scholarly journals Urine drug testing for opioids, cocaine, and metabolites by direct injection liquid chromatography/tandem mass spectrometry

2003 ◽  
Vol 17 (14) ◽  
pp. 1665-1670 ◽  
Author(s):  
Riet Dams ◽  
Constance M. Murphy ◽  
Willy E. Lambert ◽  
Marilyn A. Huestis
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Drug Testing ◽  
Direct Injection ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Urine Drug Testing ◽  
Urine Drug ◽  
Liquid Chromatography Tandem Mass

scholarly journals Comparative Evaluation of the Accuracy of Benzodiazepine Testing in Chronic Pain Patients Utilizing Immunoassay with Liquid Chromatography Tandem Mass Spectrometry (LC/ MS/MS) of Urine Drug Testing

2011 ◽  
Vol 3;14 (3;5) ◽  
pp. 259-270
Author(s):  
Laxmaiah Manchikanti
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Drug Testing ◽  
Tandem Mass ◽  
Index Test ◽  
Chromatography Tandem Mass Spectrometry ◽  
Urine Drug Testing ◽  
Urine Drug ◽  
Liquid Chromatography Tandem Mass

Background: Eradicating or appreciably limiting controlled prescription drug abuse, such as opioids and benzodiazepines, continues to be a challenge for clinicians, while providing needed, proper treatment. Detection of misuse and abuse is facilitated with urine drug testing (UDT). However, there are those who dispute UDT’s diagnostic accuracy when done in the office (immunoassay) and claim that laboratory confirmation using liquid chromatography tandem mass spectrometry (LC/MS/MS) is required in each and every examination. Study Design: A diagnostic accuracy study of UDT. Study Setting: The study was conducted in a tertiary referral center and interventional pain management practice in the United States. Objective: Comparing UDT results of in-office immunoassay testing (the index test) with LC/MS/ MS (the reference test). Methods: A total of 1,000 consecutive patients were recruited to be participants. Along with demographic information, a urine sample was obtained from them. A nurse conducted the immunoassay testing at the interventional pain management practice location; a laboratory conducted the LC/MS/ MS. All index test results were compared with the reference test results. The index test’s efficiency (agreement) was calculated as were calculations for sensitivity, specificity, false-positive, and false-negative rates. Results: Approximately 36% of the specimens required confirmation. The index test’s efficiency for prescribed benzodiazepines was 78.4%. Reference testing improved accuracy to 83.2%, a 19.6% increase, and 8.9% of participants were found to be taking non-prescribed benzodiazepines. The index test’s false-positive rate for benzodiazepines use was 10.5% in patients receiving benzodiazepines. Limitations: This study was limited by its single-site location, its use of a single type of point of care (POC) kit, and reference testing being conducted by a single laboratory, as well as technical sponsorship. Conclusion: Clinicians should feel comfortable conducting in-office UDT immunoassay testing. The present study shows that it is reliable, expedient, and fiscally sound for all involved. In-office immunoassay testing compares favorably with laboratory testing for benzodiazepines, offering both high specificity and agreement. However, clinicians should be vigilant and wary when interpreting results, weighing all factors involved in their decision. Key words: Controlled substances, benzodiazepines, opioids, illicit drugs, abuse, liquid chromatography tandem mass spectrometry, immunoassay, urine drug testing

scholarly journals Quantitative Determination and Environmental Risk Assessment of 102 Chemicals of Emerging Concern in Wastewater-Impacted Rivers Using Rapid Direct-Injection Liquid Chromatography—Tandem Mass Spectrometry

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5431
Author(s):  
Melanie Egli ◽  
Alicia Hartmann ◽  
Helena Rapp Wright ◽  
Keng Tiong Ng ◽  
Frédéric B. Piel ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Risk Assessment ◽  
Liquid Chromatography ◽  
Tandem Mass Spectrometry ◽  
Quantitative Determination ◽  
Environmental Risk Assessment ◽  
Direct Injection ◽  
Tandem Mass ◽  
Chromatography Tandem Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

The rapid source identification and environmental risk assessment (ERA) of hundreds of chemicals of emerging concern (CECs) in river water represent a significant analytical challenge. Herein, a potential solution involving a rapid direct-injection liquid chromatography–tandem mass spectrometry method for the quantitative determination of 102 CECs (151 qualitatively) in river water is presented and applied across six rivers in Germany and Switzerland at high spatial resolution. The method required an injection volume of only 10 µL of filtered sample, with a runtime of 5.5 min including re-equilibration with >10 datapoints per peak per transition (mostly 2 per compound), and 36 stable isotope-labelled standards. Performance was excellent from the low ng/L to µg/L concentration level, with 260 injections possible in any 24 h period. The method was applied in three separate campaigns focusing on the ERA of rivers impacted by wastewater effluent discharges (1 urban area in the Basel city region with 4 rivers, as well as 1 semi-rural and 1 rural area, each focusing on 1 river). Between 25 and 40 compounds were quantified directly in each campaign, and in all cases small tributary rivers showed higher CEC concentrations (e.g., up to ~4000 ng/L in total in the R. Schwarzach, Bavaria, Germany). The source of selected CECs could also be identified and differentiated from other sources at pre- and post- wastewater treatment plant effluent discharge points, as well as the effect of dilution downstream, which occurred over very short distances in all cases. Lastly, ERA for 41 CECs was performed at specific impacted sites, with risk quotients (RQs) at 1 or more sites estimated as high risk (RQ > 10) for 1 pharmaceutical (diclofenac), medium risk (RQ of 1–10) for 3 CECs (carbamazepine, venlafaxine, and sulfamethoxazole), and low risk (RQ = 0.1–1.0) for 7 CECs (i.e., RQ > 0.1 for 11 CECs in total). The application of high-throughput methods like this could enable a better understanding of the risks of CECs, especially in low flow/volume tributary rivers at scale and with high resolution.

Sign in / Sign up

Export Citation Format

Share Document