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The Psychemedics Microplate EIA For Benzodiazepines in Hair is an in vitro diagnostic device for the qualitative detection of benzodiazepines in hair. The assay is intended for use in workplace settings for the qualitative analysis of human head and body hair. The assay uses a cutoff calibrator of 1 ng oxazepam/10 mg hair.

The immunoassay consists of two parts; a pre-analytical hair treatment procedure (to convert the solid matrix of hair to a measurable liquid matrix) and the screening assay, the Psychemedics Microplate EIA for Benzodiazepines. The screening portion of the test system consists of microplate wells coated with Oxazepam conjugated to bovine serum albumin (BSA), the prepared hair sample, a cutoff calibrator added to the sample at a concentration of 1 ng Oxazepam/10 mg hair, monoclonal mouse anti-Oxazepam antibody, goat anti-mouse secondary antibody conjugated to HRP (horseradish peroxidase), substrate [3, 3', 5, 5' tetramethylbenzidine (TMB)], HCl to acidify (and stop the reaction), and wash buffer for washing the plates. Absorbance in the wells is read with a microplate reader.

The confirmation assay consists of a AB Sciex API 3200 LC/MS/MS (Serial numbers AA24661109 and AA28841310) linked to two Shimazu LC-20AD Micro pumps and a Leap Technologies PAL autosampler.

The provided text describes the performance characteristics of the "Psychemedics Microplate EIA for Benzodiazepines in Hair" (the "device") and its supporting studies. The information is presented in the context of a 510(k) premarket notification to the FDA, demonstrating substantial equivalence to a predicate device.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" for each performance metric in a pass/fail format. Instead, it describes validated ranges and outcomes that were considered acceptable for demonstrating the device's performance. The reported performance is directly from the tables and text provided.

• Negative, 25%, 50%, 75% of cutoff: 15/0 (Negative/Positive)
• Cutoff: 7/8 (Negative/Positive)
• 125%, 150%, 175%, 200% of cutoff: 0/15 (Negative/Positive)
  Inter-Assay:
• Negative, 25%, 50%, 75% of cutoff: 75/0 (Negative/Positive)
• Cutoff: 43/32 (Negative/Positive)
• 125%, 150%, 175%, 200% of cutoff: 0/75 (Negative/Positive) |
  | LC-MS/MS Precision | %CV of 10% or less for each level tested; concentrations within ± 15% of target; correlation coefficient >0.995; mean of replicates within ± 15% of predicted. | Alprazolam: %CV range 2.96% - 11.45% (n=5 samples, triplicate reps)
  Lorazepam: %CV range 4.83% - 7.42% (n=4 samples, triplicate reps)
  Diazepam: %CV range 0.91% - 12.77% (n=5 samples, triplicate reps)
  Nordiazepam: %CV range 3.81% - 7.75% (n=4 samples, triplicate reps)
  Oxazepam: %CV range 2.25% - 10.82% (n=4 samples, triplicate reps)
  Temazepam: %CV range 1.99% - 13.12% (n=5 samples, triplicate reps) |
  | LC-MS/MS Linearity | %CV ≤ 10%, concentrations within ± 15% of target, correlation coefficient >0.995, mean of replicates within ± 15% of predicted value based on linear regression. | All conditions met, establishing a linear range of 0.05 to 20.0 ng/10 mg hair for Alprazolam, Lorazepam, Diazepam, Nordiazepam, and Temazepam. |
  | LC-MS/MS Detection Limit (LLOQ) | Analyte response at LLOQ ≥ 5 times blank response; identifiable, discrete, reproducible peak; precision (CV) ≤ 20%; accuracy within 20% of nominal. | LLOQ of 0.05 ng/10 mg hair for all six benzodiazepines, with all acceptance criteria satisfied. |
  | Immunoassay Specificity (Cross-reactivity) | N/A (listed cross-reactivity percentages) | Varies significantly by compound (e.g., Clobazam 550%, Oxazepam 100%, Lorazepam 13%, 7-aminoclonazepam

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