For the quantitative determination of folate in serum or EDTA plasma and red blood cells using the Folate BA (Biotin Avidin) assay on the Chiron Diagnostics ACS:180® Automated Chemiluminescence Systems.
Device Story
The Chiron Diagnostics ACS:180 Folate assay is an in vitro diagnostic test used on the ACS:180 Automated Chemiluminescence System. It measures folate levels in serum, EDTA plasma, or red blood cells. The assay uses a competitive chemiluminescent immunoassay principle: patient folate competes with acridinium ester-labeled folate for binding to biotin-labeled folate binding protein, which is captured by avidin-coupled paramagnetic particles. The system automates sample pretreatment, reagent dispensing, incubation, washing, and signal detection. The device outputs relative light units (RLUs), which are inversely proportional to the folate concentration in the sample. Used in clinical laboratories by trained technicians, the results assist healthcare providers in the differential diagnosis of macrocytic anemias and the assessment of folate status, facilitating appropriate clinical treatment for deficiencies.
Clinical Evidence
Bench testing only. Performance evaluated using 263 serum and 109 red blood cell samples to establish reference ranges. Analytical sensitivity is 0.25 ng/mL. Method comparison against an alternate chemiluminescent method showed high correlation (r=0.95 for serum, r=0.96 for RBC). Precision studies (n=138 per sample) demonstrated within-run CVs of 4.88-7.95% and total CVs of 5.36-9.24%.
Technological Characteristics
Competitive chemiluminescent immunoassay. Components: acridinium ester-labeled folate, biotin-labeled folate binding protein, avidin-coupled paramagnetic particles. Automated system performs sample pretreatment, incubation at 37°C, magnetic separation, and chemiluminescent detection. Connectivity: integrated with ACS:180 Automated Chemiluminescence System. No specific material standards or software architecture details provided.
Indications for Use
Indicated for the quantitative determination of folate in serum, EDTA plasma, and red blood cells to aid in the assessment of folate status in patients suspected of folate deficiency, including those with macrocytic anemia, malabsorption, or dietary deficiencies.
Regulatory Classification
Identification
A folic acid test system is a device intended to measure the vitamin folic acid in plasma and serum. Folic acid measurements are used in the diagnosis and treatment of megaloblastic anemia, which is characterized by the presence of megaloblasts (an abnormal red blood cell series) in the bone marrow.
Predicate Devices
Chiron Diagnostics ACS: 180 Folate Immunoassay
Submission Summary (Full Text)
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JUN 30 1999
Company Confidential
K991582
# Summary of Safety and Effectiveness
As required by 21 CFR 807.92, the following 510(k) Summary is provided:
# 1. Submitters Information
| Contact person: | William J. Pignato<br>Director of Regulatory Affairs |
|-------------------------|-------------------------------------------------------------------------|
| Address: | Chiron Diagnostics Corporation<br>63 North Street<br>Medfield, MA 02052 |
| Phone:<br>Fax<br>e-mail | (508) 359-3825<br>(508) 359-3356<br>william.pignato.b@bayer.com |
April 30, 1999 Date Summary Prepared:
#### 2. Device Information
| Proprietary Name: | Chiron Diagnostics ACS: 180 Folate |
|------------------------|------------------------------------|
| Common Name: | Folate Immunological test system |
| Device Classification: | Class II |
#### 3. Predicate Device Information
| Name: | Chiron Diagnostics ACS: 180 Folate Immunoassay |
|---------------|------------------------------------------------|
| Manufacturer: | Chiron Diagnostics Corporation |
## 4. Device Description
Folate, with vitamin B12, is essential for DNA synthesis, which is required for normal red blood cell maturation. Humans obtain folate from dietary sources including fruits, green and leafy vegetables, yeast, and organ meats. Folate is absorbed through the small intestine and stored in the liver.
Low folate intake, malabsorption as a result of qastrointestinal diseases, pregnancy, and drugs such as phenytoin are causes of folate deficiency. Folate deficiency is also associated with chronic alcoholism. Folate and vitamin B12 deficiency impair DNA synthesis, causing macrocytic anemias. These anemias are characterized by abnormal maturation of red blood cell precursors in the bone marrow, the presence of megaloblasts, and decreased red blood cell survival.
Since both folate and vitamin B12 deficiency can cause macrocytic anemia, appropriate treatment depends on the differential diagnosis of the deficiency. Serum folate measurement provides an early index of folate status. However, folate is much more concentrated in red blood cells than in serum so the red blood cell folate measurement
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more closely reflects tissue stores. Red blood cell folate concentration is considered the most reliable indicator of folate status.
### 5. Statement of Intended Use
For the quantitative determination of folate in serum or EDTA plasma and red blood cells using the Folate BA (Biotin Avidin) assay on the Chiron Diagnostics ACS:180® Automated Chemiluminescence Systems.
### 6. Summary of Technological Characteristics
The Chiron Diagnostics ACS:180 Folate assay is a competitive immunoassay using direct chemiluminescent technology. Folate in the patient sample competes with acridinium esterlabeled folate in the Lite Reagent for a limited amount of biotin-labeled folate binding protein. Biotin-labeled folate binding protein binds to avidin which is covalently coupled to paramagnetic particles in the Solid Phase. In the ACS:180 Folate assay the sample is pretreated to release the folate from endogenous binding proteins in the sample.
The system performs the following steps for calibrators, quality control samples, and patient samples:
dispenses 150 uL of sample into a cuvette
dispenses 50 µL of DTT
dispenses 100 µL of folate binding protein and 200 µL of Solid Phase and incubates for 5.0 minutes at 37°C
dispenses 100 µL of Lite Reagent and incubates for 2.5 minutes at 37°C
separates, aspirates, and washes the cuvettes with reagent water6
dispenses 300 uL each of Reagent 1 and Reagent 2 to initiate the chemiluminescent reaction
reports results according to the selected option, as described in the system operating instructions or in the online help system
An inverse relationship exists between the amount of folate present in the patient sample and the amount of relative light units (RLUs) detected by the system.
## 6. Performance Characteristics
## Expected Results
To determine the reference range for the ACS:180 Folate assay for serum and RBC folate, data was obtained on 263 serum and 109 red blood cell folate samples, respectively. The normal ranges are based on 95% confidence intervals and the deficient ranges represent the observed ranges.
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#### Company Confidential
| Category | N | Mean<br>(ng/mL) | Range<br>(ng/mL) | Mean<br>(nmol/L) | Range<br>(nmol/L) |
|---------------|-----|-----------------|------------------|------------------|-------------------|
| <i>Serum</i> | | | | | |
| <i>folate</i> | | | | | |
| deficient* | 32 | 1.08 | 0.0-2.31 | 2.45 | 0.0-5.24 |
| normal | 231 | 9.89 | 4.25-23.8 | 22.4 | 9.65-54.0 |
| <i>RBC</i> | | | | | |
| <i>folate</i> | | | | | |
| deficient* | 10 | 64.4 | 9-157 | 146 | 20.4-356 |
| normal | 99 | 545 | 322-886 | 1237 | 731-2011 |
* Diagnosed by bone and/or peripheral blood smear pathology and other criteria including:
- megaloblastic anemia
- . folate deficient diet
- malabsorption
- alcoholism ●
- . Tropical Sprue
- . abnormal blood parameters including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and hematocrit (HCT).
Laboratories should consider these reference ranges as guidelines only. The data was obtained on apparently healthy males and females from the United States. Due to population demographic factors, assay methods, calibration, and reagent specificity, each laboratory should establish its own reference ranges for the diagnostic evaluation of patient results.
#### Sensitivity and Assay Reportable Range
The ACS:180 Folate assay measures folate concentrations up to 20 ng/mL (45.4 nmol/L) with a minimum detectable concentration of 0.25 ng/mL (0.6 nmol/L). Analytical sensitivity is defined as the concentration of folate that corresponds to the RLUs that are two standard deviations less than the mean RLUs of 20 replicate determinations of the folate zero standard in 7 assays with 3 lots of reagents.
#### Method Comparison
For 258 serum samples in the range of 0 to 20 ng/mL (0 to 45.4 nmol/L), the relationship between the ACS:180 Folate assay and an alternate folate assay is described by the equation:
ACS:180 Folate = 0.92 (alternate chemiluminescent method) + 0.21 ng/mL Correlation coefficient (r) = 0.95
For 189 red blood cell samples in the range of 9.0 to 882 ng/mL (20.4 to 2002 nmoV/L), the relationship between the ACS:180 Folate assay and an alternate folate assay is described by the equation:
ACS:180 RBC Folate = 0.93 (alternate chemiluminescent method) + 52.8 ng/mL Correlation coefficient (r) = 0.96
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# Precision
Four samples were assayed six times with three lots of reagents in 23 runs on four systems (n = 138 for each sample), over a period of three days. The following results were obtained:
| Mean Folate (ng/mL) | Mean Folate (nmol/L) | Within-run % CV | Total % CV |
|---------------------|----------------------|-----------------|------------|
| 1.91 | 4.34 | 7.95 | 9.24 |
| 5.94 | 13.5 | 5.36 | 8.79 |
| 10.6 | 24.1 | 5.61 | 6.60 |
| 15.4 | 35.0 | 4.88 | 5.36 |
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Image /page/4/Picture/1 description: The image shows the seal of the Department of Health & Human Services (HHS). The seal features a stylized eagle with three lines forming its body and wings. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
JUN 30 1999
Mr. William J. Pignato Director of Regulatory Affairs Chiron Diagnostics Corporation 63 North Street Medfield, Massachusettes 02052-1688
K991582 Re:
> Trade Name: Chiron Diagnostics ACS: 180® Folate Assay Regulatory Class: II Product Code: CGN, JIS Dated: April 30, 1999 Received: May 7, 1999
Dear Mr. Pignato:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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#### Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Steven Sutman
Steven I. Gutman, M.D. M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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Company Confidential
Page | of |
510(k) Number (if known): K991682
Device Name: Chiron Diagnostics ACS:180 Folate Assay
Indications for Use:
For the quantitative determination of folate in serum or EDTA plasma and red blood cells using the Folate BA (Biotin Avidin) assay on the Chiron Diagnostics ACS: 180® Automated Chemiluminescence Systems.
Dean Cooper
(Division Sign-Off)
vision of Clinical Lab ratory Devices 510(k) Number
(PLEASE DO NOT WRITE BELOW THIS LINE--CONTINUE ON ANOTHER PAGE, IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use (Per 21 CFR 801.109)
OR
Over-The-Counter Use (Optional Format 1-2-96)
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.