry System. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic, hematological and metabolic disorders, including hepatitis and gall bladder block. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
The ACE Magnesium Reagent is intended for the quantitative determination of magnesium in serum using the ACE Axcel Clinical Chemistry 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). This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
3. Special conditions for use statement(s):
For in vitro diagnostic use only. For prescription and point-of-care use.
4. Special instrument requirements:
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ACE Axcel Clinical Chemistry System
I. Device Description:
The ACE Carbon Dioxide Reagent comes in a kit containing 4 x 7.5 mL Carbon Dioxide Reagent and 1 x 15 mL 30 mEq/L Carbon Dioxide Standard. The kit supports 500 tests.
The ingredients of the reagents are:
Carbon Dioxide Reagent
Phosphoenolpyruvate (PEP) 63 mmol/L
Nicotinamide adenine dinucleotide (NADH) analog, reduced 3.0 mmol/L
Phosphoenol pyruvate carboxylase (PEPC) (Microbial) >2000 U/L
Malate dehydrogenase (MD) (Mammalian) >20 KU/L
Buffer (pH 7.5 @ 25°C)
Activators, Stabilizers, Surfactant and Preservative
Carbon Dioxide Standard
Sodium carbonate 30 mEq/L, Buffer and Preservative
The ACE Direct Bilirubin Reagent comes in a kit containing 3x12 mL Direct Bilirubin Reagent and 3x3mL Sodium Nitrite Reagent. Each kit supports 120 tests.
The ingredients of the reagents are:
Direct Bilirubin Reagent
Sulfanilic acid 35.6 mmol/L
Hydrochloric acid 165 mmol/L
Sodium Nitrite Reagent
Sodium nitrite 43.5 mmol/L
The ACE Total Bilirubin Reagent comes in a kit containing 3x30 mL Total Bilirubin Reagent and 3x6mL Sodium Nitrite Reagent. Each kit supports 300 tests.
The ingredients of the reagents are:
Total Bilirubin Reagent
Sulfanilic acid 35.6 mmol/L
Hydrochloric acid 165 mmol/L
Dimethyl sulfoxide (DMSO) 50% (v/v)
Sodium Nitrite Reagent
Sodium nitrite 60.0 mmol/L
The ACE Magnesium Reagent comes in a kit containing 6x12 mL liquid ready-to-use bottles. Each kit supports 160 tests.
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ACE Magnesium Reagent has the following composition:
Xylidyl blue-1 0.14 mmol/L
EGTA 0.1 mmol/L
Buffer and Surfactant
## J. Substantial Equivalence Information:
1. Predicate device name(s):
ACE Clinical Chemistry System, ACE Carbon Dioxide (CO₂-LC) Reagent
ACE Clinical Chemistry System, ACE Direct Bilirubin Reagent
ACE Clinical Chemistry System, ACE Total Bilirubin Reagent
ACE Clinical Chemistry System, ACE Magnesium Reagent
2. Predicate 510(k) number(s):
k931786
3. Comparison to predicate
| Items | ACE Axcel Clinical Chemistry System, ACE Carbon Dioxide (CO₂-LC) Reagent (Candidate Device) | ACE Clinical Chemistry System, ACE Carbon Dioxide (CO₂-LC) Reagent (Predicate Device) |
| --- | --- | --- |
| Similarity | | |
| Intended use /Indication for use | Same | For the quantitative determination of carbon dioxide in serum. Bicarbonate/carbon dioxide measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance. For in vitro diagnostic use only. |
| Test Principle | Same | Phosphoenolpyruvate (PEP) and HCO₃⁻ react to form oxaloacetate and phosphate in the presence of phosphoenolpyruvate carboxylase. Malate dehydrogenase catalyzes the reaction of oxaloacetate and reduced nicotinamide adenine dinucleotide (NADH) to NAD⁺ and malate. The change in absorbance due to the conversion |
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| | | of NADH to NAD+ is directly proportional to the amount of CO2 in the sample. |
| --- | --- | --- |
| Reaction Type | Same | Kinetic |
| Reactive Ingredients | Same | Phosphoenolpyruvate NADH Phosphoenol pyruvate decarboxylase Malate dehydrogenase Buffer (pH 7.5 at 25°C) |
| Non-reactive Ingredients | Same | Activators, stabilizers, surfactant and preservative |
| Sample Type | Same | Serum |
| Sample Volume | Same | 6 μL |
| Reaction Volume (total) | Same | 156 μL |
| Calibration | Same | 30 mEq/L Carbon Dioxide Standard |
| Difference | | |
| Instrument Platforms | ACE Axcel Clinical Chemistry System | ACE and ACE Alera® Clinical Chemistry Systems |
| Detection Limit | 1.2 mEq/L | 2 mEq/L |
| Reportable Range | 4 to 50 mEq/L | 2 to 50 mEq/L |
| Items | ACE Axcel Clinical Chemistry System, ACE Direct Bilirubin Reagent (Candidate Device) | ACE Clinical Chemistry System, ACE Direct Bilirubin Reagent (Predicate Device) |
| --- | --- | --- |
| Similarity | | |
| Intended use /Indication for use | Same | For the quantitative determination of direct bilirubin in serum. For in vitro diagnostic use only. |
| Test Principle | Same | Reaction of direct bilirubin with diazotized sulfanilic acid to form azobilirubin; resulting increase in absorbance measured, one minute after sample addition, bichromatically at 554/692 nm. |
| Reaction | Same | Endpoint |
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| Type | | |
| --- | --- | --- |
| Reactive Ingredients | Same | Sulfanilic acid Hydrochloric acid Sodium nitrite |
| Non-reactive Ingredients | Same | None |
| Sample Type | Same | Serum |
| Sample Volume | Same | 20 μL |
| Reaction Volume (total) | Same | 355 μL |
| Reportable Range | Same | 2 to 50 mEq/L |
| Calibration | Same | Calibrated by referencing the change in absorbance of the unknown samples to the change in absorbance of the calibrator. The use of GEMCAL Reference Serum is recommended. |
| Difference | | |
| Instrument Platforms | ACE Axcel Clinical Chemistry System | ACE and ACE Alera® Clinical Chemistry Systems |
| Detection Limit | 0.1 mg/dL | 0 mg/dL |
| Reportable Range | 0.1 to 14.0 mg/dL | Up to 14.0 mg/dL |
| Items | ACE Axcel Clinical Chemistry System, ACE Total Bilirubin Reagent (Candidate Device) | ACE Clinical Chemistry System, ACE Total Bilirubin Reagent (Predicate Device) |
| --- | --- | --- |
| Similarity | | |
| Intended use /Indication for use | Same | For the quantitative determination of total bilirubin in serum. For in vitro diagnostic use only. |
| Test Principle | Same | Reaction of total bilirubin with diazotized sulfanilic acid to form azobilirubin; resulting increase in absorbance measured, one minute after sample addition, bichromatically at 554/692 nm. |
| Reaction Type | Same | Endpoint |
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| Reactive Ingredients | Same | Sulfanilic acid Hydrochloric acid Dimethyl sulfoxide (DMSO) Sodium nitrite |
| --- | --- | --- |
| Non-reactive Ingredients | Same | None |
| Sample Type | Same | Serum |
| Sample Volume | Same | 20 μL |
| Reaction Volume (total) | Same | 380 μL |
| | | |
| Calibration | Same | Calibrated by referencing the change in absorbance of the unknown samples to the change in absorbance of the calibrator. The use of GEMCAL Reference Serum is recommended. |
| Difference | | |
| Instrument Platforms | ACE Axcel Clinical Chemistry System | ACE and ACE Alera® Clinical Chemistry Systems |
| Detection Limit | 0.1 mg/dL | 0 mg/dL |
| Reportable Range | 0.2 to 40.0 mg/dL | Up to 40.0 mg/dL |
| Items | ACE Axcel Clinical Chemistry System, ACE Magnesium Reagent (Candidate Device) | ACE Clinical Chemistry System, ACE Magnesium Reagent (Predicate Device) |
| --- | --- | --- |
| Similarity | | |
| Intended use /Indication for use | Same | For the quantitative determination of Magnesium in serum. For in vitro diagnostic use only. |
| Test Principle | Same | Magnesium ions in serum react with Xylidyl blue-1 in an alkaline medium to produce a red complex which is measured bichromatically at 525 nm/692 nm. The intensity of the color produced is directly proportional to the magnesium concentration. EGTA prevents calcium interference by preferential chelation of calcium |
| | | in the presence of calcium. The amount of calcium in the sample is 1000 mg/kg. The amount of calcium in the sample is 1000 mg/kg. The amount of calcium in the sample is 1000 mg/kg. The amount of calcium in the sample is 1000 mg/kg. The amount of calcium in the sample is 1000 mg/kg |
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| | | present in the sample. A surfactant system is included to remove protein interference. |
| --- | --- | --- |
| Reaction Type | Same | Endpoint |
| Reactive Ingredients | Same | Xylidyl blue-1 EGTA |
| Non-reactive Ingredients | Same | Buffer Surfactant |
| Sample Type | Same | Serum |
| Sample Volume | Same | 3 μL |
| Reaction Volume (total) | Same | 488 μL |
| | | |
| Calibration | Same | Calibrated by referencing the change in absorbance of the unknown samples to the change in absorbance of the calibrator. The use of GEMCAL Reference Serum is recommended. |
| Difference | | |
| Instrument Platforms | ACE Axcel Clinical Chemistry System | ACE and ACE Alera® Clinical Chemistry Systems |
| Detection Limit | 0.1 mg/dL | 0 mg/dL |
| Reportable Range | 0.4 to 6.0 mg/dL | Up to 6.0 mg/dL |
# K. Standard/Guidance Document Referenced (if applicable):
CLSI EP5-A2: Evaluation of Precision Performance of Quantitative Measurement Methods; Approved Guideline-Second Edition
CLSI EP6-A: Evaluation of Linearity of Quantitative Measurement Procedures, A Statistical Approach; Approved Guideline
CLSI EP7-A2: Interference Testing in Clinical Chemistry; Approved Guideline-Second Edition
CLSI EP9-A2-IR: Method Comparison and Bias Estimation Using Patient Samples; Approved Guideline-Second Edition
CLSI EP10-A3: Preliminary Evaluation of Quantitative Clinical Laboratory Measurement Procedures; Approved Guideline-Third Edition
CLSI EP17-A: Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline
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L. Test Principle:
In the ACE CO2 Assay, carbon dioxide (in the form of bicarbonate HCO3-) reacts with phosphoenolpyruvate (PEP) in the presence of phosphoenolpyruvate carboxylase (PEPC) and magnesium to yield oxaloacetic acid (OAA) and phosphate. In the presence of malate dehydrogenase (MD), the reduced cofactor is oxidized by oxaloacetic acid. The reduced cofactor absorbs strongly at 408 nm whereas its oxidized form does not. The rate of decrease in absorbance, monitored bichromatically at 408 nm/692 nm, is proportional to the carbon dioxide content of the sample.
In the ACE Direct Bilirubin Assay, sodium nitrite added to sulfanilic acid forms diazotized sulfanilic acid. Bilirubin glucuronide in serum reacts with diazotized sulfanilic acid to form azobilirubin, which absorbs strongly at 554 nm. The increase in absorbance, measured bichromatically at 554 nm/692 nm, one minute after sample addition, is directly proportional to the direct bilirubin concentration.
In the ACE Total Bilirubin Assay, sodium nitrite, when added to sulfanilic acid, forms diazotized sulfanilic acid. Bilirubin in serum reacts with diazotized sulfanilic acid to form azobilirubin, which absorbs strongly at 554 nm. The inclusion of DMSO in the reagent as an accelerator, causes both direct and indirect bilirubin to react rapidly. The increase in absorbance, measured bichromatically at 554 nm/692 nm, is directly proportional to the total bilirubin concentration.
In the ACE Magnesium Assay, magnesium ions in serum react with Xylidyl blue-1 in an alkaline medium to produce a red complex which is measured bichromatically at 525 nm/692 nm. The intensity of color produced is directly proportional to the magnesium concentration. EGTA prevents calcium interference by preferential chelation of calcium present in the sample. A surfactant system is included to remove protein interference.
M. Performance Characteristics (if/when applicable):
1. Analytical performance:
a. Precision/Reproducibility:
In-house precision
Precision studies were conducted by testing human serum pools at four levels. The samples were run 2 times per run, 2 runs per day, for a total of 22 days using one instrument. Results are summarized below.
CO2:
| Sample | Mean (mEq/L) | Within Run | | Between Run | | Between Day | | Total | |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1 | 14.25 | SD | 0.27 | SD | 0.34 | SD | 0.35 | SD | 0.55 |
| | | CV | 1.9% | CV | 2.4% | CV | 2.4% | CV | 3.9% |
| 2 | 21.68 | SD | 1.49 | SD | 0.56 | SD | 0.00 | SD | 1.59 |
| | | CV | 6.9% | CV | 2.6% | CV | 0.0% | CV | 7.4% |
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| 3 | 32.62 | SD 1.88 | SD 0.63 | SD 0.00 | SD 1.98 |
| --- | --- | --- | --- | --- | --- |
| | | CV 5.8% | CV 1.9% | CV 0.0% | CV 6.1% |
| 4 | 22.53 | SD 0.35 | SD 0.63 | SD 0.64 | SD 0.97 |
| | | CV 1.6% | CV 2.8% | CV 2.8% | CV 4.3% |
Direct Bilirubin:
| Sample | Mean (mg/dL) | Within Run | Between Run | Between Day | Total |
| --- | --- | --- | --- | --- | --- |
| 1 | 0.30 | SD 0.02 | SD 0.00 | SD 0.00 | SD 0.02 |
| | | CV 7.2% | CV 0.0% | CV 0.0% | CV 7.2% |
| 2 | 5.16 | SD 0.07 | SD 0.04 | SD 0.06 | SD 0.10 |
| | | CV 1.4% | CV 0.7% | CV 1.1% | CV 1.9% |
| 3 | 9.03 | SD 0.08 | SD 0.00 | SD 0.12 | SD 0.14 |
| | | CV 0.8% | CV 0.0% | CV 1.3% | CV 1.5% |
| 4 | 0.21 | SD 0.04 | SD 0.00 | SD 0.00 | SD 0.04 |
| | | CV 16.5% | CV 0.0% | CV 2.3% | CV 16.6% |
Total Bilirubin:
| Sample | Mean (mg/dL) | Within Run | Between Run | Between Day | Total |
| --- | --- | --- | --- | --- | --- |
| 1 | 0.58 | SD 0.04 | SD 0.02 | SD 0.00 | SD 0.05 |
| | | CV 7.3% | CV 4.1% | CV 0.0% | CV 8.4% |
| 2 | 13.05 | SD 0.14 | SD 0.00 | SD 0.14 | SD 0.19 |
| | | CV 1.0% | CV 0.0% | CV 1.1% | CV 1.5% |
| 3 | 24.67 | SD 0.14 | SD 0.03 | SD 0.24 | SD 0.28 |
| | | CV 0.6% | CV 0.1% | CV 1.0% | CV 1.1% |
| 4 | 0.53 | SD 0.06 | SD 0.00 | SD 0.00 | SD 0.06 |
| | | CV 10.6% | CV 0.0% | CV 0.0% | CV 10.6% |
Magnesium:
| Sample | Mean (mg/dL) | Within Run | Between Run | Between Day | Total |
| --- | --- | --- | --- | --- | --- |
| 1 | 2.19 | SD 0.12 | SD 0.07 | SD 0.03 | SD 0.14 |
| | | CV 5.6% | CV 3.1% | CV 1.6% | CV 6.6% |
| 2 | 3.89 | SD 0.12 | SD 0.03 | SD 0.11 | SD 0.17 |
| | | CV 3.1% | CV 0.9% | CV 2.8% | CV 4.2% |
| 3* | 4.83 | SD 0.13 | SD 0.08 | SD 0.12 | SD 0.20 |
| | | CV 2.7% | CV 1.6% | CV 2.6% | CV 4.1% |
| 4 | 1.71 | SD 0.10 | SD 0.08 | SD 0.00 | SD 0.13 |
| | | CV 5.9% | CV 4.7% | CV 0.0% | CV 7.6% |
*Data collected for 21 days
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Point-of-Care precision
Precision studies were also conducted at 3 Physician Office Laboratories (POL). Human serum pools and QC samples were tested in triplicate over at least 5 different days. The results are presented below:
CO2:
| Lab | Sample | Mean (mEq/L) | %CV or SD (mg/dL) | |
| --- | --- | --- | --- | --- |
| | | | Within-Run | Total |
| POL 1 | 1 | 16.89 | SD 0.29 | SD 0.69 |
| | | | CV 1.7% | CV 4.1% |
| POL 2 | 1 | 16.16 | SD 0.35 | SD 0.85 |
| | | | CV 2.2% | CV 5.3% |
| POL 3 | 1 | 18.41 | SD 0.48 | SD 1.04 |
| | | | CV 2.6% | CV 5.7% |
| POL 1 | 2 | 27.58 | SD 0.54 | SD 0.79 |
| --- | --- | --- | --- | --- |
| | | | CV 2.0% | CV 2.9% |
| POL 2 | 2 | 27.40 | SD 0.68 | SD 1.33 |
| | | | CV 2.5% | CV 4.9% |
| POL 3 | 2 | 29.58 | SD 0.31 | SD 0.53 |
| | | | CV 1.0% | CV 1.8% |
| POL 1 | 3 | 38.64 | SD 0.50 | SD 0.91 |
| --- | --- | --- | --- | --- |
| | | | CV 1.3% | CV 2.3% |
| POL 2 | 3 | 37.34 | SD 0.58 | SD 1.34 |
| | | | CV 1.6% | CV 3.6% |
| POL 3 | 3 | 39.66 | SD 0.45 | SD 0.88 |
| | | | CV 1.1% | CV 2.2% |
Direct Bilirubin:
| Lab | Direct Bilirubin | Mean (mg/dL) | %CV or SD (mg/dL) | |
| --- | --- | --- | --- | --- |
| | | | Within-Run | Total |
| POL 1 | Control 1 | 0.9 | SD 0.00 | SD 0.00 |
| | | | %CV 0.0% | %CV 0.0% |
| POL 2 | Control 1 | 0.9 | SD 0.03 | SD 0.03 |
| | | | %CV 3.3% | %CV 3.3% |
| POL 3 | Control 1 | 0.9 | SD 0.04 | SD 0.04 |
| | | | %CV 4.4% | %CV 4.4% |
| | | | | |
| POL 1 | Control 2 | 2.2 | SD 0.04 | SD 0.04 |
| | | | %CV 1.8% | %CV 1.8% |
| POL 2 | Control 2 | 2.3 | SD 0.07 | SD 0.07 |
| | | | %CV 3.0% | %CV 3.0% |
| POL 3 | Control 2 | 2.3 | SD 0.08 | SD 0.08 |
| | | | %CV 3.5% | %CV 3.5% |
| | | | | |
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| POL 1 | Sample 1 | 5.16 | SD 0.06 | SD 0.09 |
| --- | --- | --- | --- | --- |
| | | | %CV 1.2% | %CV 1.7% |
| POL 2 | Sample 1 | 5.16 | SD 0.11 | SD 0.15 |
| | | | %CV 2.1% | %CV 2.9% |
| POL 3 | Sample 1 | 5.19 | SD 0.10 | SD 0.10 |
| | | | %CV 2.0% | %CV 2.0% |
| | | | | |
| POL 1 | Sample 2 | 8.96 | SD 0.13 | SD 0.18 |
| | | | %CV 1.5% | %CV 2.0% |
| POL 2 | Sample 2 | 8.97 | SD 0.09 | SD 0.17 |
| | | | %CV 1.0% | %CV 1.9% |
| POL 3 | Sample 2 | 8.99 | SD 0.08 | SD 0.09 |
| | | | %CV 0.9% | %CV 1.0% |
Total Bilirubin:
| Lab | Sample | Mean (mg/dL) | %CV or SD (mg/dL) | |
| --- | --- | --- | --- | --- |
| | | | Within-Run | Total |
| POL 1 | Control 1 | 1.5 | SD 0.04 | SD 0.04 |
| | | | %CV 2.7% | %CV 2.7% |
| POL 2 | Control 1 | 1.5 | SD 0.05 | SD 0.05 |
| | | | %CV 3.3% | %CV 3.3% |
| POL 3 | Control 1 | 1.5 | SD 0.05 | SD 0.05 |
| | | | %CV 3.3% | %CV 3.3% |
| | | | | |
| POL 1 | Control 2 | 5.4 | SD 0.00 | SD 0.00 |
| | | | %CV 0.0% | %CV 0.0% |
| POL 2 | Control 2 | 5.4 | SD 0.14 | SD 0.14 |
| | | | %CV 2.6% | %CV 2.6% |
| POL 3 | Control 2 | 5.3 | SD 0.08 | SD 0.08 |
| | | | %CV 1.5% | %CV 1.5% |
| | | | | |
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Magnesium:
| Lab | Sample | Mean (mg/dL) | %CV or SD (mg/dL) | |
| --- | --- | --- | --- | --- |
| | | | Within-Run | Total |
| POL 1 | 1 | 2.22 | SD 0.07 | SD 0.07 |
| | | | CV 3.1% | CV 3.1% |
| POL 2 | 1 | 2.22 | SD 0.09 | SD 0.10 |
| | | | CV 4.1% | CV 4.6% |
| POL 3 | 1 | 2.06 | SD 0.07 | SD 0.14 |
| | | | CV 3.4% | CV 6.9% |
| | | | | |
| POL 1 | 2 | 4.02 | SD 0.11 | SD 0.12 |
| | | | CV 2.7% | CV 2.9% |
| POL 2 | 2 | 4.07 | SD 0.08 | SD 0.11 |
| | | | CV 2.0% | CV 2.6% |
| POL 3 | 2 | 3.80 | SD 0.11 | SD 0.15 |
| | | | CV 2.9% | CV 3.9% |
| | | | | |
| POL 1 | 3 | 5.69 | SD 0.07 | SD 0.11 |
| | | | CV 1.2% | CV 2.0% |
| POL 2 | 3 | 5.73 | SD 0.13 | SD 0.13 |
| | | | CV 2.4% | CV 2.4% |
| POL 3 | 3 | 5.38 | SD 0.14 | SD 0.20 |
| | | | CV 2.6% | CV 3.8% |
# b. Linearity/assay reportable range:
Linearity across the assay range was confirmed by spiking serum samples to a high concentration of analyte, then diluting the sample to obtain 10 levels to cover the measuring range of each assay. The assigned value of the highest sample was set to its mean value. The assigned values of the other levels were calculated by multiplying the mean value by the dilution ratios. Each level was tested in replicates of 3. Results are presented below:
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CO2
Linear Regression: $y = 0.998x + 1.3$ , $r^2 = 0.9958$
Based on the results of the linearity study and Limit of detection study (see below in $d$ ), the sponsor claimed that the assay's reportable range is 4-50 mEq/dL.
Direct Bilirubin
Linear Regression: $y = 0.990x - 0.113$ , $r^2 = 0.999$
Based on the results of the linearity study and Limit of detection study (see below in $d$ ), the sponsor claimed that the assay's reportable range is 0.1 to $14.0 \, \mathrm{mg/dL}$
Total Bilirubin
Linear Regression: $y = 1.003x + 0.18$ , $r^2 = 0.9998$
Based on the results of the linearity study and Limit of detection study (see below in $d$ ), the sponsor claimed that the assay's reportable range is 0.2 to $40.0 \, \mathrm{mg/dL}$
Magnesium
Linear Regression: $y = 0.987x + 0.07$ , $r^2 = 0.9983$
Based on the results of the linearity study and Limit of detection study (see below in $d$ ), the sponsor claimed that the assay's reportable range is 0.4 to $6.0 \, \mathrm{mg/dL}$
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
Traceability: CO2 method is traceable to NIST SRM 351. Total Bilirubin assay is traceable to NIST SRM 916. Direct Bilirubin assay is traceable to gravimetric standards prepared with NIST material. Magnesium method is traceable to NIST SRM 909.
The CO2 assay is calibrated by comparing the change in absorbance of the unknown sample to the change in absorbance of the $30\mathrm{mEq/L}$ CO2 standard included in the reagent kit. The CO2 standard was previously cleared under k854544. The Direct Bilirubin, Total Bilirubin and Magnesium assay is calibrated using the Gemcal Reference Serum previously cleared under k844344.
d. Detection limit:
The Limit of blank (LoB), limit of detection (LoD), and limit of quantification (LoQ) were determined according to CLSI EP17-A with the ACE Axcel Clinical Chemistry System. For the LoD studies, low samples and true blanks (n=60 reps, 20 reps per day) were tested over three days on two ACE Axcel Clinical Chemistry Systems. For the LoQ studies, samples (n = 40 reps, 8 reps per run) were tested in five separate runs over five days. The results are as follows:
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| Analyte | LoB | LoD | LoQ |
| --- | --- | --- | --- |
| CO2 (mEq/L) | 1.0 | 1.2 | 2.9 |
| Direct Bilirubin (mg/dL) | 0.1 | 0.1 | 0.1 |
| Total Bilirubin (mg/dL) | 0.2 | 0.2 | 0.2 |
| Mg (mg/dL) | 0.2 | 0.2 | 0.4 |
# e. Analytical specificity:
Interference studies were performed to determine the effects from potential interferents. The various concentration of interferent was spiked into serum pools containing analytes at normal and abnormal concentrations. All samples were tested in triplicate. Six interferent levels and the control were tested for each interferent. Interference is defined as a result that is different from the control by more than the least detectable dose of the assay $(+/-0.1\mathrm{mg / dL}$ for direct and total bilirubin assay) or $+/-10\%$ for CO2 and Magnesium. The tested ranges and analyte concentrations are presented in the product labeling.
CO2:
| Interferent Compound | Concentration with No Interference Up To |
| --- | --- |
| Ascorbic Acid | 6 mg/dL |
| Unconjugated Bilirubin | 55 mg/dL |
| Hemoglobin | 500 mg/dL |
| Intralipid | 1000 mg/dL |
Direct Bilirubin:
| Interferent Compound | Concentration with No Interference Up To |
| --- | --- |
| Ascorbic Acid | 6 mg/dL |
| Hemoglobin | 31.3 mg/dL* |
| Intralipid | 542 mg/dL |
* Specimens showing indication of hemolysis should not be analyzed.
Total Bilirubin:
| Interferent Compound | Concentration with No Interference Up To |
| --- | --- |
| Ascorbic Acid | 6 mg/dL |
| Hemoglobin | 62.5 mg/dL* |
| Intralipid | 650 mg/dL |
*Specimens showing any indication of hemolysis should not be analyzed.
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Magnesium:
| Interferent Compound | Concentration with No Interference Up To |
| --- | --- |
| Ascorbic Acid | 6 mg/dL |
| Unconjugated Bilirubin | 30 mg/dL |
| Hemoglobin | 125 mg/dL* |
| Intralipid | 315 mg/dL |
*Specimens showing any indication of hemolysis should not be analyzed.
f. Assay cut-off:
Not applicable.
2. Comparison studies:
a. Method comparison with predicate device:
An in-house method comparison study to the predicate device was performed with serum patient samples. A small number of the samples $(< 10\%)$ were spiked or diluted to cover the low and high end of the assay range for each analyte. The results are presented in the table below:
| Analyte | n | Regression Equation | r2 | Sample range |
| --- | --- | --- | --- | --- |
| CO2 | 119 | y=0.984x-0.18 | 0.9735 | 6.4-47.6 mEq/L |
| Direct Bilirubin | 116 | y=0.972x+0.00 | 0.9997 | 0.2-12.5 mg/dL |
| Total Bilirubin | 117 | y=0.966x+0.01 | 0.9997 | 0.2-34.8 mg/dL |
| Magnesium | 108 | y=0.998x+0.03 | 0.9690 | 0.6-5.5 mg/dL |
Additional method comparison studies were performed at three Physician Office Laboratories using patient serum specimens. The results are presented in the tables below:
$\mathrm{CO}_{2}$
| POL | n | Regression Equation | r2 | Sample range (mEq/L) |
| --- | --- | --- | --- | --- |
| 1 | 56 | y = 1.003x + 0.29 | 0.9819 | 6.5-43.6 |
| 2 | 52 | y = 1.014x - 0.01 | 0.9917 | 8.2-49.0 |
| 3 | 46 | y = 1.050x - 1.06 | 0.9952 | 5.6-49.4 |
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Direct Bilirubin
| POL | n | Regression Equation | r² | Sample range (mg/dL) |
| --- | --- | --- | --- | --- |
| 1 | 56 | y = 1.006x + 0.01 | 0.9997 | 0.1-12.7 |
| 2 | 60 | y = 1.017x + 0.00 | 0.9996 | 0.1-13.8 |
| 3 | 48 | y = 0.992x + 0.01 | 0.9996 | 0.1-13.0 |
Total Bilirubin
| POL | n | Regression Equation | r² | Sample range (mg/dL) |
| --- | --- | --- | --- | --- |
| 1 | 58 | y = 1.015x - 0.01 | 1.0000 | 0.2-38.7 |
| 2 | 62 | y = 1.019x + 0.02 | 0.9999 | 0.2-35.0 |
| 3 | 50 | y = 1.045x - 0.04 | 0.9993 | 0.2-36.9 |
Magnesium
| POL | n | Regression Equation | r² | Sample range (mg/dL) |
| --- | --- | --- | --- | --- |
| 1 | 49 | y = 0.957x + 0.06 | 0.9917 | 0.7-5.7 |
| 2 | 47 | y = 0.986x + 0.13 | 0.9930 | 0.9-5.9 |
| 3 | 47 | y = 1.037x - 0.25 | 0.9858 | 0.6-5.6 |
b. Matrix comparison:
The device is being cleared for serum use only.
3. Clinical studies:
a. Clinical Sensitivity:
Not applicable
b. Clinical specificity:
Not applicable
c. Other clinical supportive data (when a. and b. are not applicable):
Not applicable
4. Clinical cut-off:
Not applicable. Clinical studies are not typically submitted for this device type.
5. Expected values/Reference range:
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The following expected values are provided in the product insert based on the literature for each analyte. The sponsor stated that each laboratory should determine the expected values for its particular population.
CO₂: 23-29 mEq/L
Direct Bilirubin: <0.2 mg/dL
Total Bilirubin: 0.2-1.0 mg/dL
Mg: 1.3-2.2 mEq/L, 1.6-2.6 mg/dL
Tietz, N.W. (Ed.), Clinical Guide to Laboratory Tests, 4th Edition, W.B. Saunders Co., Philadelphia, PA (2006).
N. Proposed Labeling:
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.
O. Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
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