(214 days)
The Psychemedics homogeneous enzyme immunoassay (HEIA) for phencyclidine in hair is an enzyme immunoassay system for the preliminary qualitative detection of phencyclidine in human head and body hair using a phencyclidine calibrator at 3 ng phencyclidine/10 mg hair for the purpose of identifying phencyclidine use.
This is an in vitro diagnostic device intended exclusively for Psychemedics use only and is not intended for sale to anyone. The Psychemedics phencyclidine homogeneous enzyme immunoassay provides only a preliminary analytical test result. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. Gas Chromatography/Mass Spectrometry (GC/MS), is the preferred confirmatory method.
The test consists of two parts; a pre-analytical hair treatment procedure (to extract phencyclidine from the solid hair matrix to a measurable liquid matrix) and the screening assay, the Psychemedics Phencyclidine Homogeneous Enzyme Immunoassay. The screening portion of the test system is based on competition for antibody binding sites between drug in the measurable liquid matrix and drug-labeled recombinant glucose-6-phosphate dehydrogenase (G6PDH). As the antibody binds labeled G6PDH, enzyme activity decreases. In the presence of drug, enzyme activity increases in direct proportion to the drug concentration. Active enzyme reduces nicotinamide adenine dinucleotide (NAD) to NADH in the presence of glucose-6-phosphate (G6P), resulting in an absorbance change that is measured spectrophotometrically The Psychemedics Phencyclidine HEIA consists of reagents R1 (anti-phencyclidine monoclonal antibody with substrate) and R2 (phencyclidine labeled recombinant G6PDH).
Here's an analysis of the provided text, focusing on the acceptance criteria and the study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state formal "acceptance criteria" with defined numerical targets for sensitivity, specificity, or accuracy. Instead, the performance is described through precision studies and comparison studies using a specific cut-off. For the purpose of this analysis, the reported performance from the comparison study with GC/MS (the preferred confirmatory method) will be presented as the de facto "reported device performance."
| Category | Acceptance Criteria (Implied / Desired) | Reported Device Performance (from Comparison Study with GC/MS) |
|---|---|---|
| Precision | Consistent results at various concentrations relative to the cutoff (3 ng phencyclidine/10 mg hair) | Intra-Assay Precision:- At -100%, -75%, -50%, -25% of cutoff: 8 negative results, 0 positive results.- At +25%, +50%, +75%, +100% of cutoff: 0 negative results, 8 positive results.Inter-Assay Precision:- At -100%, -75%, -50%, -25% of cutoff: 80 negative results, 0 positive results.- At +25%, +50%, +75%, +100% of cutoff: 0 negative results, 80 positive results. |
| Cross-Reactivity | Minimal or no interference from common substances and compounds, except for expected cross-reactants. Expected cross-reactants should have a known equivalent concentration to the 3.0 ng phencyclidine/10 mg hair cutoff. | Cross-Reactive Compounds (≥ 3 ng Phencyclidine/10 mg hair equivalent):- Venlafaxine: 100% cross-reactivity (3 ng equivalent)- Rolicyclidine HCl: 37.5% (8 ng equivalent)- 3-Methoxy-(Aryl Ring) PCP: 30% (10 ng equivalent)- 4-Hydroxy (Cyclohexyl Ring) PCP: 12% (25 ng equivalent)- 1-(1-Phenylcyclohexyl)-4-hydroxypiperidine: 6% (50 ng equivalent)- 1-(1-Phenylcyclohexyl) Morpholine (PCM): 6% (50 ng equivalent)- Metaphit: 4% (75 ng equivalent)- Atropine: 3% (100 ng equivalent)No Cross-Reactivity: A long list of compounds including Anhydroecgonine Methyl Ester, Bupropion, Cotinine, Cannabinol, etc., showed no cross-reactivity. |
| Interference | Minimal or no interference from substances that affect the assay at relevant concentrations. | Interfering Compounds (at 100 ng interferent per 10 mg hair):- Atropine- Chlorpheniramine Maleate- VenlafaxineNo Interference: A long list of compounds including Anhydroecgonine Methyl Ester, Bupropion, Cotinine, Cannabinol, etc., showed no interference. |
| Sample Shipping Stability | Phencyclidine remains detectable and stable in hair samples after storage and shipping. | 7 phencyclidine positive samples remained positive after approximately 8 months in storage and after shipping twice coast-to-coast. |
| Recovery | Extraction method should efficiently recover phencyclidine from hair matrix. | Average recovery was approximately 86% complete after extraction for 3 hours. |
| Cosmetic Treatments | Cosmetic treatments (perm, dye, shampoo, relaxer) should not cause false positives in negative samples, nor false negatives in positive samples. | Negative Samples: 5 phencyclidine-negative head hair samples remained negative after treatment with perm, dye, shampoo, and relaxer.Positive Samples: 10 phencyclidine-positive head hair samples remained positive after treatment with perm, dye, shampoo, and relaxer. |
| Overall Agreement with GC/MS | High concordance between the immunoassay (HEIA) and the confirmatory method (GC/MS) especially for samples around and above the cutoff, recognizing potential discrepancies due to washing procedures for confirmation. | Unwashed GC/MS Comparison:- HEIA Positive / GC/MS < 1.5 ng: 0- HEIA Positive / GC/MS 1.5-2.99 ng: 0- HEIA Positive / GC/MS 3.0-4.5 ng: 4- HEIA Positive / GC/MS > 4.5 ng: 40- HEIA Negative / GC/MS < 1.5 ng: 36- HEIA Negative / GC/MS 1.5-2.99 ng: 4- HEIA Negative / GC/MS 3.0-4.5 ng: 0- HEIA Negative / GC/MS > 4.5 ng: 0Washed GC/MS Comparison:- HEIA Positive / GC/MS < 1.5 ng: 0- HEIA Positive / GC/MS 1.5-2.99 ng: 2- HEIA Positive / GC/MS 3.0-4.5 ng: 7- HEIA Positive / GC/MS > 4.5 ng: 35- HEIA Negative / GC/MS < 1.5 ng: 36- HEIA Negative / GC/MS 1.5-2.99 ng: 4- HEIA Negative / GC/MS 3.0-4.5 ng: 0- HEIA Negative / GC/MS > 4.5 ng: 0Discordant Results (Positive HEIA/Negative GC/MS after washing): Two samples were positive by HEIA but below cutoff (2.47 and 1.73 ng/10 mg hair) after extended washing for GC/MS. This is attributed to the removal of sweat-derived drug and/or environmental contamination by washing, which is not performed prior to screening. |
2. Sample Size Used for the Test Set and Data Provenance
-
Precision Studies:
- Intra-Assay Precision: 8 replicates per concentration level (negative, cutoff, +/- 25%, 50%, 75%, 100% of cutoff).
- Inter-Assay Precision: 80 replicates per concentration level (negative, cutoff, +/- 25%, 50%, 75%, 100% of cutoff).
- Data Provenance: Spiked negative hair with GC/MS validated calibrator and control solutions. The origin of the "negative hair" is not specified but would likely come from in-house or commercial sources. This is a laboratory-controlled study.
-
Cross-Reactivity and Interference Studies:
- The number of samples/tests for each compound is not explicitly stated but implies testing each compound at various concentrations or single key concentrations.
- Data Provenance: Laboratory-controlled studies using the listed compounds.
-
Sample Shipping Stability:
- 7 phencyclidine positive samples.
- Data Provenance: Not explicitly stated, but implies real or spiked positive samples tested after storage and shipping.
-
Cosmetic Treatments:
- 5 phencyclidine-negative head hair samples.
- 10 phencyclidine-positive head hair samples.
- Data Provenance: In-house laboratory study.
-
Comparison Studies (Primary Test Set):
- Total N = 84 individual hair samples.
- 40 negative samples (by predicate device and HEIA).
- 44 positive samples (by predicate device and HEIA).
- Data Provenance: Collected anonymously from a workplace setting. This indicates retrospective real-world samples. The country of origin is not explicitly stated but assumed to be the U.S. given the FDA submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The ground truth for the comparison study was established by Gas Chromatography/Mass Spectrometry (GC/MS). GC/MS is described as the "preferred confirmatory method."
- The document implies that the GC/MS analysis itself establishes the ground truth, rather than human experts interpreting the GC/MS results.
- Therefore, the concept of "number of experts" and their "qualifications" for establishing ground truth in the traditional sense of image or clinical interpretation is not directly applicable here. The GC/MS instrument and its operating/interpreting technicians (who are typically highly qualified analytical chemists or toxicologists) serve to establish the "ground truth" through a validated analytical method.
4. Adjudication Method for the Test Set
- The adjudication method is a direct comparison between the investigational device (Psychemedics HEIA) and the GC/MS confirmatory assay.
- Initially, samples were identified as positive or negative using the predicate device (Psychemedics phencyclidine microplate assay, K111928) and then tested with the HEIA device. The HEIA results were then compared to the GC/MS confirmatory assay.
- For discordant results (e.g., HEIA positive, GC/MS negative after washing), explanations are provided regarding the effect of washing on GC/MS results. This suggests that GC/MS is the ultimate arbiter, even with these nuances. There is no mention of a human consensus or additional adjudicator comparing the HEIA and GC/MS results and making a final decision beyond what the GC/MS represents as the "confirmed analytical result."
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done, If So, What was the Effect Size of How Much Human Readers Improve with AI vs without AI Assistance
- No, an MRMC comparative effectiveness study was not done.
- This device is an in vitro diagnostic immunoassay, not an AI-assisted diagnostic tool that requires human interpretation based on images or complex clinical data. Therefore, the concept of "human readers improve with AI vs without AI assistance" is not relevant to this device.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
- Yes, the primary performance evaluation is a standalone performance study.
- The Psychemedics HEIA for Phencyclidine in Hair is an automated enzyme immunoassay system. Its performance is evaluated directly against the GC/MS confirmatory method without human interpretation as part of the assay itself. The results (positive/negative) are generated directly by the assay and optical reader.
7. The Type of Ground Truth Used
- The primary ground truth used is Gas Chromatography/Mass Spectrometry (GC/MS) confirmation. This is a highly specific and sensitive analytical method for drug detection and quantification, considered the "gold standard" for confirmation in forensic toxicology.
- The document refers to it as the "preferred confirmatory method" and states that "a more specific alternative chemical method must be used in order to obtain a confirmed analytical result" after the preliminary immunoassay.
8. The Sample Size for the Training Set
- The document does not explicitly state a sample size for a "training set."
- Immunoassays are typically developed and optimized through iterative processes based on analytical chemistry principles and validation against known standards, rather than machine learning training sets in the computational sense.
- The calibrators and control materials used for assay setup and validation are prepared from "drug stocks purchased from a commercial vendor," implying a controlled manufacturing and quality assurance process, not a data-driven training set.
9. How the Ground Truth for the Training Set Was Established
- As there is no distinct "training set" in the machine learning sense, the concept of establishing ground truth for it is not applicable.
- However, the underlying data for the calibrators and controls used in assay development and daily operation have their concentrations "confirmed by GC/MS." This ensures the accuracy of the reference materials against which the immunoassay is designed to perform.
{0}------------------------------------------------
Image /page/0/Picture/0 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, with the letters "FDA" in a blue square. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
April 18, 2022
Psychemedics Corporation Neil Stowe Principal Scientist 5832 Uplander Way Culver City, California 90230
Re: K212952
Trade/Device Name: Psychemedics Homogeneous Enzyme Immunoassay (HEIA) for Phencyclidine in Hair Regulatory Class: Unclassified, 510(k) required Product Code: LCM Dated: February 23, 2022 Received: February 24, 2022
Dear Neil Stowe:
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 (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 located 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.
{1}------------------------------------------------
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 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-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 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 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 medical devices and radiation-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.
Marianela Perez-Torres, Ph.D. Deputy Director Division of Chemistry and Toxicology Devices OHT7: Office of In Vitro Diagnostics and Radiological Health Office of Product Evaluation and Quality Center for Devices and Radiological Health
{2}------------------------------------------------
Indications for Use
510(k) Number (if known) K212952
Device Name
Psychemedics Homogeneous Enzyme Immunoassay (HEIA) for Phencyclidine in Hair
Indications for Use (Describe)
The Psychemedics homogeneous enzyme immunoassay (HEIA) for phencyclidine in hair is an enzyme immunoassay system for the preliminary qualitative detection of phencyclidine in human head and body hair using a phencyclidine calibrator at 3 ng phencyclidine/10 mg hair for the purpose of identifying phencyclidine use.
This is an in vitro diagnostic device intended exclusively for Psychemedics use only and is not intended for sale to anyone. The Psychemedics phencyclidine homogeneous enzyme immunoassay provides only a preliminary analytical test result. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. Gas Chromatography/Mass Spectrometry (GC/MS), is the preferred confirmatory method.
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}------------------------------------------------
007 _Phencyclidine Homogeneous Enzyme Immunoassay in Hair 510(k) Summary
This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.
| The assigned 510(k) number is: | K212952 |
|---|---|
| Submitted By: | Psychemedics Corporation |
| 5832 Uplander Way | |
| Culver City, CA 90230 | |
| TEL: 310 216 7776 | |
| FAX: 310 216 6662 | |
| Submission Contact: | Neil Stowe |
| Date Prepared: | 4-12-2022 |
| Device Trade Name: | Psychemedics Homogeneous Enzyme Immunoassay (HEIA) for Phencyclidinein Hair |
| Predicate Device: | Psychemedics Microplate EIA for Phencyclidine in Hair, K111928 |
| Product Code: | LCM (Phencyclidine Test System), |
| Device/Classification Name: | Enzyme Immunoassay Phencyclidine |
| Intended Use: | The Psychemedics homogeneous enzyme immunoassay (HEIA) forphencyclidine in hair is an enzyme immunoassay system for the preliminaryqualitative detection of phencyclidine in human head and body hair using aphencyclidine calibrator at 3 ng phencyclidine/10 mg hair for the purpose ofidentifying phencyclidine use.This is an in vitro diagnostic device intended exclusively for Psychemedics useonly and is not intended for sale to anyone. The Psychemedics phencyclidinehomogeneous enzyme immunoassay provides only a preliminary analytical testresult. A more specific alternative chemical method must be used in order toobtain a confirmed analytical result. Gas Chromatography/Mass Spectrometry(GC/MS) is the preferred confirmatory method. |
| Device Description: | The test consists of two parts; a pre-analytical hair treatment procedure (toextract phencyclidine from the solid hair matrix to a measurable liquid matrix)and the screening assay, the Psychemedics Phencyclidine HomogeneousEnzyme Immunoassay. The screening portion of the test system is based oncompetition for antibody binding sites between drug in the measurable liquidmatrix and drug-labeled recombinant glucose-6-phosphate dehydrogenase(G6PDH). As the antibody binds labeled G6PDH, enzyme activity decreases. Inthe presence of drug, enzyme activity increases in direct proportion to the drugconcentration. Active enzyme reduces nicotinamide adenine dinucleotide (NAD) |
| to NADH in the presence of glucose-6-phosphate (G6P), resulting in anabsorbance change that is measured spectrophotometrically | |
| The Psychemedics Phencyclidine HEIA consists of reagents R1 (anti-phencyclidine monoclonal antibody with substrate) and R2 (phencyclidinelabeled recombinant G6PDH). | |
| Sample Collection and Stability: | A sample of hair should be cut as close as possible to the skin. The hair is placedin a V-shaped aluminum foil sample holder with the root end of the hairprotruding beyond the slanted edge of the foil. The aluminum foil is crimpedaround the sample, securing the hair specimen firmly into place within the foil.The hair sample, crimped within the foil, is placed in a sample acquisition cardenvelope and the envelope is sealed with a tamper-evident seal. Hair specimensare kept at ambient temperature in a secure location until they are shippedwithout refrigeration to the laboratory. Stability of phencyclidine in hair samplesstored at room temperature has been shown for at least 8 months. Phencyclidinein samples shipped coast-to-coast twice was stable. |
| Materials Required: | Hair sample collection kit, Homogeneous Enzyme Immunoassay forPhencyclidine, automated clinical chemistry analyzer, GC/MS for confirmation. |
{4}------------------------------------------------
{5}------------------------------------------------
Comparison with Predicate Devices:
| Item | Proposed Device | Psychemedics Phencyclidine Assay, K111928 |
|---|---|---|
| Indications/Intended Use | The Psychemedics homogeneous enzyme immunoassay (HEIA) for phencyclidine in hair is an enzyme immunoassay system for the preliminary qualitative detection of phencyclidine in human head and body hair using a phencyclidine calibrator of 3 ng phencyclidine/10 mg hair for the purpose of identifying phencyclidine use. This is an in vitro diagnostic device intended exclusively for Psychemedics use only and is not intended for sale to anyone. The Psychemedics Phencyclidine Homogeneous Enzyme Immunoassay provides only a preliminary analytical test result. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. Gas Chromatography/Mass Spectrometry (GC/MS) is the preferred confirmatory method. | The Psychemedics Microplate EIA for Phencyclidine is an enzyme immunoassay (EIA) for the preliminary qualitative detection of phencyclidine in human head and body hair samples using a phencyclidine calibrator at 3 ng/10 mg hair cutoff for the purpose of identifying phencyclidine use. This is an in vitro diagnostic device intended for exclusively for Psychemedics use only and is not for sale to anyone. The Psychemedics EIA phencyclidine Assay provides only a preliminary analytical test result. To obtain a quantitative analytical result or to confirm positive results, a more specific alternate chemical method (e.g. GC/MS) must be used. Clinical consideration and professional judgement should be applied to the interpretation of any drug-of-abuse test result. |
| Product Code | LCM | LCM |
| Measurand | Phencyclidine | Phencyclidine |
| Test System | Psychemedics Homogeneous Enzyme Immunoassay for Phencyclidine in Hair | Psychemedics Microplate EIA for Phencyclidine in Hair |
| Sample Matrix | Human Hair | Human Hair |
| Method of Measurement | Automated Clinical Chemistry Analyzer at 340 nm | Microplate Reader at 450 nm |
| Type of Test | Enzyme Immunoassay | Enzyme Immunoassay |
| Extraction Method | Acidic aqueous buffer | Patented Digestion Method |
| Confirmation Method | GC/MS | GC/MS |
Performance Testing Summary: Precision studies were performed by spiking negative hair with previously GC/MS validated calibrator and control solutions to achieve concentrations of negative, the cutoff calibrator of 3 ng phencyclidine/10 mg hair and +/- 75%, +/-50% and +/-25% of the cutoff calibrator.
{6}------------------------------------------------
| Phencyclidine Intra-Assay and Inter-Assay Precision Summary, 3 ng | ||||||
|---|---|---|---|---|---|---|
| Phencyclidine/10 mg Hair Calibrator | ||||||
| Summary Intra-Assay Precision | Summary Inter-Assay Precision | |||||
| Level | NEG | POS | Level | NEG | POS | |
| -100% | 8 | 0 | -100% | 80 | 0 | |
| -75% | 8 | 0 | -75% | 80 | 0 | |
| -50% | 8 | 0 | -50% | 80 | 0 | |
| -25% | 8 | 0 | -25% | 80 | 0 | |
| +25% | 0 | 8 | +25% | 0 | 80 | |
| +50 | 0 | 8 | +50 | 0 | 80 | |
| +75% | 0 | 8 | +75% | 0 | 80 | |
| +100% | 0 | 8 | +100% | 0 | 80 |
Cross Reactivity Summary: The cross reactivity of the following metabolites and phencyclidine structural analogs was evaluated by determining the minimum concentration that would result approximately equivalent to the 3.0 ng phencyclidine/10 mg hair cutoff.
| Compound | % CrossReactivity | Concentration Equivalent to 3.0 ngPhencyclidine/10 mg Hair |
|---|---|---|
| Venlafaxine | 100 | 3 |
| Rolicyclidine HCl | 37.5 | 8 |
| 3-Methoxy-(Aryl Ring) PCP | 30 | 10 |
| 4-Hydroxy (Cyclohexyl Ring) PCP | 12 | 25 |
| 1-(1-Phenylcyclohexyl)-4-hydroxypiperidine | 6 | 50 |
| 1-(1-Phenylcyclohexyl) Morpholine(PCM) | 6 | 50 |
| Metaphit | 4 | 75 |
| Atropine | 3 | 100 |
The following compounds were shown to have no cross reactivity in the phencyclidine assay using the 3 ng phencyclidine/10 mg hair calibrator.
Anhydroecgonine Methyl Ester, Bupropion, Cotinine, Cannabinol, Chlorpheniramine Maleate, O-Desmethylvenlafaxine, Desipramine, Doxylamine Succinate, 1S, 2R-(+)-Ephedrine, Naproxen, Nicotine, Nortriptyline, H-Propoxyphen, R, R-(-)-Pseudoephedrine, Thioridazine, cis-Tramadol, (±)-11nor-9-Carboxy-Δ9-THC, Pentazocine, Amoxicillin, Propranolol, Promethazine, Phenmetrazine, Phendimetrazine, Benzocaine, Ecgonine, Dextromethorphan, Amitriptyline, R-(-)-Phenylephrine, Glutethimide, Meprobamate, Lidocaine, Carbamazepine, Diazepam, Nordiazepam, AM-2201, JWH-019, JWH-081, JHW-122, Acetaminophen, Caffeine, Dyphylline, Methaqualone, Theophylline, CP47.497, CP47.497 C8 Homologue, HU-211, JWH-200, JWH-250, Ibuprofen, Naproxen, Ethosuximide, (±)-Epinephrine, Norepinephrine, Barbital, Metanephrine, Normetanephrine, Methocarbamol, Alprazolam, Cimoticline, Citalopram, Clopidogrel Bisulfate, Fluconazole, Hydrochloro-thiazide, Lamotrigine, L-Thyroxine, Methyl Phendiate, Omeprazole, Amlodipine Besylate, Atorvastatin, Azithromycin, Bupivacaine, Cetirizine, Dimenhydrinate,
{7}------------------------------------------------
| Lisinopril, Methsuximide, Phensuximide, N-Normethyl Suximide, Butabarbital,Amobarbital, Secobarbital, Hexobarbital, Phenobarbital, Mephyton, Ethotoin,Mephobarbital, PEMA, 10,11-Dihydro-carbamazepine, Medazepam,Chlorpramazine, Flurazepam, Lorazepam, Temazepam, Bromazepam,Primidone, 5,5-Diphenyl Hydantoin, Triamterene, Nordoxepin, Oxazepam,Levitriacetam, Metformin, Phenytoin, R-Phenyl-ephrine, Sertraline, Topiramate,Zolpidem Tartrate, Vanilmandelic Acid, 5-Hydroxy Indole-3-Acetic Acid,Homovanilic Acid | |
|---|---|
| Interference: | The compounds atropine, chlorpheniramine maleate and venlafaxine wereinterferences in the immunoassay when tested at 100 ng interferent per 10 mghair. |
| The following compounds were shown to have no interference in thephencyclidine assay. | |
| Anhydroecgonine Methyl Ester, Bupropion, Cotinine, Cannabinol, O-Desmethylvenlafaxine, Desipramine, Doxylamine Succinate, 1S, 2R-(+)-Ephedrine, Naproxen, Nicotine, Nortriptyline, H-Propoxyphen, R, R-(-)-Pseudoephedrine, Thioridazine, cis-Tramadol, (±)-11-nor-9-Carboxy-Δ9-THC,Pentazocine, Amoxicillin, Propranolol, Promethazine, Phenmetrazine,Phendimetrazine, Benzocaine, Ecgonine, Dextromethorphan, Amitriptyline, R-(-)-Phenylephrine, Glutethimide, Meprobamate, Lidocaine, Carbamazepine,Diazepam, Nordiazepam, AM-2201, JWH-019, JWH-081, JHW-122,Acetaminophen, Caffeine, Dyphylline, Methaqualone, Theophylline, CP47.497,CP47.497 C8 Homologue, HU-211, JWH-200, JWH-250, Ibuprofen, Naproxen,Ethosuximide, (±)-Epinephrine, Norepinephrine, Barbital, Metanephrine,Normetanephrine, Methocarbamol, Alprazolam, Cimoticline, Citalopram,Clopidogrel Bisulfate, Fluconazole, Hydrochloro-thiazide, Lamotrigine, L-Thyroxine, Methyl Phendiate, Omeprazole, Amlodipine Besylate, Atorvastatin,Azithromycin, Bupivacaine, Cetirizine, Dimenhydrinate, Lisinopril,Methsuximide, Phensuximide, N-Normethyl Suximide, Butabarbital,Amobarbital, Secobarbital, Hexobarbital, Phenobarbital, Mephyton, Ethotoin,Mephobarbital, PEMA, 10,11-Dihydro-carbamazepine, Medazepam,Chlorpramazine, Flurazepam, Lorazepam, Temazepam, Bromazepam,Primidone, 5,5-Diphenyl Hydantoin, Triamterene, Nordoxepin, Oxazepam,Levitriacetam, Metformin, Phenytoin, R-Phenyl-ephrine, Sertraline, Topiramate,Zolpidem Tartrate, Vanilmandelic Acid, 5-Hydroxy Indole-3-Acetic Acid,Homovanilic Acid | |
| Calibrator: | Psychemedics prepares calibrators and control materials using drug stockspurchased from a commercial vendor. Each lot of drug is received with itsspecific certificate of analysis. The commercially obtained stock is made intocalibrators and controls to the desired concentrations. The concentrations areconfirmed by GC/MS. |
{8}------------------------------------------------
| Sample Shipping Stability During Storage: | 7 phencyclidine positive samples remained positive after approximately 8 months in storage and after shipping twice coast-to-coast. | ||
|---|---|---|---|
| Recovery: | The hair sample preparation for the screening HEIA is a phosphate buffer extraction procedure. Recovery of phencyclidine in the method was shown on average to be approximately 86% complete after extraction for 3 hours. | ||
| Cosmetic Treatments: | 5 phencyclidine-negative head hair samples were treated with perm, dye, shampoo and relaxer and the results compared to the same samples without treatments. In each case of the 5 samples treated with a type of cosmetic treatment, all samples remained negative after the treatments. | ||
| 10 phencyclidine-positive head hair samples were treated with perm, dye, shampoo and relaxer and the results compared to the same samples without the treatments. In each case, the samples remained positive after the treatments. | |||
| Comparison Studies: | Phencyclidine, 3 ng phencyclidine/10 mg hair calibrator | ||
| Samples positive or negative for phencyclidine were identified using the Psychemedics phencyclidine microplate assay (K111928), and then tested with the test device, the Psychemedics HEIA for phencyclidine in hair. The test device (assay) has been validated at the 3 ng phencyclidine/10 mg hair cutoff using 84 individual hair samples collected anonymously from a workplace setting. 40 negative samples and 44 positive samples were identified by the test device. | |||
| The stored hair samples were then tested using Psychemedics' GC/MS confirmatory assay, to compare the Psychemedics HEIA results with the GC/MS results. The studies comparing the HEIA with GC/MS documented the source of hair (head or body) and other demographics as available. The comparison of the Psychemedics Phencyclidine HEIA at the 3 ng/10 mg hair calibrator with GC/MS is shown in the following table. |
{9}------------------------------------------------
| Phencyclidine 3 ng/10 mg hair Calibrator Comparison Study | ||||
|---|---|---|---|---|
| HEIA Result | Unwashed GC/MS Result, ng Phencyclidine/10 mg hair (% of cutoff calibrator) | |||
| < 1.5 (< 50% below cutoff) | 1.50 – 2.99 (≥ 50% below cutoff to cutoff) | 3.0 – 4.50 (cutoff to ≥ 50% above cutoff) | > 4.50 (> 50% above cutoff) | |
| Positive | 0 | 0 | 4 | 40 |
| Negative | 36 | 4 | 0 | 0 |
| HEIA Result | Phencyclidine 3 ng/10 mg hair Calibrator Comparison StudyWashed GC/MS Result, ng Phencyclidine/10 mg hair (% of cutoff calibrator) | |||
|---|---|---|---|---|
| < 1.5 (< 50% below cutoff) | 1.50 – 2.99 (≥ 50% below cutoff to cutoff) | 3.0 – 4.50 (cutoff to ≥ 50% above cutoff) | > 4.50 (> 50% above cutoff) | |
| Positive | 0 | 2 | 7 | 35 |
| Negative | 36 | 4 | 0 | 0 |
Phencyclidine Discordant Results at the 3 ng phencyclidine/10 mg hair calibrator: Positive HEIA/Negative GC/MS
Washing of hair before confirmation: exclusion of potential environmental contamination and/or sweat-derived drug from hair analysis results can result in APPARENT discordant results. Ingested drugs are present in perspiration, which settles on the hair and requires removal if the hair analysis result is to reflect amount of drug ingested rather than exposure to the sweat-derived drug. Drug could also be present as a result of environmental contamination (e.g., powder, smoke). Hair is not washed prior to screening, as it would not be reasonable to wash hundreds of negative hair samples; i.e., samples that are negative without washing. Thus, it is expected that the washing performed before GC/MS confirmation of presumptive positives removes external drug and the confirmation results may then be lower than the screening may have predicted without the consideration of sweat-derived drug and/or drug from environmental contamination.
| Sample | HEIA Result | Unwashed GC/MSResult (ngPhencyclidine/10 mghair) | Washed GC/MSResult (ngPhencyclidine/10 mghair) | Comment |
|---|---|---|---|---|
| 1 | POS | 4.85 | 1.73 | Sample 1 confirmed ≥ 3.0 ngphencyclidine/10 mg unwashed, <3.0 ng phencyclidine/10 mg afterextended washing. |
| 2 | POS | 3.65 | 2.47 | Sample 2 confirmed ≥ 3.0 ngphencyclidine/10 mg unwashed, <3.0 ng phencyclidine/10 mg afterextended washing. |
Conclusion:
The Psychemedics homogeneous enzyme immunoassay for phencyclidine in hair is substantially equivalent based on acceptable performance studies, including precision, specificity and interference (including cosmetic effects).
N/A