Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium

Mahmoud A. ElSohly; Donald F. Stanford; Timothy P. Murphy; Barry M. Lester; Linda L. Wright; Vincent L. Smeriglio; Joel Verter; Charles R. Bauer; Seetha Shankaran; Henrietta S. Bada; H. Chip Walls

doi:10.1093/jat/23.6.436

Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium

Mahmoud A. ElSohly, Donald F. Stanford, Timothy P. Murphy, Barry M. Lester, Linda L. Wright, Vincent L. Smeriglio, Joel Verter, Charles R. Bauer, Seetha Shankaran, Henrietta S. Bada, H. Chip Walls

Research output: Contribution to journal › Article › peer-review

59 Scopus citations

Abstract

The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT(TM) and TDx(TM) immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-Δ⁹-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS(TM) system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-Δ⁹-THC may be major contributors to the immunoassay response in meconium.

Original language	English
Pages (from-to)	436-445
Number of pages	10
Journal	Journal of Analytical Toxicology
Volume	23
Issue number	6
DOIs	https://doi.org/10.1093/jat/23.6.436
State	Published - 1999

Bibliographical note

Funding Information:
This work was supported in part by NICHDM aternal Lifestyle Study, NIH Grant No. 5-U10-HD27904-02, subcontract from Women and Infants Hospital to ElSohly Laboratories, Incorporated (ELI).T he authors acknowledget he efforts provided by members of the NICHD/NIDAS cientificA dvisory Committee throughout the course of the work: Edward J. Cone, Marilyn Huestis, C. LindseyD e Vane, Bruce Goldberger,A mandaJenkins, Michael R. Baylor, Donna Bush, Robert Stephenson, Diana Wilkins, Doug Rollins, and Petrina Babcock.

ASJC Scopus subject areas

Analytical Chemistry
Environmental Chemistry
Toxicology
Health, Toxicology and Mutagenesis
Chemical Health and Safety

Access to Document

10.1093/jat/23.6.436

Cite this

@article{fbf5e03a8d1b455598739976fc578abb,

title = "Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium",

abstract = "The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT(TM) and TDx(TM) immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-Δ9-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS(TM) system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-Δ9-THC may be major contributors to the immunoassay response in meconium.",

author = "ElSohly, {Mahmoud A.} and Stanford, {Donald F.} and Murphy, {Timothy P.} and Lester, {Barry M.} and Wright, {Linda L.} and Smeriglio, {Vincent L.} and Joel Verter and Bauer, {Charles R.} and Seetha Shankaran and Bada, {Henrietta S.} and Walls, {H. Chip}",

note = "Funding Information: This work was supported in part by NICHDM aternal Lifestyle Study, NIH Grant No. 5-U10-HD27904-02, subcontract from Women and Infants Hospital to ElSohly Laboratories, Incorporated (ELI).T he authors acknowledget he efforts provided by members of the NICHD/NIDAS cientificA dvisory Committee throughout the course of the work: Edward J. Cone, Marilyn Huestis, C. LindseyD e Vane, Bruce Goldberger,A mandaJenkins, Michael R. Baylor, Donna Bush, Robert Stephenson, Diana Wilkins, Doug Rollins, and Petrina Babcock.",

year = "1999",

doi = "10.1093/jat/23.6.436",

language = "English",

volume = "23",

pages = "436--445",

number = "6",

}

TY - JOUR

T1 - Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium

AU - ElSohly, Mahmoud A.

AU - Stanford, Donald F.

AU - Murphy, Timothy P.

AU - Lester, Barry M.

AU - Wright, Linda L.

AU - Smeriglio, Vincent L.

AU - Verter, Joel

AU - Bauer, Charles R.

AU - Shankaran, Seetha

AU - Bada, Henrietta S.

AU - Walls, H. Chip

N1 - Funding Information: This work was supported in part by NICHDM aternal Lifestyle Study, NIH Grant No. 5-U10-HD27904-02, subcontract from Women and Infants Hospital to ElSohly Laboratories, Incorporated (ELI).T he authors acknowledget he efforts provided by members of the NICHD/NIDAS cientificA dvisory Committee throughout the course of the work: Edward J. Cone, Marilyn Huestis, C. LindseyD e Vane, Bruce Goldberger,A mandaJenkins, Michael R. Baylor, Donna Bush, Robert Stephenson, Diana Wilkins, Doug Rollins, and Petrina Babcock.

PY - 1999

Y1 - 1999

N2 - The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT(TM) and TDx(TM) immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-Δ9-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS(TM) system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-Δ9-THC may be major contributors to the immunoassay response in meconium.

AB - The analysis of meconium specimens for metabolites of substances of abuse is a relatively accurate method for the detection of fetal exposure to drugs. Most of the methods reported in the literature before the early 1990s relied on radioimmunoassays. The purpose of this study was to develop and validate methods for meconium sample preparation for the screening and gas chromatography-mass spectrometry (GC-MS) confirmation of meconium extracts for cannabinoids, cocaine, opiates, amphetamines, and phencyclidine. EMIT(TM) and TDx(TM) immunoassays were evaluated as screening methods. The sample preparation method developed for screening included extraction and purification prior to analysis. Cutoff levels were administratively set at 20 ng/g for 11-nor-Δ9-THC-9-COOH (THCCOOH) and phencyclidine and at 200 ng/g for benzoylecgonine, morphine, and amphetamines, although lower levels could be detected in meconium using the EMIT-ETS(TM) system. Ninety-five meconium specimens were subjected to the screening procedure with GC-MS confirmation of presumptive positives. In addition, 30 (40 for cocaine) meconium specimens were subjected to GC-MS analysis for all analytes regardless of the screening results to determine the false-negative rate, if any, of the immunoassay. Although there were no false negatives detected, the GC-MS confirmation rate for the immunoassay-positive specimens was generally low, ranging from 0% for amphetamines to 75% for opiates. The lowest rate of confirmed positives was found with the cannabinoids, suggesting that tetrahydrocannabinol (THC) metabolites other than free 11-nor-9-carboxy-Δ9-THC may be major contributors to the immunoassay response in meconium.

UR - http://www.scopus.com/inward/record.url?scp=0032845143&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032845143&partnerID=8YFLogxK

U2 - 10.1093/jat/23.6.436

DO - 10.1093/jat/23.6.436

M3 - Article

C2 - 10517548

AN - SCOPUS:0032845143

SN - 0146-4760

VL - 23

SP - 436

EP - 445

JO - Journal of Analytical Toxicology

JF - Journal of Analytical Toxicology

IS - 6

ER -

Immunoassay and GC-MS procedures for the analysis of drugs of abuse in meconium

Abstract

Bibliographical note

ASJC Scopus subject areas

Access to Document

Other files and links

Fingerprint

Cite this