Simultaneous determination of morphine, codeine and 6-acetyl morphine in human urine and blood samples using direct aqueous derivatisation: Validation and application to real cases

Opiates play a relevant role in forensic toxicology and their assay in urine or blood is usually performed for example in workplace drug-testing or toxicological investigation of drug impaired driving. The present work describes two new methods for detecting morphine, codeine and 6-monoacethyl morphine in human urine or blood using a single step derivatisation in aqueous phase. Propyl chloroformate is used as the dramatizing agent followed by liquid-liquid extraction and gas-chromatography-mass spectroscopy to detect the derivatives. The methods have been validated both for hydrolysed and unhydrolysed urine. For hydrolysed urine, the LOB and LOQ were 2.5 ng/ml and 8.5 ng/ml for codeine, and 5.2 ng/ml and 15.1 ng/ml for morphine, respectively. For unhydrolysed urine, the LOD and LOQ were 3.0 ng/ml and 10.1 ng/ml for codeine, 2.7 ng/ml and 8.1 ng/ml for morphine, 0.8 ng/ml and 1.5 ng/ml for 6-monoacetyl morphine, respectively. In blood, the LOB and LOQ were 0.44 ng/ml and 1.46 ng/ml for codeine, 0.29 ng/ml and 0.98 ng/ml for morphine, 0.15 ng/ml and 0.51 ng/ml for 6-monoacetyl morphine, respectively. The validated methods have been applied to 50 urine samples and 40 blood samples (both positive and negative) and they can be used in routine analyses. (C) 2013 Elsevier B.V. All rights reserved.