Simultaneous analysis of ten drugs of abuse in blood and urine matrix by gas chromatography–mass spectrometry: Implications for air crash investigation

Introduction: Many of abuse drugs can alter a person’s thinking and judgment, leading to health risks, including addiction, drugged driving and infectious disease. Use of illicit drugs by aviation employees is associated with a significantly increased risk of accidents. The detection and quantitation of drugs of abuse in blood is of growing interest in forensic and clinical toxicology. Generally, the screening for drugs of abuse is carried out by using commercially available immunoassay based urine cassettes; however, such results needs to be confirmed by advanced analytical tools like HPLC, GCMS and LCMS. There have been several attempts to develop confirmatory methods for drugs of abuse in blood and urine. Material and Methods: In the present study in our laboratory, a single method was attempted for simultaneous detection and quantification of 10 drugs of abuse in whole blood and urine matrix by GC-MS Selective Ion Monitoring (SIM) method. Results: Chromatographic separation was optimized and achieved for separation of all 10 compounds using Agilent DB-5MS column. Retention time (Rt), selectivity and sensitivity were achieved by measuring each analyte in Selective Ion Monitoring (SIM) mode. A simple sample preparation method was standardized for extraction of all 10 compounds from blood and urine. Conclusion: The developed method in the study permits identification of these analytes from same biological specimen in small quantities and the method is tested on blood and urine matrix spiked with known concentration of pure compounds.

Simultaneous analysis of eight benzodiazepines in blood and urine matrix by gas chromatography–mass spectrometry: Implications for air crash investigation

Introduction: Benzodiazepines are the most commonly prescribed class of drugs in India and are capable of impairing the performance of an aviator in therapeutic to subtherapeutic levels. Detection of benzodiazepines, particularly in blood, is not easy, since the concentrations present, especially following prescribed medical use, can be very low. Several publications have addressed estimation of benzodiazepines in plasma or serum; however, few have attempted their detection in whole blood. Urine, although a better specimen, benzodiazepines due to their extensive metabolism, its metabolites are excreted in urine instead of the parent compounds. Materials and Methods: In our laboratory, a method was developed for simultaneous detection and quantification of eight benzodiazepines in whole blood and urine matrix by gas chromatography–mass spectrometry selective ion monitoring (SIM) method. Chromatographic separation was optimized and achieved for separation of all 8 compounds using Agilent DB-5MS column. Retention time, selectivity and sensitivity were achieved by measuring each analyte in SIM mode. The developed method was tested and validated on actual biological samples for lorazepam, temazepam, diazepam, clonazepam, and nitrazepam. Conclusion: A single method was developed for the detection and quantification of eight benzodiazepines in whole blood and urine matrix by GC–MS SIM method. The method was also tested on limited number of actual biological samples for the lorazepam, temazepam, diazepam, clonazepam, and nitrazepam.

Development and application of a urine drug concentration method for the evaluation of oral absorption of ibandronate in clinical patients

Aim: A urine drug concentration method was developed for the evaluation of oral ibandronte absorption based on the fact that ibandronate is excreted unchanged by the kidneys. Methodology: Ibandronate was isolated from the urine matrix by coprecipitated with 2.5 M CaCl2 and 1 M K2HPO4 in basic conditions. After a liquid–liquid extraction, the analytes were derivatized with trimethylsilydiazomethane prior to detection. Results: The calibration curves exhibited excellent linearity (r > 0.99) between 1 and 250 ng/ml in human urine. Ibandronate was recovered >86.5% with the inter- and intraday relative standard deviations less than 15%. Conclusion: The method is selective, accurate, practical and was successfully applied to study the influence of vitamin D3 on the absorption of ibandronate.

Coupling of capillary-channeled polymer (C-CP) fibers for reversed phase liquid chromatography and ESI-MS for the determination of proteins in a urine matrix

Electrospray ionization mass spectrometry (ESI-MS) analysis provides a great deal of analytical information as a detection mode when coupled with liquid chromatography (LC) and capillary electrophoresis (CE) separations of proteins.