The SPOTCHEM II Creatinine test is intended to measure the concentration of creatinine in serum, plasma, and whole blood. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for measuring other urine analytes. The SPOTCHEM II Amylase test is intended to measure amylase activity in serum, plasma, and whole blood. Amylase measurements are used primarily for the diagnosis and treatment of pancreatitis (inflammation of the pancreas). The SPOTCHEM II ALP test is intended to measure ALP activity in serum, plasma, and whole blood. Measurements of alkaline phosphatase or its isoenzymes are used in the diagnosis and treatment of liver, bone, parathyroid, and intestinal diseases.
Device Story
SpotChem II assays (Creatinine, Amylase, ALP) are in vitro diagnostic reagents for use on SpotChem EZ Analyzer. Device consists of plastic strip with multi-layered test field (sample-retention, reagent, support layers). User applies serum, plasma, or whole blood to test field; sample permeates reagent layer to initiate colorimetric reaction. Analyzer uses reflectance spectrophotometry (550 nm for Creatinine; 405 nm for Amylase/ALP) to measure color intensity/rate. Output is quantitative analyte concentration/activity. Used in clinical settings by healthcare professionals. Results assist clinicians in diagnosing/monitoring renal, pancreatic, liver, bone, parathyroid, and intestinal conditions.
Clinical Evidence
No clinical data provided; substantial equivalence based on bench testing and performance characteristics typical for in vitro diagnostic test systems.
Technological Characteristics
Plastic reagent strip with multi-layered test field (sample-retention, reagent, support). Principle: reflectance spectrophotometry. Energy source: SpotChem EZ Analyzer. Connectivity: magnetic card for lot-specific calibration data. Sterilization: not specified. Software: embedded analyzer firmware for calculation and data processing.
Indications for Use
Indicated for patients requiring measurement of creatinine, amylase, or alkaline phosphatase (ALP) in serum, plasma, or whole blood for the diagnosis and treatment of renal, pancreatic, liver, bone, parathyroid, or intestinal diseases.
Regulatory Classification
Identification
A creatinine test system is a device intended to measure creatinine levels in plasma and urine. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for measuring other urine analytes.
Submission Summary (Full Text)
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# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE
A. 510(k) Number:
k050652
B. Purpose for Submission:
Notification of intent to market 3 assays: SpotChem II Creatinine, Amylase and Alkaline Phosphatase (ALP).
C. Measurand:
Creatinine, Amylase and Alkaline Phosphatase (ALP)
D. Type of Test:
Quantitative, Colorimetric
E. Applicant:
Arkray, Inc.
F. Proprietary and Established Names:
Spotchem II Creatinine
Spotchem II Amylase
Spotchem II Alkaline Phosphatase (ALP)
G. Regulatory Information:
1. Regulation section:
Creatinine - 21CFR §862.1225; Creatinine test system
Amylase - 21CFR §862.1070; Amylase test system
ALP - 21CFR §862.1050; Alkaline phosphatase or isoenzymes test system
2. Classification:
Class II
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3. Product code:
Creatinine – CGX, Alkaline Picrate, Colorimetry, Creatinine Amylase – CIJ, Saccharogenic, Amylase ALP – CJE, Nitrophenylphosphate, Alkaline Phosphatase or isoenzymes
4. Panel:
75 (Chemistry)
H. Intended Use:
1. Intended use(s):
See indications for use below.
2. Indication(s) for use:
The SPOTCHEM II Creatinine test is intended to measure the concentration of creatinine in serum, plasma and whole blood. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis and as a calculation basis for measuring other urine analytes.
The SPOTCHEM II Amylase test is intended to measure amylase activity in serum, plasma and whole blood. Amylase measurements are used primarily for the diagnosis and treatment of pancreatitis (inflammation of the pancreas).
The SPOTCHEM II ALP test is intended to measure ALP activity in serum, plasma and whole blood. Measurements of alkaline phosphatase or its isoenzymes are used in the diagnosis and treatment of liver, bone, parathyroid and intestinal diseases.
3. Special conditions for use statement(s):
For Prescription use only
4. Special instrument requirements:
These assays are intended for use on the SpotChem EZ Analyzer (k040332).
I. Device Description:
The SpotChem II Creatinine, Amylase and ALP assays are in vitro diagnostic procedures intended to measure creatinine, amylase and ALP quantitatively in human serum and plasma on the SpotChem EZ Analyzer.
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The device is composed of a plastic strip to which a multi-layered test field is affixed. The layers consist of a sample-retention layer, a layer containing the reagent and a support layer.
A fixed amount of serum or plasma is placed on the test field of the reagent strip. The serum or plasma spreads in a uniform fashion across the entire surface of the sample retention layer. The serum or plasma then permeates into the reagent layer where the reaction is initiated.
## J. Substantial Equivalence Information:
1. Predicate device name(s):
Vitros Creatinine Slides, 821 2763
PolyChem Amylase kit, AMY500
PolyChem ALP kit, ALP500
2. Predicate 510(k) number(s):
k001769
k020852
k020852
3. Comparison with predicate:
| | Creatinine | Amylase | ALP |
| --- | --- | --- | --- |
| Predicate Methodology | Colorimetric, enzyme-based | Colorimetric enzyme-based | Colorimetric |
| Test Methodology | Colorimetric | Colorimetric, enzyme-based | Colorimetric |
| Predicate Reagent Storage | 2-8 °C | 2-8 °C | 2-8 °C |
| Test Reagent Storage | 2-8 °C | 2-8 °C | 2-8 °C |
| Predicate Sample types | Serum/Plasma, Urine | Serum/Plasma, Urine | Serum/Plasma, |
| Test Sample Types | Serum/Plasma, Whole blood | Serum/Plasma, Whole blood | Serum/Plasma, Whole blood |
| Predicate Controls | Recommended | Recommended | Recommended |
| Test Controls | Recommended | Recommended | Recommended |
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| Correlation with Predicate device | N = 50. Samples spanned from 0.7 – 11.8 mg/dL. The regression equation was y = 0.926x + 0.184 and r = 0.997. | N = 40. Samples spanned from 17 – 738 IU/L. The regression equation was y = 1.059x – 6.206 and r = 0.998 | N = 40. Samples spanned from 43 - 814 IU/L. The regression equation was y = 0.971x – 0.218 and r = 0.990. |
| --- | --- | --- | --- |
## K. Standard/Guidance Document Referenced (if applicable):
None referenced
## L. Test Principle:
Creatinine in serum or plasma reacts with 3,5-dinitrobenzoic acid under alkaline conditions to form a red color. During the reaction, the reagent layer is completely dissolved and absorbed by the sample-retention layer. These two layers thus form a single detection layer. The intensity of the red chromogen at 550 nm by reflectance spectrophotometry is directly proportional to the creatinine concentration in the sample.
α-amylase in serum or plasma reacts with the substrate, benzylidene-p-nitrophenol-maltotheptaoside (BG₇-pNP) and hydrolyzes it to form Gₙ-pNP (n=1-5). The Gₙ-pNP is rapidly hydrolyzed by the conjugate enzymes, glucoamylase and α-glucosidase, to liberate p-nitrophenol. During the reaction, the reagent layer is completely dissolved and is absorbed by the sample-retention layer. These two layers thus form a single detection layer. The rate, at which the yellow color is generated as measured at 405 nm by reflectance spectrophotometry, is directly proportional to the amylase activity in the sample.
ALP in serum or plasma reacts with the substrate, p-nitrophenylphosphate and hydrolyzes it to p-nitrophenol and phosphate. During the reaction, the reagent layer is completely dissolved and is absorbed by the sample-retention layer. These two layers thus form a single detection layer. The rate, at which the yellow color is generated as measured at 405 nm by reflectance spectrophotometry, is directly proportional to ALP activity in the sample.
## M. Performance Characteristics (if/when applicable):
### 1. Analytical performance:
#### a. Precision/Reproducibility:
Intra-assay precision was assessed by assaying three control samples twenty times in one run. Acceptance criteria is a CV of <5%. Inter-assay precision
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was assessed by assaying three control samples in duplicate in ten runs over five days. Acceptance criteria is a $\mathrm{CV} < 10\%$ . The results are presented in the tables below:
Intra Assay Precision on SpotChem EZ Analyzer
| Analyzer SpotChem | | Level 1 | Level 2 | Level 3 |
| --- | --- | --- | --- | --- |
| Creatinine | N | 20 | 20 | 20 |
| | Mean (mg/dL) | 1.23 | 1.51 | 4.45 |
| | SD | 0.055 | 0.060 | 0.076 |
| | %CV | 4.5 | 4.0 | 1.7 |
| Amylase | Mean (mg/dL) | 69.2 | 298.4 | 506.7 |
| | SD | 3.28 | 13.59 | 10.73 |
| | %CV | 4.7 | 4.6 | 2.1 |
| ALP | Mean (mg/dL) | 59.7 | 223.6 | 431.2 |
| | SD | 1.95 | 7.95 | 14.12 |
| | %CV | 3.3 | 3.6 | 3.3 |
Inter Assay Precision on SpotChem EZ Analyzer
| Analyzer SpotChem | | Level 1 | Level 2 | Level 3 |
| --- | --- | --- | --- | --- |
| Creatinine | Days | 5 | 5 | 5 |
| | n | 20 | 20 | 20 |
| | Mean (mg/dL) | 1.29 | 1.50 | 4.40 |
| | SD | 0.091 | 0.069 | 0.110 |
| | %CV | 7.1 | 4.6 | 2.5 |
| Amylase | Mean (mg/dL) | 69.5 | 290.1 | 494.1 |
| | SD | 2.28 | 7.28 | 18.17 |
| | %CV | 3.3 | 2.5 | 3.7 |
| ALP | Mean (mg/dL) | 58.7 | 222.4 | 425.9 |
| | SD | 1.79 | 5.65 | 16.60 |
| | %CV | 3.0 | 2.5 | 3.9 |
Whole blood samples with known levels of Creatinine, Amylase and ALP were mixed. Ten replicates of each sample within one run. Acceptance criteria is a CV of $< 5\%$ . The results are presented in the table below:
| Analyzer SpotChem | Creatinine | Amylase | ALP |
| --- | --- | --- | --- |
| Mean | 2.66 | 46 | 307.2 |
| Minimum | 2.5 | 43 | 294 |
| Maximum | 2.9 | 49 | 321 |
| Std. Dev | 0.126 | 2.26 | 8.57 |
| % CV | 4.74 | 4.91 | 2.78 |
| Std Error | 0.04 | 0.71 | 2.71 |
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b. Linearity/assay reportable range:
The linearity was assessed by assaying serial dilutions. The linearity claim is based on a percent deviation of ≤ 5% at the two highest analyte concentrations. The results obtained were as follows: Creatinine up to 37.9 mg/dL, Amylase up to 800 IU/L and ALP up to 859.3 IU/L.
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
The calibration set points are fixed by the manufacturer and are unique with each reagent lot and stored on the magnetic card provided with each kit lot.
The principle of the calibration is to fix a two-point calibration curve for a given lot into the memory of the instrument. The sample absorbances are then read off this fixed curve by the instrument and the concentration is calculated and the results are provided by the software.
The magnetic card has values of the basic calibration curve (Cal-Low (a) and Cal-High (b)) and its own measured value (Cal-Low (A) and Cal-High (B)). During calibration, the SpotChem EZ reads these 4 values from magnetic card, and calculates the calibration to be A->a, B->b. To assign A and B: average on n=18 tests x High (for B) and Low (for A) in each lot with Calibrator (A and B indicated value of calibrator).
The value of the calibrator is assigned by the manufacturer by assessing the mean value of 3 lots x n=6 x 5 days x 2 instruments x High (for b) and Low (for a).
Control values are determined using previously cleared control material (k942458). The value assignment protocol is as follows: a minimum of five vials of each control level is required for value assignment. One vial is required for each day and will be tested on three different instruments to produce a minimum of 10 replicates on each instrument. Each instrument will be calibrated each testing day for five testing days.
d. Detection limit:
Functional sensitivity was assessed by diluting a pool to 10 different concentrations below the lower limit of the analyte range. Each dilution was assayed in replicates of ten. The mean, standard deviation and percent coefficient of variation were calculated for the ten replicates of each dilution. The functional sensitivity of the test was defined at the value of the dilution where the CV is approximately 20% (taking into consideration that the actual mean was within ±10% of the expected target). It was determined that functional sensitivity was 0.66 mg/dL with a CV of 7.8% for creatinine, 12.6
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IU/L with a CV of 4.1% for amylase and 25.4 IU/L with a CV of 2.8% for ALP.
e. Analytical specificity:
Studies were performed to assess common or known substances that could interfere with the method. A summary of the data for know interferents appears for the common interferents in the table below:
| | Creatinine | Amylase | ALP |
| --- | --- | --- | --- |
| Sample | Highest Level Tested with No Interference | Highest Level Tested with No Interference | Highest Level Tested with No Interference |
| Hemoglobin | 300 mg/dL | 100 mg/dL | 250 mg/dL |
| Bilirubin | 15.21 mg/dL | 3.16 mg/dL | 7.56 mg/dL |
| Triglycerides | 285 mg/dL | 337.4 mg/dL | 423 mg/dL |
f. Assay cut-off:
Not applicable.
2. Comparison studies:
a. Method comparison with predicate device:
Clinical correlation studies were performed comparing the SpotChem II amylase and ALP results generated on the SpotChem EZ analyzer against the results from the PolyChem Analyzer using serum samples. The creatinine results were generated on the SpotChem EZ analyzer against results from the Vitros 750 creatinine slides using serum samples. The correlations are as follows:
Creatinine y = 0.926x + 0.184, r = 0.997, n = 50, range 0.7–11.8 mg/dL
Amylase y = 1.059x – 6.206, r = 0.998, n = 40, range 17-738 IU/L
ALP y = 0.971x-0.218 r = 0.990, n = 40, range 43-814 IU/L
b. Matrix comparison:
Clinical correlation studies were performed comparing the creatinine, amylase and ALP results generated on the SpotChem EZ analyzer for serum (on the y axis) and whole blood (on the x axis). The correlations are as follows:
Creatinine y = 0.961x + 0.085, r = 0.996, n = 23, range 0.8-10.0 mg/dL
Amylase y = 0.958x +1.393, r = 0.990, n = 20, range 35-138 IU/L
ALP y = 0.998x +2.760, r = 0.992, n = 20, range 34-158 IU/L
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Clinical correlation studies were performed comparing creatinine, amylase and ALP results generated on the SpotChem EZ analyzer for plasma (on the y axis) and whole blood (on the x axis). The correlations are as follows:
Creatinine y = 1.004x + 0.037, r = 0.998, n = 23, range 0.8-9.7 mg/dL
Amylase y = 0.941x + 3.857, r = 0.993, n = 20, range 32-138 IU/L
ALP y = 991x + 1.513, r = 0.990, n = 20, range 35-158 IU/L
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):
4. Clinical cut-off:
Not applicable.
5. Expected values/Reference range:
The following literature reference values are provided;
Creatinine – Adult male 0.7-1.3 mg/dL, 62-115 μmol/L
Adult female 0.6 -1.1 mg/dL, 53 – 97 μmol/L
Amylase – 25-125 IU/L, 0.42 -2.09 μkat/L
ALP – 40-150 IU/L, 0.67 – 2.50 μkat/L
1. Tietz, N.W., Fundamentals of Clinical Chemistry, Second Edition, W.B. Saunders Company, 1976.
2. Tietz, N.W. Textbook of Clinical Chemistry, Second Edition, W.B Saunders Company, 1994
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.
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.