K253082 · Lin-Zhi International, Inc. · DJG · Jan 16, 2026 · Clinical Toxicology
Device Facts
Record ID
K253082
Device Name
LZI Buprenorphine II Enzyme Immunoassay
Applicant
Lin-Zhi International, Inc.
Product Code
DJG · Clinical Toxicology
Decision Date
Jan 16, 2026
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 862.3650
Device Class
Class 2
Indications for Use
The LZI Buprenorphine II Enzyme Immunoassay is intended for the qualitative and semi-quantitative determination of norbuprenorphine in human urine at the cutoff value of 5 ng/mL when calibrated against norbuprenorphine. The assay is designed for prescription use with a number of automated clinical chemistry analyzers. The semi-quantitative mode is for purposes of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS) or (2) permitting laboratories to establish quality control procedures The assay provides only a preliminary analytical result. A more specific alternative chemical method (e.g., gas or liquid chromatography and mass spectrometry) must be used in order to obtain a confirmed analytical result. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary test result is positive.
Device Story
LZI Buprenorphine II Enzyme Immunoassay is a homogeneous enzyme immunoassay for detecting norbuprenorphine in human urine. Kit includes two reagents (R1: antibody, G6P, NAD; R2: G6PDH-labeled norbuprenorphine). Principle: competitive binding between sample drug and enzyme-labeled drug for fixed antibody; enzyme activity inversely proportional to drug concentration. Active enzyme converts NAD to NADH, measured spectrophotometrically at 340 nm. Used in clinical laboratories on automated chemistry analyzers by trained personnel. Provides preliminary analytical results; requires confirmation by GC/MS or LC/MS. Assists clinicians in drug abuse screening and monitoring.
Clinical Evidence
Bench testing only. Precision/reproducibility evaluated over 22 days (N=88). Linearity confirmed with 99.6%-106.3% recovery. Analytical specificity tested against various drugs and metabolites; cross-reactivity observed with buprenorphine and its glucuronides. Interference testing performed for pH (3-11), specific gravity (1.000-1.030), and common endogenous/exogenous substances. Method comparison study conducted on 94 clinical samples using Beckman Coulter AU480, with results confirmed by LC/MS.
Indicated for qualitative and semi-quantitative determination of norbuprenorphine in human urine at 5 ng/mL cutoff. For prescription use in clinical laboratories using automated clinical chemistry analyzers. Requires confirmatory testing by GC/MS or LC/MS for positive results.
Regulatory Classification
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.
Special Controls
*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).
Predicate Devices
LZI Buprenorphine Enzyme Immunoassay (k090844)
Submission Summary (Full Text)
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FDA
U.S. FOOD & DRUG
ADMINISTRATION
# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY
ASSAY ONLY
## I Background Information:
A 510(k) Number
K253082
B Applicant
Lin-Zhi International, Inc
C Proprietary and Established Names
Proprietary name: LZI Buprenorphine II Enzyme Immunoassay
Common name: Homogeneous Buprenorphine Enzyme Immunoassay
D Regulatory Information
| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| DJG | II | 21 CFR 862.3650 | 91-Toxicology |
## II Submission/Device Overview:
A Purpose for Submission:
Modification to previously cleared assay
B Measurand:
Norbuprenorphine (buprenorphine metabolite)
C Type of Test:
Homogeneous enzyme immunoassay – qualitative and semi-quantitative
## III Intended Use/Indications for Use:
A Intended Use(s):
See Indications for Use below.
B Indication(s) for Use: The LZI Buprenorphine II Enzyme Immunoassay is intended for the qualitative and semi-quantitative determination of norbuprenorphine in human urine at the cutoff
Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993-0002
www.fda.gov
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value of 5 ng/mL when calibrated against norbuprenorphine. The assay is designed for prescription use with a number of automated clinical chemistry analyzers.
The semi-quantitative mode is for purposes of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS) or (2) permitting laboratories to establish quality control procedures
The assay provides only a preliminary analytical result. A more specific alternative chemical method (e.g., gas or liquid chromatography and mass spectrometry) must be used in order to obtain a confirmed analytical result. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary test result is positive.
## C Special Conditions for Use Statement(s):
The assay is for prescription use.
## D Special Instrument Requirements:
Automated clinical chemistry analyzers. (Performance in the studies submitted in the 510(k) are based on the Beckman Coulter AU480 Analyzer.
## IV Device/System Characteristics:
### A Device Description:
The LZI Buprenorphine II Enzyme Immunoassay is a kit comprised of two reagents, R1 and R2, which are bottled separately but sold together within the kit.
The R1 solution contains mouse monoclonal anti-norbuprenorphine antibody, glucose-6-phosphate (G6P), nicotinamide adenine dinucleotide (NAD), stabilizers, and sodium azide (0.09%) as a preservative. The R2 solution contains glucose-6-phosphate dehydrogenase (G6PDH) labeled with norbuprenorphine in buffer with sodium azide (0.09%) as a preservative.
### B Principle of Operation:
The LZI Buprenorphine II Enzyme Immunoassay is a homogeneous enzyme immunoassay ready-to-use liquid reagent. The assay is based on competition between drug in the sample and drug labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for a fixed amount of antibody in the reagent. Enzyme activity decreases upon binding to the antibody, and the drug concentration in the sample is measured in terms of enzyme activity. In the absence of drug in the sample, norbuprenorphine-labeled G6PDH conjugate is bound to antibody, and the enzyme activity is inhibited. On the other hand, when drug is present in the sample, antibody would bind to free drug; the unbound norbuprenorphine-labeled G6PDH then exhibits its maximal enzyme activity. Active enzyme converts nicotinamide adenine dinucleotide (NAD) to NADH, resulting in an absorbance change that can be measured spectrophotometrically at 340 nm.
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V Substantial Equivalence Information:
A Predicate Device Name(s): LZI Buprenorphine Enzyme Immunoassay
B Predicate 510(k) Number(s): k090844
C Comparison with Predicate(s):
| Device & Predicate Device(s): | K253082 | K090844 |
| --- | --- | --- |
| Device Trade Name | LZI Buprenorphine II Enzyme Immunoassay | LZI Buprenorphine Enzyme Immunoassay |
| General Device Characteristic Similarities | | |
| Intended Use | For the qualitative and semi-quantitative determination of norbuprenorphine in human urine at the cutoff value of 5 ng/mL when calibrated against norbuprenorphine. The assay is designed for prescription use with a number of automated clinical chemistry analyzers.
The assay provides only a preliminary analytical result. A more specific alternative chemical method (e.g., gas or liquid chromatography and mass spectrometry) must be used in order to obtain a confirmed analytical result. | Same |
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| Analyte | norbuprenorphine | Same |
| --- | --- | --- |
| Matrix | Urine | Same |
| Storage | 2-8 °C until expiration date | Same |
| Detection | Absorbance change measured spectrophotometrically at 340 nm | Same |
| User Environment | Clinical laboratories: 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 |
| General Device Characteristic Differences | | |
| Cutoff | 5 ng/mL | 5 ng/mL and 10 ng/mL |
| Instrument for performance validation | Beckman Coulter AU480 | Hitachi 717 |
| Calibrator Level | 0, 2.5, 5, 10, and 20 ng/mL | 0, 5, 10, 20, 40, and 75 ng/mL |
| Controls Level | 5 ng/mL Cutoff: 2 Levels: 3.75 and 6.25 ng/mL
10 ng/mL Cutoff: 2 Levels 7 and 13 ng/mL | 5 ng/mL Cutoff: 2 Levels: 3 and 7 ng/mL
10 ng/mL Cutoff: 2 Levels 7 and 13 ng/mL |
VI Standards/Guidance Documents Referenced:
No device-specific guidance documents or special controls are applicable to the LZI Buprenorphine II Enzyme Immunoassay under the classification regulation 21 CFR 862.3650 (Product Code: DJG).
VII Performance Characteristics (if/when applicable):
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All 510(k) studies below were conducted on the Beckman Coulter AU480 Analyzer
A Analytical Performance:
1. Precision/Reproducibility:
Spiked samples of norbuprenorphine were prepared in a urine matrix at the concentrations shown in the table below, and were measured, 2 runs per day, with 2 replicates per run, for 22 days.
Results are tabulated below:
Precision: 5 ng/mL Cutoff
Semi-Quantitative Positive/Negative Results:
| 5 ng/mL Cutoff Result: | | Within Run (N=22) | | Total Precision (N=88) | |
| --- | --- | --- | --- | --- | --- |
| Norbuprenorphine Concentration | % of Cutoff | Number of Determination | Immunoassay Result | Number of Determination | Immunoassay Result |
| 0 ng/mL | 0% | 22 | 22 Negative | 88 | 88 Negative |
| 1.25 ng/mL | 25% | 22 | 22 Negative | 88 | 88 Negative |
| 2.5 ng/mL | 50% | 22 | 22 Negative | 88 | 88 Negative |
| 3.75 ng/mL | 75% | 22 | 22 Negative | 88 | 88 Negative |
| 5 ng/mL | 100% | 22 | 22 Positive | 88 | 2 Neg / 86 Pos |
| 6.25 ng/mL | 125% | 22 | 22 Positive | 88 | 88 Positive |
| 7.5 ng/mL | 150% | 22 | 22 Positive | 88 | 88 Positive |
| 8.75 ng/mL | 175% | 22 | 22 Positive | 88 | 88 Positive |
| 10 ng/mL | 200% | 22 | 22 Positive | 88 | 88 Positive |
Semi-Quantitative Precision Analysis Summary (ng/mL):
| Norbuprenorphine concentration | Within Run (N=22) | | Total Precision (N=88) | |
| --- | --- | --- | --- | --- |
| | SD | %CV | SD | %CV |
| 0 ng/mL | 0.15 | N/A | 0.2 | N/A |
| 1.25 ng/mL | 0.17 | 12.0% | 0.21 | 14.6% |
| 2.5 ng/mL | 0.17 | 6.4% | 0.24 | 8.8% |
| 3.75 ng/mL | 0.19 | 4.7% | 0.28 | 6.9% |
| 5 ng/mL | 0.19 | 3.5% | 0.24 | 4.4% |
| 6.25 ng/mL | 0.19 | 2.8% | 0.27 | 4.0% |
| 7.5 ng/mL | 0.2 | 2.5% | 0.24 | 3.0% |
| 8.75 ng/mL | 0.21 | 2.2% | 0.26 | 2.8% |
| 10 ng/mL | 0.3 | 2.8% | 0.36 | 3.4% |
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Qualitative Positive/Negative Results:
| 5 ng/mL Cutoff Result: | | 5 ng/mL Cutoff Result: | | Total Precision (N=88) | |
| --- | --- | --- | --- | --- | --- |
| Norbuprenorphine Concentration | % of Cutoff | Number of Determination | Immunoassay Result | Number of Determination | Immunoassay Result |
| 0 ng/mL | 0% | 22 | 22 Negative | 88 | 88 Negative |
| 1.25 ng/mL | 25% | 22 | 22 Negative | 88 | 88 Negative |
| 2.5 ng/mL | 50% | 22 | 22 Negative | 88 | 88 Negative |
| 3.75 ng/mL | 75% | 22 | 22 Negative | 88 | 88 Negative |
| 5 ng/mL | 100% | 22 | 1 Neg / 21 Pos | 88 | 19 Neg / 69 Pos |
| 6.25 ng/mL | 125% | 22 | 22 Positive | 88 | 88 Positive |
| 7.5 ng/mL | 150% | 22 | 22 Positive | 88 | 88 Positive |
| 8.75 ng/mL | 175% | 22 | 22 Positive | 88 | 88 Positive |
| 10 ng/mL | 200% | 22 | 22 Positive | 88 | 88 Positive |
2. Linearity/Reportable range:
To demonstrate linearity in the semiquantitative mode, which is used for purposes of sample dilution and quality control procedures, a drug-free urine pool spiked with norbuprenorphine 20 ng/mL was serially diluted in increments of 10% and results were obtained. The recovery of norbuprenorphine spiked to various concentrations was evaluated and the average recovery from these 10 replicates was used to determine the functional linearity range of the assay. The average recovery across the linear range of the assay was found to range between 99.6% - 106.3%.
3. Analytical Specificity/Interference:
Various potentially interfering substances were evaluated for positive and negative interference with the assay. Test compounds were spiked into a buprenorphine-free sample, as well as samples containing buprenorphine at 3.75 ng/mL or 6.25 ng/mL, (as negative or positive controls, ±25% of the cutoff concentration, respectively). Samples were then evaluated against the assay's calibration curve in qualitative mode.
Negative interference was observed with Boric Acid at 1% w/v. at ±50% of the cutoff concentration. No other significant cross-reactivity was observed. The potential interferents and the concentrations at which they were tested are shown below:
| Interfering Substance | Concentration of Compound (mg/dL) |
| --- | --- |
| Acetone | 1,000 |
| Ascorbic acid | 500 |
| Bilirubin | 2 |
| Biotin | 2 |
| Boric acid | 1,000 |
| Calcium chloride | 300 |
| Citric acid | 200 |
| Creatinine | 500 |
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| Ethanol | 1,000 |
| --- | --- |
| Galactose | 10 |
| γ-Globulin | 500 |
| Glucose | 3,000 |
| Hemoglobin | 300 |
| Human urine (pooled) | N/A |
| Human serum albumin | 500 |
| β-Hydroxybutyric acid | 100 |
| Oxalic acid | 100 |
| Potassium chloride | 1,000 |
| Riboflavin | 7.5 |
| Sodium azide | 1,000 |
| Sodium chloride | 1,000 |
| Sodium fluoride | 1,000 |
| Sodium phosphate | 300 |
| Urea | 6,000 |
| Uric acid | 10 |
| Urine-based calibrator buffer | N/A |
Cross reactivity of various potentially interfering drugs was evaluated by spiking various concentrations of each substance up to 100,000 ng/mL of buprenorphine metabolites into a pool of drug-free human urine. Results for both 5 and 10 cutoffs are shown below:
## Cross reactivity: 5 cutoff
### Buprenorphine and Major Metabolites:
| Compound | Test Concentration (ng/mL) | Semi-Quantitative Result (ng/mL) | % Cross-reactivity |
| --- | --- | --- | --- |
| Norbuprenorphine | 10 | 10.5 | 100.0% |
| Buprenorphine | 10 | 10.5 | 100.0% |
| Buprenorphine Glucuronide | 105 | 12.0 | 9.5% |
| Norbuprenorphine Glucuronide | 600 | 10.5 | 1.7% |
The sponsor also tested a list of structurally related and un-related Opiate compounds. Results are shown below:
### Structurally related or unrelated Opiate compounds:
| Compound | Test Concentration (ng/mL) | Qualitative Result (mAU) | Semi-Quantitative Result (ng/mL) | % Cross-reactivity |
| --- | --- | --- | --- | --- |
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| Codeine | 100,000 | -17.2 | -0.98 | ND |
| --- | --- | --- | --- | --- |
| Codeine 6β D-Glucuronide | 100,000 | 0.0 | 0.18 | ND |
| Dextromethorphan | 100,000 | 14.3 | 1.43 | ND |
| Dextrorphan Tartrate | 100,000 | -7.3 | -0.15 | ND |
| Dihydrocodeine | 100,000 | 3.5 | 0.51 | ND |
| Dihydromorphine | 100,000 | -7.4 | -0.23 | ND |
| EDDP | 100,000 | -6.0 | -0.08 | ND |
| EMDP | 100,000 | 12.1 | 1.28 | ND |
| Ethylmorphine | 100,000 | -8.0 | -0.15 | ND |
| Fentanyl | 100,000 | -22.4 | -0.66 | ND |
| Heroin | 100,000 | -8.8 | -0.09 | ND |
| Hydrocodone | 100,000 | -18.4 | -0.63 | ND |
| Hydromorphone | 100,000 | -20.8 | -0.81 | ND |
| Hydromorphone 3β D- Glucuronide | 10,000 | -5.0 | -0.02 | ND |
| LAAM | 100,000 | 12.3 | 1.33 | ND |
| Levorphanol | 100,000 | -5.8 | -0.05 | ND |
| Meperidine | 100,000 | 12.6 | 1.38 | ND |
| Meperidine | 100,000 | -15.6 | -0.68 | ND |
| Methadone | 100,000 | -18.7 | -0.73 | ND |
| Morphine | 100,000 | -11.8 | -0.73 | ND |
| Morphine 3β D-Glucuronide | 100,000 | -6.0 | -0.32 | ND |
| Morphine 6 D-Glucuronide | 100,000 | -3.1 | 0.24 | ND |
| N-Desmethyl-cis-Tramadol | 100,000 | -7.5 | -0.10 | ND |
| Nalbuphine | 100,000 | -5.8 | -0.21 | ND |
| Nalorphine | 100,000 | -2.1 | 0.12 | ND |
| Naloxegol | 100,000 | 36.9 | 1.86 | ND |
| Naloxone | 100,000 | 1.0 | -0.20 | ND |
| Naltrexone | 100,000 | 15.2 | 1.26 | ND |
| Norcodeine | 100,000 | -8.9 | -0.35 | ND |
| Norhydrocodone | 100,000 | -7.4 | -0.09 | ND |
| Normorphine | 100,000 | -8.6 | -0.27 | ND |
| Noroxycodone | 100,000 | -4.6 | -0.05 | ND |
| Noroxymorphone | 100,000 | -4.5 | 0.29 | ND |
| Norpropoxyphene | 100,000 | 12.0 | 1.40 | ND |
| O-Desmethyl-cis-Tramadol | 100,000 | -8.5 | -0.36 | ND |
| Oxycodone | 100,000 | -13.5 | -0.57 | ND |
| Oxymorphone | 100,000 | -15.6 | -0.80 | ND |
| Oxymorphone 3β D- Glucuronide | 10,000 | -3.9 | 0.14 | ND |
| Pentazocine | 100,000 | -8.2 | -0.32 | ND |
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Structurally Unrelated Pharmacological Compounds:
| Compound | Test Concentration (ng/mL) | 0 ng/mL Norbuprenorphine | -25% Norbuprenorphine Cutoff (3.75 ng/mL) | +25% Norbuprenorphine Cutoff (6.25 ng/mL) |
| --- | --- | --- | --- | --- |
| | | % Cross | Result | Result |
| Acetaminophen | 100,000 | Neg | Neg | Pos |
| 6-Acetylmorphine | 100,000 | Neg | Neg | Pos |
| Acetylsalicylic Acid | 100,000 | Neg | Neg | Pos |
| Amitriptyline | 100,000 | Neg | Neg | Pos |
| Amlodipine Besylate | 100,000 | Neg | Neg | Pos |
| Amoxicillin | 100,000 | Neg | Neg | Pos |
| d-Amphetamine | 100,000 | Neg | Neg | Pos |
| Atorvastatin | 100,000 | Neg | Neg | Pos |
| Benzoylecgonine | 100,000 | Neg | Neg | Pos |
| Bupropion | 100,000 | Neg | Neg | Pos |
| Caffeine | 100,000 | Neg | Neg | Pos |
| Carbamazepine | 100,000 | Neg | Neg | Pos |
| Cetirizine | 100,000 | Neg | Neg | Pos |
| Chlorpheniramine | 100,000 | Neg | Neg | Pos |
| Chlorpromazine | 100,000 | Neg | Neg | Pos |
| Clomipramine | 100,000 | Neg | Neg | Pos |
| Desipramine | 100,000 | Neg | Neg | Pos |
| Diphenhydramine | 100,000 | Neg | Neg | Pos |
| Duloxetine | 100,000 | Neg | Neg | Pos |
| Fluoxetine | 100,000 | Neg | Neg | Pos |
| Fluphenazine | 100,000 | Neg | Neg | Pos |
| Gabapentin | 100,000 | Neg | Neg | Pos |
| Ibuprofen | 100,000 | Neg | Neg | Pos |
| Imipramine | 100,000 | Neg | Neg | Pos |
| Lisinopril | 100,000 | Neg | Neg | Pos |
| Losartan | 100,000 | Neg | Neg | Pos |
| Loratidine | 100,000 | Neg | Neg | Pos |
| MDA (3,4-methylenedioxyamphetamine) | 100,000 | Neg | Neg | Pos |
| MDEA | 100,000 | Neg | Neg | Pos |
| MDMA (3,4-methylenedioxymethamphetamine) | 100,000 | Neg | Neg | Pos |
| Metformin | 100,000 | Neg | Neg | Pos |
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Structurally related or unrelated Opiate compounds:
| Compound | Test Concentration (ng/mL) | Qualitative Result (mAU) | Semi-Quantitative Result (ng/mL) | % Cross-reactivity |
| --- | --- | --- | --- | --- |
| Codeine | 100,000 | -7.6 | -1.2 | ND |
| Codeine 6β D-Glucuronide | 100,000 | -2.0 | 0.1 | ND |
| Dextromethorphan | 100,000 | 5.6 | 1.4 | ND |
| Dextrorphan Tartrate | 100,000 | -2.9 | -0.7 | ND |
| Dihydrocodeine | 100,000 | 2.0 | 0.6 | ND |
| Dihydromorphine | 100,000 | 0.2 | -0.1 | ND |
| EDDP | 100,000 | -4.2 | -0.4 | ND |
| EMDP | 100,000 | 5.1 | 1.0 | ND |
| Ethylmorphine | 100,000 | -4.9 | -0.4 | ND |
| Fentanyl | 100,000 | -8.9 | -1.7 | ND |
| Heroin | 100,000 | -4.6 | -0.7 | ND |
| Hydrocodone | 100,000 | -5.7 | -1.0 | ND |
| Hydromorphone | 100,000 | -7.6 | -1.3 | ND |
| Hydromorphone 3β D-Glucuronide | 10,000 | -2.2 | -0.2 | ND |
| LAAM | 100,000 | 5.9 | 1.4 | ND |
| Levorphanol | 100,000 | -3.2 | -0.4 | ND |
| Meperidine | 100,000 | 4.6 | 0.9 | ND |
| Meperidine | 100,000 | -16.3 | -1.1 | ND |
| Methadone | 100,000 | -16.4 | -1.3 | ND |
| Morphine | 100,000 | -14.2 | -1.0 | ND |
| Morphine 3β D-Glucuronide | 100,000 | -4.8 | -0.1 | ND |
| Metoprolol | 100,000 | Neg | Neg | Pos |
| --- | --- | --- | --- | --- |
| d-Methamphetamine | 100,000 | Neg | Neg | Pos |
| Nalmefene | 100,000 | Neg | Neg | Pos |
| Nicotine | 100,000 | Neg | Neg | Pos |
| Nortriptyline | 100,000 | Neg | Neg | Pos |
| Omeprazole | 100,000 | Neg | Neg | Pos |
| Oxazepam | 100,000 | Neg | Neg | Pos |
| Phenobarbital | 100,000 | Neg | Neg | Pos |
| (1S,2S)-(+)Pseudoephedrine | 100,000 | Neg | Neg | Pos |
| Quetiapine | 100,000 | Neg | Neg | Pos |
| Ranitidine | 100,000 | Neg | Neg | Pos |
| Salbutamol (Albuterol) | 100,000 | Neg | Neg | Pos |
| Sertraline | 100,000 | Neg | Neg | Pos |
| THC-COOH (11-Nor-Delta-9-THC-9-carboxylic acid) | 100,000 | Neg | Neg | Pos |
| L-Thyroxine | 100,000 | Neg | Neg | Pos |
| Zolpidem | 100,000 | Neg | Neg | Pos |
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Structurally Unrelated Pharmacological Compounds:
| Compound | Test Concentration (ng/mL) | 0 ng/mL Norbuprenorphine | -25% Norbuprenorphine Cutoff (3.75 ng/mL) | +25% Norbuprenorphine Cutoff 6.25 ng/mL) |
| --- | --- | --- | --- | --- |
| | | % Cross | Result | Result |
| Acetaminophen | 100,000 | Neg | Neg | Pos |
| 6-Acetylmorphine | 100,000 | Neg | Neg | Pos |
| Acetylsalicylic Acid | 100,000 | Neg | Neg | Pos |
| Amitriptyline | 100,000 | Neg | Neg | Pos |
| Amlodipine Besylate | 100,000 | Neg | Neg | Pos |
| Amoxicillin | 100,000 | Neg | Neg | Pos |
| d-Amphetamine | 100,000 | Neg | Neg | Pos |
| Atorvastatin | 100,000 | Neg | Neg | Pos |
| Benzoylecgonine | 100,000 | Neg | Neg | Pos |
| Bupropion | 100,000 | Neg | Neg | Pos |
| Caffeine | 100,000 | Neg | Neg | Pos |
| Carbamazepine | 100,000 | Neg | Neg | Pos |
| Cetirizine | 100,000 | Neg | Neg | Pos |
| Chlorpheniramine | 100,000 | Neg | Neg | Pos |
| Chlorpromazine | 100,000 | Neg | Neg | Pos |
| Clomipramine | 100,000 | Neg | Neg | Pos |
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| Desipramine | 100,000 | Neg | Neg | Pos |
| --- | --- | --- | --- | --- |
| Diphenhydramine | 100,000 | Neg | Neg | Pos |
| Duloxetine | 100,000 | Neg | Neg | Pos |
| Fluoxetine | 100,000 | Neg | Neg | Pos |
| Fluphenazine | 100,000 | Neg | Neg | Pos |
| Gabapentin | 100,000 | Neg | Neg | Pos |
| Ibuprofen | 100,000 | Neg | Neg | Pos |
| Imipramine | 100,000 | Neg | Neg | Pos |
| Lisinopril | 100,000 | Neg | Neg | Pos |
| Losartan | 100,000 | Neg | Neg | Pos |
| Loratidine | 100,000 | Neg | Neg | Pos |
| MDA (3,4-methylenedioxyamphetamine) | 100,000 | Neg | Neg | Pos |
| MDEA | 100,000 | Neg | Neg | Pos |
| MDMA (3,4-methylenedioxymethamphetamine) | 100,000 | Neg | Neg | Pos |
| Metformin | 100,000 | Neg | Neg | Pos |
| Metoprolol | 100,000 | Neg | Neg | Pos |
| d-Methamphetamine | 100,000 | Neg | Neg | Pos |
| Nalmefene | 100,000 | Neg | Neg | Pos |
| Nicotine | 100,000 | Neg | Neg | Pos |
| Nortriptyline | 100,000 | Neg | Neg | Pos |
| Omeprazole | 100,000 | Neg | Neg | Pos |
| Oxazepam | 100,000 | Neg | Neg | Pos |
| Phenobarbital | 100,000 | Neg | Neg | Pos |
| (1S,2S)-(+)Pseudoephedrine | 100,000 | Neg | Neg | Pos |
| Quetiapine | 100,000 | Neg | Neg | Pos |
| Ranitidine | 100,000 | Neg | Neg | Pos |
| Salbutamol (Albuterol) | 100,000 | Neg | Neg | Pos |
| Sertraline | 100,000 | Neg | Neg | Pos |
| THC-COOH (11-Nor-Delta-9-THC-9-carboxylic acid) | 100,000 | Neg | Neg | Pos |
| L-Thyroxine | 100,000 | Neg | Neg | Pos |
| Zolpidem | 100,000 | Neg | Neg | Pos |
Among all structurally unrelated pharmacological compounds tested, no cross-reactivity was observed with any compound tested at -25% of the norbuprenorphine cutoff concentration with the 5 ng/mL cutoff.
Samples ranging in specific gravity from 1.000 to 1.030 were split into three portions each and either left un-spiked or further spiked to a final buprenorphine concentration of either 3.75 ng/mL or 6.25 ng/mL. Samples were evaluated in both qualitative and semi-quantitative modes. No interference was observed.
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Negative urine and urine spiked with norbuprenorphine to the final buprenorphine concentration of either 3.75 ng/mL or 6.25 ng/mL were assessed for interference from pH. No interference was observed between pH of 3 to 11.
4. Detection Limit: The lowest concentration that can be differentiated from the negative urine with 95% confidence is determined as 1.0 ng/mL
5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods): Traceable to a commercially available standard.
6. Assay Cut-Off:
See Precision section above.
## B Comparison Studies:
1. Method Comparison with Predicate Device:
A total of ninety-four (94) unaltered clinical samples were tested with the LZI Buprenorphine II Enzyme Immunoassay on the Beckman Coulter AU480 automated clinical analyzer. All samples were tested in singlet. All samples were confirmed with LC/MS for both buprenorphine and norbuprenorphine concentrations.
Results are shown in the tables below.
Semi-Quantitative Accuracy Study:
| BUP II Results
5 ng/mL Cutoff | Negative by LC/MS analysis | < 50% of the cutoff concentration by LC/MS analysis | Near Cutoff Negative between 50% below the cutoff and the cutoff concentration by LC/MS analysis | Near Cutoff Positive between the cutoff and 50% above the cutoff concentration by LCMS analysis | High Positive greater than 50% above the cutoff concentration by LC/MS analysis |
| --- | --- | --- | --- | --- | --- |
| Positive at or above the cutoff by EIA analysis | 0 | 7* | 12* | 14 | 33 |
| Negative below the cutoff by EIA analysis | 20 | 6 | 2 | 0 | 0 |
* These samples were confirmed to contain known cross reactants (buprenorphine glucuronide and norbuprenorphine glucuronide), which significantly contributed to the discrepant results observed.
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2. Matrix Comparison: Not applicable.
C Clinical Studies:
1. Clinical Sensitivity: Not applicable.
2. Clinical Specificity: Not applicable.
3. Clinical Cut-Off: Not applicable
4. Other Clinical Supportive Data (When 1. and 2. Are Not Applicable): Not applicable.
D Expected Values/Reference Range:
Not applicable.
VIII Proposed Labeling:
The labeling supports the finding of substantial equivalence for this device.
IX Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
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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.