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The Psychemedics homogeneous enzyme immunoassay for cocaine in hair is an enzyme immunoassay for the preliminary qualitative detection of cocaine in human head and body hair using a cocaine calibrator of 5 ng/10 mg hair for the purpose of identifying cocaine use. This product is intended exclusively for in-house professional use and not for sale to anyone.

The Psychemedics EIA Cocaine Assay provides only a preliminary analytical test results, a more specific alternate chemical method (e.g. LC/MS/MS) must be used. Clinical consideration and professional judgement should be applied to the interpretation of any drug-of-abuse test result.

Device Description

The homogeneous enzyme immunoassay (HEIA) test consists of two parts; a pre-analytical hair treatment procedure (to extract cocaine from the solid hair matrix to a measurable liquid matrix) and the screening assay, the Psychemedics Cocaine HEIA. 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 Cocaine HEIA consists of reagents R1 (anti-cocaine monoclonal antibody with substrate) and R2 (cocaine labeled recombinant G6PDH).

AI/ML Overview

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Device Name: Psychemedics Homogeneous Enzyme Immunoassay for Cocaine in Hair

Indications for Use: Preliminary qualitative detection of cocaine in human head and body hair using a cocaine calibrator of 5 ng/10 mg hair, for identifying cocaine use. Intended for in-house professional use only. Positive results require confirmation with a more specific alternate chemical method (e.g., LC/MS/MS).

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" with specific pass/fail metrics in a table format. Instead, it details various performance studies and their results to demonstrate substantial equivalence to a predicate device. I've extracted the relevant performance metrics and will organize them as an "acceptance criteria" table for clarity, inferring the implied acceptance for each from the reported results ("all good", "no cross-reactivity", "remained positive/negative").

Acceptance Criteria Category	Implicit Acceptance Criteria / Goal	Reported Device Performance
Precision (Intra-Assay)	Consistent classification (NEG/POS) at various concentrations around cutoff.	At -100%, -75%, -50%, -25% of cutoff, all 8 replicates were NEG. At +25%, +50%, +75%, +100% of cutoff, all 8 replicates were POS.
Precision (Inter-Assay)	Consistent classification (NEG/POS) at various concentrations around cutoff across multiple assays.	At -100%, -75%, -50%, -25% of cutoff, all 80 replicates were NEG. At +25%, +50%, +75%, +100% of cutoff, all 80 replicates were POS.
Cross-Reactivity (Related Compounds)	Low cross-reactivity for structurally related compounds and metabolites to minimize false positives.	Benzoylecgonine: 2.0% cross-reactivity (250 ng/10 mg hair equivalent).
Norcocaine: 20% cross-reactivity (25 ng/10 mg hair equivalent).
Cocaethylene: 55.5% cross-reactivity (9 ng/10 mg hair equivalent).
Ecgonine, Ecgonine Methyl Ester, Anhydroecgonine Methyl Ester: 500 ng/10 mg hair equivalent). (This indicates that significantly higher concentrations of these substances are required to elicit a positive result compared to cocaine, which is generally considered acceptable for preliminary screening).
Interference (Other Compounds)	No interference from common medications or other substances.	Listed a wide array of compounds (e.g., Lisinopril Dihydrate, Atropine, Bupropion, Cannabinol, common prescription drugs, other drug-of-abuse metabolites) that showed no cross-reactivity and no interference in the cocaine assay. (This implies that the assay is specific enough not to react with many other substances).
Sample Shipping Stability	Cocaine detection should remain stable after storage and shipping.	Five cocaine positive samples remained positive after approximately 6 months in storage and after shipping twice coast-to-coast. (Acceptable stability shown).
Recovery	Adequate recovery of cocaine during the hair extraction process.	Recovery of cocaine in the method shown on average to be at least 81% complete after 2 hours. (Acceptable recovery).
Cosmetic Treatments Effect	Cosmetic treatments should not alter detection accuracy for positive or negative samples.	Negative Samples: 10 cocaine-negative head hair samples treated with perm, dye, shampoo, and relaxer remained negative.
Positive Samples: 7 cocaine-positive head hair samples treated with perm, dye, shampoo, and relaxer remained positive. (Acceptable, as cosmetic treatments did not affect results).
Clinical Performance (Study 1)	High concordance with LC/MS/MS with expected discordance attributable to washing for confirmation.	Total Samples Tested: 215 (123 negative, 92 positive by immunoassay).
HEIA Positive / LC/MS/MS > 5 ng/10mg: 89 samples.
HEIA Negative / LC/MS/MS 5 ng/10mg: 39 samples.
HEIA Negative / Unwashed LC/MS/MS 5 ng/10mg: 39 samples.
**HEIA Negative / Washed LC/MS/MS

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