Screening and confirmation of psilocin, mitragynine, phencyclidine, ketamine and ketamine metabolites by liquid chromatography-tandem mass spectrometry.

A safe and productive workplace requires a sober workforce, free from substances that impair judgment and concentration. Although drug monitoring programs already exist, the scope and loopholes of standard workplace testing panels are well known, allowing other substances to remain a source of risk. Therefore, a high-throughput urine screening method for psilocin, mitragynine, phencyclidine, ketamine, norketamine and dehydronorketamine was developed and validated in conjunction with a urine and blood confirmation method. There are analytical challenges to overcome with psilocin and mitragynine, particularly when it comes to drug stability and unambiguous identification in authentic specimens. Screening and confirmation methods were validated according to the American National Standards Institute/Academy Standards Board (ANSI/ASB) Standard 036, Standard Practices for Method Validation in Forensic Toxicology. An automated liquid handling system equipped with dispersive pipette extraction tips was utilized for preparing screening samples, whereas an offline solid-phase extraction method was used for confirmation sample preparation. Both methods utilized liquid chromatography-tandem mass spectrometry to achieve limits of detection between 1-5 ng/mL for the screening method and 1 ng/mL for the confirmation method. Automation allows for faster throughput and enhanced quality assurance, which improves turnaround time. Compared to previous in-house methods, specimen volumes were substantially decreased for both blood and urine, which is an advantage when volume is limited. This screening technique is well suited for evaluating large numbers of specimens from those employed in safety-sensitive workforce positions. This method can be utilized by workplace drug testing, human performance and postmortem laboratories seeking robust qualitative screening and confirmation methods for analytes that have traditionally been challenging to routinely analyze.

Vibrational Bands of the 2-Butyn-1-yl Radical.

The 2-butyn-1-yl radical is an isomer of C4H5 and is structurally similar to the propargyl radical, which is the simplest resonance-stabilized hydrocarbon radical. The C4H5 radical is likely to be important to astrochemistry and combustion, similar to propargyl, yet little research has been done on its spectroscopic properties. In this work, seven vibrational bands of the 2-butyn-1-yl radical are reported. The radical was formed by pyrolysis of 1-bromo-2-butyne at 800 K and isolated in a low-temperature argon matrix. The experimentally observed frequencies and intensities of the seven vibrational bands were found to be consistent with QCISD predictions from the literature and with new B3LYP calculations in this work.