A high-throughput multicomponent screening method for diuretics, masking agents, central nervous system (CNS) stimulants and opiates in human urine by UPLC-MS/MS

Quantitative LC-MS/MS Analysis of Opiates and Opioids in Human Urine

We hereby present a direct, clinical LC-MS/MS assay for the simultaneous analysis of opiates and opioids in human urine. The assay is used as confirmations as well as a quantitative assay following immunoassay urine drug screens. Hence, the utility is extended to report opiate/opioid levels in the range 10-1000 ng/mL for each of the 13 analytes, which include morphine and metabolites; codeine and metabolites; as well as synthetics such as heroin metabolites, dihydrocodeine, oxycodone, and naloxone. The assay employs dilute and shoot, utilizing reversed-phase liquid chromatography for mixture separation and positive-mode electrospray-ionization multiple-reaction-monitoring for MS detection in the TSQ Endura triple-quadrupole (QqQ) instrument. Thereafter, quantitative analysis is based on the linear calibration using six reference standards, whereby the instrument response for each analyte at a given concentration is normalized against stable isotope labeled internal standard.

Quantification of sedative-hypnotics in human urine and plasma via polystyrene-based solid phase extraction-LC-MS/MS analysis

Owing to the adverse effects of the overuse of common sedative-hypnotics on human health, the development of an efficient analytical method for the detection of drugs in clinical emergencies and forensic science is significant. Although conventional analytical methods, such as immunoassay, liquid chromatography (LC), gas chromatography, and mass spectrometry (MS) are reliable, they exhibit drawbacks such low-throughput screening and high costs. Thus, in this study, we developed a novel high-throughput method consisting of a polystyrene-based solid phase extraction (SPE) and an LC with tandem MS analysis for the detection of drugs in biological samples and investigated its precision and reliability via the detection of twelve sedative-hypnotics in human urine and plasma samples. Good linear relationship (r ≥ 0.99) were achieved within the concentration range of 0.1-20 ng/mL for the 12 analytes in urine samples. Whereas, in the plasma samples, the correlation coefficient was greater than 0.99 in the concentration range 1-100 ng/mL for lorazepam and clonazepam and in the range 0.5-100 ng/mL for the remaining analytes. The intra- and inter-day precision, autosampler and freeze-thaw stabilities, and lower limit of quantitation (LLOQ) for all twelve analytes in the urine and plasma samples were favorable. Furthermore, sedative-hypnotics were detected in clinical samples obtained from the Hebei General Hospital using this method. These results indicated that the analytical method proposed in this study can be effectively applied in toxicology screening and drug abuse monitoring.The method developed in this study could be applied in clinical and forensic toxicology laboratories for sedative-hypnotic drug screening, providing support for drug abuse monitoring and clinical diagnosis.

Online Turbulent Flow Extraction and Column Switching for the Confirmatory Analysis of Stimulants in Urine by Liquid Chromatography-Mass Spectrometry

Stimulants are often used to treat attention deficit disorders and nasal congestion. As they can be misused and overdosed, the detection of stimulants is relevant in the toxicological field as well as in the doping control field. The effects of stimulants can indeed be beneficial for athletes. Therefore, their in-competition use is prohibited by the World Anti-Doping Agency (WADA). As stimulants represent one of the most detected categories of prohibited substances, automation of methods to detect and confirm their presence is desirable. Previous work has shown the advantages of using turbulent flow online solid-phase extraction liquid chromatography-tandem mass spectrometry (online SPE LC-MS-MS) for the detection and confirmation of diuretics and masking agents. Hence, a turbulent flow online SPE LC-MS-MS method, compliant with the WADA's identification criteria, was developed and validated for the detection and confirmation of 80 stimulants or metabolites with limits of identification varying between 10 (or possibly lower) and 100 ng/mL. As several metabolites are common metabolites for multiple administered stimulants, this means that with this method, misuse of well over 100 compounds can be detected. As the developed method uses the same columns and mobile phases as our turbulent flow online SPE LC-MS-MS method for the confirmation of diuretics and masking agents, there is no need to change the configuration of the instrument when switching between the diuretics method and the developed stimulants method.

Stochastic dynamic mass spectrometric quantification of steroids in mixture - Part II

This paper deals with quantification of the following steroids in mixture: hydrocortisone (1), deoxycorticosterone (2), progesterone (3) and methyltestosterone (4) by means of mass spectrometry and implementing our innovative stochatic dynamic functional relationship between the analyte concentration in solution and the experimental variable intensity. The mass spectrometric data are correlated independently using chromatography. Chemometric analysis is carried out.

High-throughput liquid chromatography tandem mass spectrometry assay as initial testing procedure for analysis of total urinary fraction

In the recent years, a lot of effort was put into the development of multiclass initial testing procedures (ITP) to streamline analytical workflow in antidoping laboratories. Here, a high-throughput assay based on liquid chromatography-triple quadrupole mass spectrometry suitable for use as initial testing procedure covering multiple classes of compounds prohibited in sports is described. Employing a 96-well plate packed with 10 mg of weak cation exchange polymeric sorbent, up to 94 urine samples and their associated positive and negative controls can be processed in less than 3 h with minimal labor. The assay requires a 0.5-ml urine aliquot, which is subjected to enzymatic hydrolysis followed by solid phase extraction, evaporation, and reconstitution in a 96-well collection plate. With a 10-min run time, more than 100 analytes can be detected using electrospray ionization with polarity switching. The assay can be run nearly 24/7 with minimal downtime for instrument maintenance while detecting picogram amounts for the majority of analytes. Having analyzed approximately 28,000 samples, nearly 400 adverse analytical findings were found of which only one tenth were at or above 50% of the minimum required performance level established by the World Anti-Doping Agency. Compounds most often identified were stanozolol, GW1516, ostarine, LGD4033, and clomiphene, with median estimated concentrations in the range of 0.02-0.09 ng/ml (either as parent drug or a metabolite). Our data demonstrate the importance of using a highly sensitive ITP to ensure efficient antidoping testing.

Determination of pethidine of abuse and relevant metabolite norpethidine in urine by ultra-performance liquid chromatography-tandem mass spectrometry

Pethidine is an opiate agonist used orally and parenterally. Pethidine-containing drugs abuse is frequently encountered on health workers and patients. The analysis methods used to determine the abuse of pethidine are important for forensic toxicology. Pethidine is metabolized to norpethidine by the liver. Therefore, the determination of pethidine and norpethidine in urine is one of the methods to determine the abuse of pethidine. In this study, we have developed a precise, simple and rapid ultra-performance liquid chromatography-tandem mass spectrometer method for the determination of pethidine and norpethidine simultaneously. The developed method was validated in terms of selectivity and linearity which was in the range of 9-1800 ng/mL for both pethidine and norpethidine. The intra-assay and inter-assay accuracy and precision were found within acceptable limits of the EMA guideline. Lower limits of quantitation were 9 ng/mL for both pethidine and norpethidine. The developed method was successfully applied for the determination of both analytes in the real samples.

Identification and confirmation of diuretics and masking agents in urine by turbulent flow online solid-phase extraction coupled with liquid chromatography-triple quadrupole mass spectrometry for doping control

Diuretics can be misused to force diuresis to achieve weight loss or to mask the intake of a prohibited substance and are therefore prohibited by the World Anti-Doping Agency (WADA). For similar reasons other masking agents (vaptans, probenecid, etc.) are also prohibited by the WADA. The currently employed methods to detect diuretics in urine use extraction or dilute-and-shoot, combined with 1D- liquid chromatography (LC) high resolution mass spectrometry (MS) or LC-triple quadrupole MS. Dilute-and-shoot methods save time and work, but these methods encounter some problems (e.g., peak drift and matrix effect). Therefore, a 2D-LC-MS/MS application was developed, validated and evaluated as an alternative. The effect of a turbulent flow rate was studied by loading samples under different conditions and the turbulent flow rate was found to be more effective in removing matrix interferences. A correlation with the specific gravity was observed. A turbulent flow online solid phase extraction (SPE) method combined with LC-MS/MS for the detection of 50 diuretics and masking agents was developed and validated for identification purposes. This method combines the advantages of dilute-and-shoot while solving the issues of matrix effect and retention time shift. Furthermore, the presented method is compliant with WADA's identification criteria and can hence be used for screening and/or confirmation.

Renal tubular resistance is the primary driver for loop diuretic resistance in acute heart failure

BACKGROUND

Loop diuretic resistance is a common barrier to effective decongestion in acute heart failure (AHF), and is associated with poor outcome. Specific mechanisms underlying diuretic resistance are currently unknown in contemporary AHF patients. We therefore aimed to determine the relative importance of defects in diuretic delivery vs. renal tubular response in determining diuretic response (DR) in AHF.

METHODS AND RESULTS

Fifty AHF patients treated with intravenous bumetanide underwent a 6-h timed urine collection for sodium and bumetanide clearance. Whole-kidney DR was defined as sodium excreted per doubling of administered loop diuretic and represents the sum of defects in drug delivery and renal tubular response. Tubular DR, defined as sodium excreted per doubling of renally cleared (urinary) loop diuretic, captures resistance specifically in the renal tubule. Median administered bumetanide dose was 3.0 (2.0-4.0) mg with 52 (33-77)% of the drug excreted into the urine. Significant between-patient variability was present as the administered dose only explained 39% of variability in the quantity of bumetanide in urine. Cumulatively, factors related to drug delivery such as renal bumetanide clearance, administered dose, and urea clearance explained 28% of the variance in whole-kidney DR. However, resistance at the level of the renal tubule (tubular DR) explained 71% of the variability in whole-kidney DR.

CONCLUSION

Defects at the level of the renal tubule are substantially more important than reduced diuretic delivery in determining diuretic resistance in patients with AHF.

Method development and validation of HPLC tandem/mass spectrometry for quantification of perindopril arginine and amlodipine besylate combination in bulk and pharmaceutical formulations

A well-characterized and fully validated ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometric (UHPLC-ESI-MS/MS) method was developed to reliably analyze combination of perindopril arginine and amlodipine besylate in bulk and tablet formulations. The chromatographic separation was achieved on a Waters ACQUITY UPLC^® BEH C18 column with 1.7 μm particle packing which enabled the higher peak capacity, greater resolution, increased sensitivity, and higher speed of analysis using a volatile mobile phase ideally being at least 2 pH units below and above the perindopril arginine and amlodipine besylate pKa, respectively. Mass spectrometric detection was performed using electrospray ion source in positive ion polarity to profile the abundances of perindopril arginine and amlodipine besylate, using the transitions m/z 369 → m/z 172, and m/z 409 → m/z 238 for perindopril arginine and amlodipine besylate, respectively. Calibration curve was constructed over the range 0.25 – 500 ng/mL and 1.0 – 100 ng/mL for perindopril arginine and amlodipine besylate, respectively. The method was precise and accurate, and provided recovery rates > 80% for both compounds. Furthermore, the intra- and inter-assay precision in terms of % RSD was in between 0.1 – 3.7 for both perindopril arginine and amlodipine besylate. A specific, accurate, and precise UHPLC-MS/MS method for the determination of perindopril arginine and amlodipine besylate in bulk and tablet formulation.

Simplifying and expanding analytical capabilities for various classes of doping agents by means of direct urine injection high performance liquid chromatography high resolution/high accuracy mass spectrometry

So far, in sports drug testing compounds of different classes are processed and measured using different screening procedures. The constantly increasing number of samples in doping analysis, as well as the large number of substances with doping related, pharmacological effects require the development of even more powerful assays than those already employed in sports drug testing, indispensably with reduced sample preparation procedures. The analysis of native urine samples after direct injection provides a promising analytical approach, which thereby possesses a broad applicability to many different compounds and their metabolites, without a time-consuming sample preparation. In this study, a novel multi-target approach based on liquid chromatography and high resolution/high accuracy mass spectrometry is presented to screen for more than 200 analytes of various classes of doping agents far below the required detection limits in sports drug testing. Here, classic groups of drugs as diuretics, stimulants, β₂-agonists, narcotics and anabolic androgenic steroids as well as various newer target compounds like hypoxia-inducible factor (HIF) stabilizers, selective androgen receptor modulators (SARMs), selective estrogen receptor modulators (SERMs), plasma volume expanders and other doping related compounds, listed in the 2016 WADA prohibited list were implemented. As a main achievement, growth hormone releasing peptides could be implemented, which chemically belong to the group of small peptides (<2kDa) and are commonly determined by laborious and time-consuming stand-alone assays. The assay was fully validated for qualitative purposes considering the parameters specificity, robustness (rRT: <2%), intra- (CV: 1.7-18.4 %) and inter-day precision (CV: 2.3-18.3%) at three concentration levels, linearity (R²>0.99), limit of detection (0.1-25ng/mL; 3'OH-stanozolol glucuronide: 50pg/mL; dextran/HES: 10μg/mL) and matrix effects.

Simultaneous identification of abused drugs, benzodiazepines, and new psychoactive substances in urine by liquid chromatography tandem mass spectrometry

A literature search reveals no studies concerning simultaneous identification of commonly abused drugs, benzodiazepines, and new psychoactive substances in urine by liquid chromatography tandem mass spectrometry (LC-MS/MS). We developed and validated an LC-MS/MS method for simultaneous identification of multiple abused drugs, benzodiazepines, and new psychoactive substances in urine from suspected drug abusers. The instrument was operated in multiple-reaction monitoring using an electrospray ionization mode. Chromatograms were separated using an ACE5 C18 column on a gradient of acetonitrile. After liquid-liquid extraction, samples were passed through a 0.22-μm polyvinylidene difluoride filter before injection into the LC-MS/MS. The limits of quantitation ranged from 0.5 ng/mL to 31.3 ng/mL. The linearity ranged from 0.5 ng/mL to 200 ng/mL. The precision results were below 15.4% (intraday) and 18.7% (interday). The intraday accuracy ranged from 85.9% to 121.0%; interday accuracy ranged from 66.1% to 128.7%. The proposed method was applied to 769 urine samples. The most common three drugs identified were ketamine, amphetamine, and opiates. The drug positive rate for one or more drugs was 79.6%. Our results demonstrate the suitability of the LC-MS/MS method for simultaneous identification of multiple abused drugs, benzodiazepines, and new psychoactive substances in urine.

"Dilute-and-inject" multi-target screening assay for highly polar doping agents using hydrophilic interaction liquid chromatography high resolution/high accuracy mass spectrometry for sports drug testing

In the field of LC-MS, reversed phase liquid chromatography is the predominant method of choice for the separation of prohibited substances from various classes in sports drug testing. However, highly polar and charged compounds still represent a challenging task in liquid chromatography due to their difficult chromatographic behavior using reversed phase materials. A very promising approach for the separation of hydrophilic compounds is hydrophilic interaction liquid chromatography (HILIC). Despite its great potential and versatile advantages for the separation of highly polar compounds, HILIC is up to now not very common in doping analysis, although most manufacturers offer a variety of HILIC columns in their portfolio. In this study, a novel multi-target approach based on HILIC high resolution/high accuracy mass spectrometry is presented to screen for various polar stimulants, stimulant sulfo-conjugates, glycerol, AICAR, ethyl glucuronide, morphine-3-glucuronide, and myo-inositol trispyrophosphate after direct injection of diluted urine specimens. The usage of an effective online sample cleanup and a zwitterionic HILIC analytical column in combination with a new generation Hybrid Quadrupol-Orbitrap® mass spectrometer enabled the detection of highly polar analytes without any time-consuming hydrolysis or further purification steps, far below the required detection limits. The methodology was fully validated for qualitative and quantitative (AICAR, glycerol) purposes considering the parameters specificity; robustness (rRT < 2.0%); linearity (R > 0.99); intra- and inter-day precision at low, medium, and high concentration levels (CV < 20%); limit of detection (stimulants and stimulant sulfo-conjugates < 10 ng/mL; norfenefrine; octopamine < 30 ng/mL; AICAR < 10 ng/mL; glycerol 100 μg/mL; ETG < 100 ng/mL); accuracy (AICAR 103.8-105.5%, glycerol 85.1-98.3% at three concentration levels) and ion suppression/enhancement effects.

Anti-doping analyses at the Sochi Olympic and Paralympic Games 2014

The laboratory anti-doping services during XXII Winter Olympic and XI Paralympic games in Sochi in 2014 were provided by a satellite laboratory facility located within the strictly secured Olympic Park. This laboratory, established and operated by the personnel of Antidoping Center, Moscow, has been authorized by the World Anti-Doping Agency (WADA) to conduct doping control analyses. The 4-floor building accommodated the most advanced analytical instrumentation and became a place of attraction for more than 50 Russian specialists and 25 foreign experts, including independent observers. In total, 2134 urine and 479 blood samples were delivered to the laboratory and analyzed during the Olympic Games (OG), and 403 urine and 108 blood samples - during the Paralympic Games (PG). The number of erythropoietin tests requested in urine was 946 and 166 at the OG and PG, respectively. Though included in the test distribution plan, a growth hormone analysis was cancelled by the Organizing Committee just before the Games. Several adverse analytical findings have been reported including pseudoephedrine (1 case), methylhexaneamine (4 cases), trimetazidine (1 case), dehydrochloromethyltestosterone (1 case), clostebol (1 case), and a designer stimulant N-ethyl-1-phenylbutan-2-amine (1 case).

Methods for urine drug testing using one-step dilution and direct injection in combination with LC–MS/MS and LC–HRMS

The advent of LC combined with MS made it possible to design analytical methods for urine drug testing based on the very simple concept of diluting urine with an internal standard as the sole preparation procedure prior to instrumental analysis. The number of publications using this method design increased after the development of high-efficiency LC based on sub-2 μm particles. The success of this method design for drug testing, doping control and toxicological investigations of urine is now well documented and comprise both screening and confirmation methods. The nondiscriminating nature of this method design makes it even more attractive in combination with high-resolution MS for multicomponent target and general unknown analysis applications.

Detectability of new psychoactive substances, 'legal highs', in CEDIA, EMIT, and KIMS immunochemical screening assays for drugs of abuse

The increasing number of new psychoactive substances made available for recreational drug use has created a challenge for clinical toxicology and drug testing laboratories. As a consequence, the routine immunoassay drug testing may become less effective due to an increased occurrence of false negative and false positive screening results. This work aimed to extend the knowledge about analytical cross-reactivity of new substances in selected CEDIA, EMIT, and KIMS immunoassays for drugs-of-abuse screening. Urine standards were prepared by spiking blank urine with 45 new substances. Authentic urine samples from intoxication cases identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) were also studied. Several new psychoactive substances were demonstrated to display cross-reactivity in the immunoassays. CEDIA Amphetamine/Ecstasy and EMIT d.a.u. Amphetamine Class tests showed the highest reactivity towards the new drugs, which was expected since many have amphetamine-like structure and activity. In the samples from authentic cases, five new substances displayed 100% detection rate in the CEDIA Amphetamine/Ecstasy test. In conclusion, cross-reactivity data in routine urine drug screening immunoassays for a number of new psychoactive substances not studied before were reported. In both spiked and authentic urine samples, some new substances showed significant cross-reactivity and are thus detectable in the routine screening methods.

The challenges of LC–MS/MS analysis of opiates and opioids in urine

Opioids are some of the most commonly prescribed and abused drugs around the world. Primarily used for anesthesia or pain management, other opioids can also be used in the treatment of opioid addiction. Given these facts, clinicians often randomly test or monitor their patients to determine compliance or abstinence from these drugs via immunoassay methods. When a positive screen is obtained, a confirmatory assay is carried out and although the gold standard has been GC–MS, LC–MS/MS is fast becoming a valid and popular alternative. This review will discuss opioids, the complex metabolic pathways, the measurement of these drugs, the challenges involved and, finally, will describe some LC–MS/MS methods published from 2003 until 2013.

Clinical applications of fast liquid chromatography: a review on the analysis of cardiovascular drugs and their metabolites

One of the major challenges facing the medicine today is developing new therapies that enhance human health. To help address these challenges the utilization of analytical technologies and high-throughput automated platforms has been employed; in order to perform more experiments in a shorter time frame with increased data quality. In the last decade various analytical strategies have been established to enhance separation speed and efficiency in liquid chromatography applications. Liquid chromatography is an increasingly important tool for monitoring drugs and their metabolites. Furthermore, liquid chromatography has played an important role in pharmacokinetics and metabolism studies at these drug development stages since its introduction. This paper provides an overview of current trends in fast chromatography for the analysis of cardiovascular drugs and their metabolites in clinical applications. Current trends in fast liquid chromatographic separations involve monolith technologies, fused-core columns, high-temperature liquid chromatography (HTLC) and ultra-high performance liquid chromatography (UHPLC). The high specificity in combination with high sensitivity makes it an attractive complementary method to traditional methodology used for routine applications. The practical aspects of, recent developments in and the present status of fast chromatography for the analysis of biological fluids for therapeutic drug and metabolite monitoring, pharmacokinetic studies and bioequivalence studies are presented.