Study: Screening of Opiates in Hair Using a Homogeneous Immunoassay Procedure

A. Agrawal,, M. Vincent, G. Wang, M. Nguyen, C. Castro, C.R. Henry, C. Moore
Immunalysis Corporation, 829 Towne Center Drive, Pomona, CA 91767

Introduction

Hair is a useful specimen for the detection of long-term drug use. In general, drug concentrations in hair are lower than those identified in other matrices (e.g. urine, blood). Specimen volume may be limited, so sensitive screening methods are necessary. Following heroin use, the metabolites detected in hair are 6-AM, morphine and possibly codeine, so a screening immunoassay should be targeted to these analytes.

Methods

● Hair from opiates users (n = 19; 10mg); drug free hair (n = 20; 10mg)
● Cut into small pieces; 0.025 M phosphate buffer added (pH 2.7; 0.5 mL); Incubated (3hrs/75℃)
● Supernatant was analyzed using ELISA; and via homogeneous immunoassays (HEIA) on an Olympus 400 platform
● For ELISA, supernatant was diluted 1:5 with 0.1 M PBS before plating; For HEIA, 20mL of supernatant was used

Cross-reactivity

Results

A screening cutoff of 200 pg/mg of MOR was used, (recommendation Proposed Federal Guidelines 2004)
Precision at 100, 200, 400, 2000 and 5000 pg/mg: 10.7%, 7%, 8.6%, 5.8% and 10.1%
All negative specimens screened negatively using both ELISA and EIA; results of positive specimens shown

Summary

The assay is precise, sensitive and conducive to rapid hair screening using commercial chemistry analyzers

Disclosure

Immunalysis Corporation manufactures and distributes the immunoassays described in this presentation

SOFT 2008

To view the full study and its data, visit this link.

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