(147 days)
Not Found
No
The device description details a standard immunoassay based on enzyme activity and spectrophotometric measurement. There is no mention of AI, ML, or any computational analysis beyond basic signal processing for absorbance measurement. The performance studies are standard analytical chemistry validations.
No
This device is an immunoassay designed for the detection of hydrocodone and its metabolites in human urine. It provides analytical test results for diagnostic purposes and does not directly provide therapy.
Yes
The intended use explicitly states, "The ARK Hydrocodone Assay is an immunoassay intended for the qualitative detection and/or semi-quantitative estimation of hydrocodone and its metabolites in human urine." This directly describes a diagnostic function.
No
The device description clearly states it is a liquid ready-to-use homogeneous enzyme immunoassay, which is a chemical reagent-based test, not a software-only device.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The intended use explicitly states it's for the "qualitative detection and/or semi-quantitative estimation of hydrocodone and its metabolites in human urine." This is a diagnostic test performed on a biological sample (urine) outside of the body (in vitro).
- Device Description: The description details a "homogeneous enzyme immunoassay" that measures the presence and concentration of hydrocodone in a specimen. This is a common type of in vitro diagnostic test.
- Anatomical Site: The test is performed on "human urine," which is a biological specimen.
- Intended User / Care Setting: It's intended for use in a "Clinical laboratory," which is where IVD tests are typically performed.
- Performance Studies: The document describes performance studies conducted on "clinical urine specimens," further indicating its use in a diagnostic setting.
- Predicate Device: The mention of a "Predicate Device(s)" with a K number (K150502; DRI Hydrocodone Assay) strongly suggests that this device is being compared to a previously cleared IVD device, a standard process for regulatory submission of IVDs.
All these factors align with the definition and characteristics of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
The ARK Hydrocodone Assay is an immunoassay intended for the qualitative detection and/or semi-quantitative estimation of hydrocodone and its metabolites in human urine at a cutoff of 300 ng/mL. The semi-quantitative mode is for the purpose of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method, such as Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS), or (2) permitting laboratories to establish quality control procedures.
The ARK Hydrocodone Assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used in order to obtain a confirmed positive analytical result. Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug test result, particularly when the preliminary test result is positive.
Product codes
DJG
Device Description
The ARK Hydrocodone Assay is supplied as a liquid ready-to-use homogeneous enzyme immunoassay. The assay is based on competition between hydrocodone in the specimen and hydrocodone labeled with recombinant glucose-o-phosphate dehydrogenase (rG6PDH) for antibody binding sites. As the latter binds antibody, enzyme activity decreases. In the presence of hydrocodone from the specimen, enzyme activity increases and is directly related to the hydrocodone concentration. Active enzyme converts nicotinamide adenine dinucleotide (NAD) to NADH in the presence of glucose-6-phosphate (G6P), resulting in an absorbance change that is measured spectrophotometrically. Endogenous G6PDH does not interfere because the coenzyme NAD functions only with the bacterial enzyme used in the assay.
The ARK Hydrocodone Assay consists of reagents R1 anti-hydrocodone monoclonal rabbit antibodies with substrate and R2 hydrocodone derivative labeled with bacterial recombinant G6PDH enzyme.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Clinical laboratory; Prescription use only
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies
Precision studies were performed using CLSI EP05-A3 as a guideline. Drug-free, negative human urine was supplemented with hydrocodone (0 to 600 ng/mL). Each level was assayed in quadruplicate twice a day for 20 days (N=160) and evaluated qualitatively and semiquantitatively.
Analytical Recovery: Drug-free, negative human urine was spiked with hydrocodone across the assay range of the semi-quantitative calibration curve. Each sample was run in replicates of 5 in semi-quantitative mode and the average was used to determine percent recovery compared to the expected value.
Analytical Specificity: All compounds tested were added to drug-free, negative human urine and tested with the ARK Hydrocodone Assay in both qualitative and semi-quantitative modes. The cross-reactivity of hydrocodone and its metabolites was evaluated by spiking these compounds into drug-free, negative human urine and evaluated by dose-response to determine the approximate equivalence to the 300 ng/mL hydrocodone cutoff.
Interference - Endogenous Substances: High concentrations of the following endogenous substances were added into hydrocone-spiked urine (± 25% of the cutoff concentration). No interference was observed when tested with the ARK Hydrocodone Assay.
Interference – Boric Acid: One percent (1%) w/v of boric acid was added into hydrocodone-spiked urine (± 25% of the cutoff concentration).
Specific Gravity: Urine samples with specific gravity values ranging from 1.000 to 1.030 were tested in the presence of the two levels of hydrocodone at ± 25% of the 300 ng/mL cutoff concentration. No interference was observed when tested with the ARK Hydrocodone Assay in both qualitative and semi-quantitative modes.
pH: Urine samples with pH values from 3.0 to 11.0 were tested in the presence of the two levels of hydrocodone at ± 25% of the 300 ng/mL cutoff concentration. No interference was observed when tested with the ARK Hydrocodone Assay in both qualitative and semi-quantitative modes.
Method Comparison: Two hundred twenty-six (226) unaltered clinical urine specimens that are not individually identifiable were analyzed by ARK Hydrocodone Assay in both qualitative and semi-quantitative modes and the results were compared to LC-MS/MS. The overall concordance between LC-MS/MS and the ARK Hydrocodone Assay was 92.5%. Seventeen (17) samples were considered discordant relative to the ARK Hydrocodone 300 ng/mL cutoff. Cross-reactivity to the major metabolite hydromorphone contributed to the positive results for samples with 100,000, Cross-reactivity (%): 450 ng/mL): 66
ARK Hydrocodone Assay Results: Negative
450 ng/mL): 0
Semi-quantitative method comparison with LC-MS/MS as reference method (overall concordance 92.5%):
ARK Hydrocodone Assay Results: Positive
450 ng/mL): 66
ARK Hydrocodone Assay Results: Negative
450 ng/mL): 0
Predicate Device(s)
DRI Hydrocodone Assay (K150502)
Reference Device(s)
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information
Not Found
§ 862.3650 Opiate test system.
(a)
Identification. An opiate test system is a device intended to measure any of the addictive narcotic pain-relieving opiate drugs in blood, serum, urine, gastric contents, and saliva. An opiate is any natural or synthetic drug that has morphine-like pharmocological actions. The opiates include drugs such as morphine, morphine glucoronide, heroin, codeine, nalorphine, and meperedine. Measurements obtained by this device are used in the diagnosis and treatment of opiate use or overdose and in monitoring the levels of opiate administration to ensure appropriate therapy.(b)
Classification. Class II (special controls). An opiate test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).
0
Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). The logo consists of two parts: the Department of Health & Human Services logo on the left and the FDA acronym along with the full name of the agency on the right. The FDA part of the logo is in blue, with the acronym in a square and the full name written out to the right of it.
ARK Diagnostics, Inc. Thomas Houts, Ph.D. Sr. Director, Quality, Regulatory and Planning 48089 Fremont Boulevard Fremont, California 94538
Re: K231752
Trade/Device Name: ARK Hydrocodone Assay Regulation Number: 21 CFR 862.3650 Regulation Name: Opiate Test System Regulatory Class: Class II Product Code: DJG Dated: October 6, 2023 Received: October 6, 2023
Dear Thomas Houts:
We have reviewed your section 510(k) premarket notification of intent to market the device referenced above and 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 (the Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database available at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Additional information about changes that may require a new premarket notification are provided in the FDA guidance documents entitled "Deciding When to Submit a 510(k) for a Change to an Existing Device" (https://www.fda.gov/media/99812/download) and "Deciding When to Submit a 510(k) for a Software Change to an Existing Device" (https://www.fda.gov/media/99785/download).
1
Your device is also subject to, among other requirements, the Quality System (QS) regulation (21 CFR Part 820), which includes, but is not limited to, 21 CFR 820.30, Design controls; 21 CFR 820.90, Nonconforming product; and 21 CFR 820.100, Corrective and preventive action. Please note that regardless of whether a change requires premarket review, the QS regulation requires device manufacturers to review and approve changes to device design and production (21 CFR 820.30 and 21 CFR 820.70) and document changes and approvals in the device master record (21 CFR 820.181).
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR Part 803) for devices or postmarketing safety reporting (21 CFR Part 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safetyreporting-combination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR Part 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR Parts 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely, Joseph A. Digitally signed by Kotarek -S Date: 2023.11.09 Joseph Kotarek, Ph.D. Toxicology Branch Chief Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known) K231752
Device Name ARK Hydrocodone Assay
Indications for Use (Describe)
The ARK Hydrocodone Assay is an immunoassay intended for the qualitative detection and/or semi-quantitative estimation of hydrocodone and its metabolites in human urine at a cutoff of 300 ng/mL. The semi-quantitative mode is for the purpose of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method, such as Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS), or (2) permitting laboratories to establish quality control procedures.
The ARK Hydrocodone Assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used in order to obtain a confirmed positive analytical result. Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug test result, particularly when the preliminary test result is positive.
Type of Use (Select one or both, as applicable)
| ☑ Prescription Use (Part 21 CFR 801 Subpart D) |
|---|
| ☐ Over-The-Counter Use (21 CFR 801 Subpart C) |
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
3
Section 05: 510(k) SUMMARY
This 510(k) Summary of Safety and Effectiveness information is being submitted in accordance with the requirements of Safe Medical Device Act of 1990 and 21 CFR 807.92.
The assigned 510(k) number is K231752.
| 807.92 (a)(1): Name: | ARK Diagnostics, Inc. |
|---|---|
| Address: | 48089 Fremont Blvd |
| Fremont, CA 94538 USA | |
| Owner Operator Number: | 10027663 |
| Establishment Registration: | 3005755244 |
| Phone: | (510) 270-6270 |
| FAX: | (510) 270-6298 |
| Contact: | Thomas Houts, Ph.D., FAACC |
| ARK Diagnostics, Inc. | |
| Director, Quality, Regulatory and Planning | |
| Telephone: (510) 270-6296 | |
| E-mail: tom@ark-tdm.com |
Date Prepared: June 5, 2023
807.92 (a)(2): Device Name – Trade Name, Common Name, and Classification
| Trade Name: | ARK Hydrocodone Assay |
|---|---|
| Common Name: | Homogeneous Enzyme Immunoassay, Opiate Test System |
| Classification: |
| Product Code | Classification | Regulation Section | Panel |
|---|---|---|---|
| DJG | Class II | 21 CFR 862.3650 | |
| Opiate Test System | Toxicology | ||
| (91) |
807.92 (a)(3): Identification of the Legally Marketed Predicate Device
DRI Hydrocodone Assay (K150502)
4
807.92 (a)(4): Device Description
The ARK Hydrocodone Assay is supplied as a liquid ready-to-use homogeneous enzyme immunoassay. The assay is based on competition between hydrocodone in the specimen and hydrocodone labeled with recombinant glucose-o-phosphate dehydrogenase (rG6PDH) for antibody binding sites. As the latter binds antibody, enzyme activity decreases. In the presence of hydrocodone from the specimen, enzyme activity increases and is directly related to the hydrocodone concentration. Active enzyme converts nicotinamide adenine dinucleotide (NAD) to NADH in the presence of glucose-6-phosphate (G6P), resulting in an absorbance change that is measured spectrophotometrically. Endogenous G6PDH does not interfere because the coenzyme NAD functions only with the bacterial enzyme used in the assay.
The ARK Hydrocodone Assay consists of reagents R1 anti-hydrocodone monoclonal rabbit antibodies with substrate and R2 hydrocodone derivative labeled with bacterial recombinant G6PDH enzyme.
807.92 (a)(5): Intended Use / Indications for Use
ARK Hydrocodone Assay
The ARK Hydrocodone Assay is an immunoassay intended for the qualitative detection and/or semi-quantitative estimation of hydrocodone and its metabolites in human urine at a cutoff of 300 ng/mL.
The semi-quantitative mode is for the purpose of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method, such as Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS), or (2) permitting laboratories to establish quality control procedures.
The ARK Hydrocodone Assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used in order to obtain a confirmed positive analytical result. Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/tandem Mass Spectrometry (LC-MS/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug test result, particularly when the preliminary test result is positive.
5
807.92 (a)(6): Technological Similarities and Differences to the Predicate
SUBSTANTIAL EQUIVALENCE COMPARATIVE TABLE
Comparison between the DRI Hydrocodone Assay and the ARK Hydrocodone Assay
| Characteristic | Predicate Device | Candidate Device |
|---|---|---|
| Similarities | ||
| Test System | Homogenous enzyme immunoassay | |
| (HEIA) | Same | |
| Intended Use | The DRI® Hydrocodone Assay is | |
| intended for the qualitative and semi- | ||
| quantitative detection and estimation | ||
| of Hydrocodone and its metabolites in | ||
| human urine at a cutoff of 300 ng/mL. |
The semi-quantitative mode is for
purposes of enabling laboratories to
determine an appropriate dilution of
specimen for confirmation by a
confirmatory method such as LC-
MS/MS or GCMS and permitting
laboratories to
establish quality control measures.
This assay provides a preliminary
analytical test result. A more specific
alternative chemical method must be
used in order to
confirm an analytical result. Gas
chromatography/mass spectrometry
(GC/MS) and Liquid
Chromatography/tandem mass
spectrometry (LC-MS/MS) are the
preferred confirmatory methods.
Clinical consideration and
professional judgment
should be applied to any drug of
abuse test result, particularly when
preliminary positive results are used. | Same |
| Sample Matrix | Human urine | Same |
| User Environment | Clinical laboratory; Prescription use
only | Same |
| Mass
Spectrometry
Confirmation | Required to confirm preliminary
positive analytical results | Same |
| Platform Required | Automated clinical chemistry
analyzer | Same |
| Reagents Form | Liquid - Ready-to-use | Same |
| Reagent Materials | Two (2) reagent system:
Antibody/substrate reagent (mouse
monoclonal antibodies to
hydrocodone) and enzyme labeled
conjugate (hydrocodone derivative
labeled with enzyme)
Sodium azide preservative | Two (2) reagent system:
Antibody/substrate reagent (rabbit
monoclonal antibodies to
hydrocodone) and enzyme labeled
conjugate (hydrocodone derivative
labeled with enzyme)
Sodium azide preservative |
| Quality Controls | Two levels - 225 and 375 ng/mL | Same |
| Storage | 2-8°C until expiration date | Same |
| Measured Analyte | Hydrocodone | Same |
| Detection | Absorbance change measured
spectrophotometrically at 340 nm | Same |
| Cutoff Level | 300 ng/mL | Same |
| Control Levels | 225 and 375 ng/mL | Same |
6
| Characteristic | Predicate Device
DRI Hydrocodone Assay (K150502) | Candidate Device
ARK Hydrocodone Assay |
|-------------------|-----------------------------------------------------|-------------------------------------------|
| Differences | | |
| Antibody | Mouse monoclonal | Rabbit monoclonal |
| Calibrator Levels | 0, 100, 300, 500, 1000 ng/mL | 0, 50, 100, 300, 800 ng/mL |
7
807.92 (b)(1) and 807.92 (b)(2): Brief Description of Nonclinical and Clinical Data
The following performance characteristics were obtained on the Beckman Coulter AU680® automated clinical chemistry analyzer.
Precision
Precision studies were performed using CLSI EP05-A3 as a guideline. Drug-free, negative human urine was supplemented with hydrocodone (0 to 600 ng/mL). Each level was assayed in quadruplicate twice a day for 20 days (N=160) and evaluated qualitatively and semiquantitatively. Results are summarized in the tables below.
| Hydrocodone
(ng/mL) | Relative %
Cutoff | # of Results | Precision Results |
|------------------------|----------------------|--------------|---------------------|
| 0 | -100 | 160 | 160 Neg |
| 75 | -75 | 160 | 160 Neg |
| 150 | -50 | 160 | 160 Neg |
| 225 | -25 | 160 | 160 Negative |
| 300 | Cutoff | 160 | 50 Neg /
110 Pos |
| 375 | +25 | 160 | 160 Pos |
| 450 | +50 | 160 | 160 Pos |
| 525 | +75 | 160 | 160 Pos |
| 600 | +100 | 160 | 160 Pos |
Qualitative Precision
Semi-quantitative Precision
| Hydrocodone
(ng/mL) | Relative
%
Cutoff | # of
Results | Mean
(ng/mL) | Precision
Results |
|------------------------|-------------------------|-----------------|-----------------|----------------------|
| 0 | -100 | 160 | 0 | 160 Neg |
| 75 | -75 | 160 | 78 | 160 Neg |
| 150 | -50 | 160 | 142 | 160 Neg |
| 225 | -25 | 160 | 229 | 160 Neg |
| 300 | Cutoff | 160 | 314 | 24 Neg /
136 Pos |
| 375 | +25 | 160 | 388 | 160 Pos |
| 450 | +50 | 160 | 459 | 160 Pos |
| 525 | +75 | 160 | 539 | 160 Pos |
| 600 | +100 | 160 | 620 | 160 Pos |
8
Analytical Recovery
Drug-free, negative human urine was spiked with hydrocodone across the assay range of the semi-quantitative calibration curve. Each sample was run in replicates of 5 in semi-quantitative mode and the average was used to determine percent recovery compared to the expected value.
| Expected Value
(ng/mL) | Observed Value
(ng/mL) | Recovery (%) |
|---------------------------|---------------------------|--------------|
| 0 | 0 | N/A |
| 80 | 80 | 99 |
| 160 | 151 | 94 |
| 240 | 247 | 103 |
| 320 | 322 | 101 |
| 400 | 386 | 96 |
| 480 | 472 | 98 |
| 560 | 537 | 96 |
| 640 | 606 | 95 |
| 720 | 621 | 86 |
| 800 | 738 | 92 |
Analytical Specificity
All compounds tested were added to drug-free, negative human urine and tested with the ARK Hydrocodone Assay in both qualitative and semi-quantitative modes.
The cross-reactivity of hydrocodone and its metabolites was evaluated by spiking these compounds into drug-free, negative human urine and evaluated by dose-response to determine the approximate equivalence to the 300 ng/mL hydrocodone cutoff. These concentrations were used to determine the percent cross-reactivity according to the formula:
% Cross-reactivity = (Cutoff concentration / Concentration approximately equivalent to the 300 ng/mL cutoff) X 100
For compounds that did not produce a positive result, the highest concentration tested was used to calculate percent cross-reactivity.
9
| Compound | Concentration
Approximately
Equivalent to the
Cutoff
(ng/mL) | Cross-reactivity (%) |
|------------------------------|--------------------------------------------------------------------------|----------------------|
| Hydrocodone | 292 | 103 |
| Hydromorphone | 299 | 100 |
| Hydromorphone-3β-Glucuronide | 45,439 | 0.7 |
| Norhydrocodone | 2,277 | 13.2 |
| Dihydrocodeine | >100,000 | 450 ng/mL) |
|-------------------------------------|----------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|
| Positive | 8* | 8* | 9 | 66 |
| Negative | 134 | 0 | 1* | 0 |
Semi-quantitative method comparison with LC-MS/MS as reference method
| ARK
Hydrocodone
Assay Results | 450 ng/mL) |
|-------------------------------------|----------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------|
| Positive | 8* | 8* | 9 | 66 |
| Negative | 134 | 0 | 1* | 0 |
*Discordant Results
15
| Sample # | ARK
Qualitative
(POS/NEG) | LC-MS/MS (ng/mL) | | | ARK
Semi-
quantitative
(ng/mL) |
|----------|---------------------------------|------------------|---------------|-------------------|-----------------------------------------|
| | | Hydrocodone | Hydromorphone | Adjusted
Total | |
| 3 | POS | 287.8 | 210.0 | 497.8 | 476.0 |
| 15 | POS | 226.9 | 150.5 | 377.4 | 390.0 |
| 18 | POS | 156.0 | 174.7 | 330.8 | 335.2 |
| 23 | POS | 5.4 | 1317.7 | 1323.1 | 387.7 |
| 38 | NEG | 306.5 | 22.4 | 328.9 | 277.6 |
| 39 | POS | 162.0 | 52.4 | 214.5 | 316.1 |
| 48 | POS | 200.5 | 61.7 | 262.2 | 358.4 |
| 51 | POS | 174.4 | 29.0 | 203.4 | 357.4 |
| 66 | POS | 146.7 | 190.3 | 337.0 | 463.1 |
| 68 | POS | 181.2 | 150.3 | 331.5 | 382.2 |
| 70 | POS | Not Detected | 545.7 | 545.7 | 445.7 |
| 75 | POS | 5.9 | 10524.1 | 10530.0 | 2549.1 |
| 86 | POS | 255.8 | 30.7 | 286.5 | 471.4 |
| 90 | POS | 106.5 | 214.0 | 320.4 | 335.5 |
| 97 | POS | Not Detected | 1769.8 | 1769.8 | 501.3 |
| 99 | POS | Not Detected | 706.1 | 706.1 | 657.9 |
| 101 | POS | Not Detected | 5461.7 | 5461.7 | 2014.2 |
Seventeen (17) samples were considered discordant relative to the ARK Hydrocodone 300 ng/mL cutoff. Cross-reactivity to the major metabolite hydromorphone contributed to the positive results for samples with