Electromembrane extraction of chlorprothixene, haloperidol and risperidone from whole blood and urine.

Separation of antipsychotic drugs from whole blood and urine is of great importance for clinic and forensic laboratories. In this work, chlorprothixene, haloperidol and risperidone representing the first and second generations of antipsychotic drugs were studied. Among them, chlorprothixene and risperidone were investigated for the first time by electromembrane extraction (EME). After the screening, 2-nitrophenyl octyl ether (NPOE) was used as the supported liquid membrane (SLM). The EME performance for spiked water (pH 2), whole blood and urine was tested and optimized individually. Using NPOE and 60 V, efficient EME was achieved from urine and whole blood with trifluoroacetic acid as the acceptor solution. The equilibrium time required for EME was dependent on the sample matrices. The steady-state of EME was reached in 30 min and 20 min for whole blood and urine, respectively. At steady-state, the EME recoveries of the targets from different sample matrices were satisfactory, and were in the range of 74%-100%. The proposed EME approach combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was evaluated using whole blood and urine. The obtained linearity was 1-200 ng mL-1, and the coefficient of determination (R2) was ≥ 0.9853 for haloperidol and ≥ 0.9936 for chlorprothixene and risperidone. The limit of detection (LOD) and accuracy for all the targets ranged from 0.2-0.6 ng mL-1 and 102%-110%, respectively, and the repeatability at low (1 ng mL-1), medium (10 ng mL-1) and high (200 ng mL-1) concentration was ≤ 12% (RSD). Finally, the validated approach was successfully used to determine chlorprothixene, risperidone and haloperidol in whole blood and urine from rats, which were treated with chlorprothixene, risperidone and haloperidol at low therapeutic dose, respectively.

Highly sensitive and selective method for the rapid determination and preconcentration of haloperidol by using a magnetite-molecularly imprinted polymer.

A sensitive and selective method based on the determination of haloperidol with the usage of magnetite-molecularly imprinted polymer and high-resolution liquid chromatography has been developed. This novel method is rapid as the detection procedure for haloperidol can be completed within a total time of 1 h. The same imprinted polymer can be used for the determination of haloperidol at least 20 times. The proposed method has been succesfully applied to synthetic urine and serum samples and the recoveries of the spiked samples were in the range of 94.7-100.7%. The limit of detection and limit of quantification of the method were 2.25 and 7.50 µg/L, respectively. Linearity of the calibration graph was observed within the range of 10-250 µg/L. By combining the high capacity, high selectivity, and reusability of the magnetic adsorbent with the dynamic calibration range, high sensitivity and high resolution of liquid chromatography with quadrupole time-of-flight mass spectrometry, the proposed method is an ideal method for the determination and preconcentration of trace levels of haloperidol. A magnetite-molecularly imprinted polymer has been used for the first time as a selective adsorbent for the determination of haloperidol.

Impact of ß-Glucuronidase Mediated Hydrolysis on Haldol® Urinalysis.

Reports have suggested that patients with mental health disorders including major depressive disorder and schizophrenia have dramatically low adherence levels to prescribed medications. Patients on haloperidol (Haldol®) therapy, regardless of their disease, were found to have higher adherence levels-though still strikingly low. This work shows that high levels of the glucuronidated form of haloperidol are present in patient urine samples. Time-of-Flight (TOF) mass spectrometry experiments are consistent with both the presence of haloperidol glucuronide and that hydrolysis of haloperidol patient urine samples leads to significantly increased concentrations of free haloperidol. Urine samples collected from patients prescribed haloperidol were tested with and without hydrolysis revealing a significant increase in the number of patients testing positive when the samples were hydrolyzed before analysis. These data demonstrate that hydrolysis greatly improves the sensitivity and consistency of results for patients on haloperidol therapy resulting in positivity data that strongly correlates with the dosage form administered.

Urine testing for antipsychotics: a pilot trial for a method to determine detection levels.

OBJECTIVE: The goal of the present study was to demonstrate that the analytical assay of interest can detect antipsychotics in human urine specimens. METHOD: Forty inpatients treated with haloperidol, quetiapine, risperidone, or olanzapine were recruited to participate in a one visit study. During the study visit, demographic and clinical information was collected as well as one urine sample that was forwarded to the Ameritox Laboratory and assayed for the presence of antipsychotic medications and/or metabolites. Urine samples were analyzed to determine detection sensitivity for four antipsychotic medications and their metabolites (risperidone, quetiapine, olanzapine, and/or haloperidol) using Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry. RESULTS: All urine samples produced positive results for the antipsychotic(s) the participants were known to be taking. Urine concentrations (level of quantification) for parent drugs ranged from <25-417 ng/mL for haloperidol, <25-4017 ng/mL for quetiapine, 0-997 ng/mL for risperidone, and 57-700 ng/mL for olanzapine. CONCLUSION: The analytical assay produced by Ameritox, Ltd using Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry can qualitatively detect antipsychotics in human urine specimens. The present study highlights the potential utility of the urine assay to help monitor adherence to antipsychotic medications.

Monitoring haloperidol exposure in body fluids and hair of children by liquid chromatography-high-resolution mass spectrometry.

BACKGROUND: Haloperidol, 4-[4-(4-chlorophenyl)-4-hydroxy-1-piperidinyl]-1-(4-fluorophenyl)-1-butanone (HP), one of the most widely used antipsychotics in the treatment of schizophrenia, mania, and other psychiatric disorders, is frequently encountered in cases of unintentional pediatric intoxication because the ingestion of a small amount can cause significant toxic effects in children. For monitoring HP in suspected ingestions, a liquid chromatography-high-resolution mass spectrometry method has been developed and validated in urine, blood, and hair samples. METHODS: The analyte was extracted from 1 mL blood or urine by liquid/liquid extraction and from 5 mg of hair by micropulverized extraction; gradient elution on an Atlantis T3 column was realized using HP-d4 as an internal standard. Positive ion electrospray ionization and high-resolution mass spectrometry determination were performed in an Orbitrap mass spectrometer. RESULTS: The method exhibited a r > 0.999 in the studied ranges (0.1-50 ng/mL in urine and blood and 0.1-50 ng/mg in hair) and a limit of quantification of 0.1 ng/mL for urine and blood and 0.1 ng/mg for hair; intra-assay and interassay relative SDs were always more than 18%. The method was applied to determine haloperidol in 3 children who were admitted to emergency departments. HP concentrations ranged from 2 to 21 ng/mL in urine, from not detected to 4.9 ng/mL in blood, and from 0.37 to 0.73 ng/mg in hair samples. CONCLUSIONS: The utilization of high-resolution/high-accuracy mass spectrometry in full scan mode allowed the identification of HP metabolites in urine and blood, thus unequivocally documenting the exposure to the drug. HP metabolites were structurally characterized by high-resolution multiple mass spectrometry. For the first time, a HP metabolite was detected in hair.

Determination of haloperidol in biological samples using molecular imprinted polymer nanoparticles followed by HPLC-DAD detection.

In this study an extraction procedure using molecular imprinted polymer nanoparticles for the determination of haloperidol in biological samples is proposed. The haloperidol imprinted polymer nanoparticles were synthesized successfully by precipitation polymerization in a flask containing haloperidol as a template, ethyleneglycoldimethacrylate as a crosslinking agent, methacrylic acid as a functional monomer, and 2,2'-azobisisobutyronitrile as an initiator. The leached and unleached polymer nanoparticles have been characterized by infrared spectroscopy and scanning electron microscopy. The effect of different variables such as the pH of solution, uptake and elution time, type, and the least amount of eluent for elution of haloperidol from polymer was evaluated. Extraction efficiencies more than 97% were obtained by elution of the polymer with 1.5 mL of methanol-acetic acid-trifluoroacetic acid 79.9:20:0.1. Under optimal conditions maximum adsorption capacity was obtained 153.84 mg g(-1). The detection limit of the proposed procedure was between 0.2 and 0.35 µg L(-1). Finally this method was applied to the determination of haloperidol in plasma and urine samples and satisfactory results were achieved (RSD<6.9%).

Determination of haloperidol in biological samples with the aid of ultrasound-assisted emulsification microextraction followed by HPLC-DAD.

A rapid and simple quantitative method for preconcentration and determination of haloperidol in biological samples was developed using ultrasound-assisted emulsification microextraction, based on the solidification of floating organic droplet combined with HPLC-DAD. The effects of several factors were investigated. A total of 30 µL of 1-undecanol as an extraction solvent was injected slowly into a glass-centrifuge tube containing 4 mL alkaline sample solution that was located inside the ultrasonic water bath. The formed emulsion was centrifuged and the fine droplets of solvent were floated at the top of the test tube, then it was cooled in an ice bath and the solidified solvent was transferred into a conical vial, after melt, the analysis of the extract was carried out by HPLC. Under the optimal conditions, the extraction efficiencies were more than 90% and the preconcentration factors were obtained between 119-122. The LOQs were obtained between 4-8 µg/L and the calibration curves were linear within the range of 4-1000 µg/L. Finally this method was applied to the determination of haloperidol in plasma and urine samples in the range of µg/L and satisfactory results were achieved (RSDs <7%).

[Identification of haloperidol and tiapride in the urine with thin layer chromatography].

How to identify haloperidol and tiapride in the urine by thin layer chromatography was proposed. Optimal systems of solvents were selected by chromatographic mobility of the substances studied in 14 solvents with different polarity. The findings allowed making an optimal choice of the composition and proportion of the solvents. Diethylamine, as a basic modifier, was introduced in the system of solvents. This improved chromatographic mobility of haloperidol and tiapride. Optimal mobile phases, developers were found, the threshold of detectability of the substances in the given conditions was established. The techniques were used for identification of haloperidol and tiapride in the samples from model urine mixture in the presence of non-identified endogenic compounds. They are characterized by rapid performance, selectivity, sensitivity and good reproducibility and can be introduced into practice of chemicotoxicological laboratories.

Assay of the anti-psychotic drug haloperidol in bulk form, pharmaceutical formulation and biological fluids using square-wave adsorptive stripping voltammetry at a mercury electrode.

The cyclic voltammetric behavior of haloperidol at a hanging mercury drop electrode was studied in Britton-Robinson buffer series of pH 2.5-11 containing 40% (v/v) ethanol. A single two-electron irreversible cathodic peak was obtained which attributed to reduction of the CO double bond. In addition, a small enhanced adsorptive pre-wave was observed at less negative potentials over the pH range 3.5-11. Controlled adsorptive accumulation of haloperidol onto the hanging mercury drop electrode provided the basis for its direct trace assay in bulk form, pharmaceutical formulation and human biological fluids using square-wave adsorptive cathodic stripping voltammetry. Following preconcentration of bulk haloperidol onto the HMDE a well-developed square-wave cathodic peak was generated in Britton-Robinson buffer especially at pH values 9-10; its peak current showed a linear dependence on the concentration of haloperidol over the range 1 x 10(-9)M to 1.5 x 10(-6)M depending on the preconcentration duration. The procedural parameters for assay of haloperidol were studied. The achieved limits of detection (LOD) and quantitation (LOQ) were 3.83 x 10(-10)M and 1.28 x 10(-9)M bulk haloperidol, respectively. The procedure was successfully applied to assay haloperidol in tablets (Safinace) and in spiked human serum and urine. LOD of 3.3 x 10(-9)M and 5.46 x 10(-9)M, and LOQ of 1.10 x 10(-8) and 1.82 x 10(-8)M haloperidol were achieved in spiked human serum and urine samples, respectively.

Liquid chromatographic-mass spectrometric determination of haloperidol and its metabolites in human plasma and urine.

Haloperidol and its two metabolites, reduced haloperidol and 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP) in human plasma and urine were analyzed by HPLC-MS using a new polymer column (MSpak GF-310), which enabled direct injection of crude biological samples without pretreatment. Recoveries of haloperidol and reduced haloperidol spiked into plasma were 64.4-76.1% and 46.8-50.2%, respectively; those for urine were 87.3-99.4% and 94.2-98.5%, respectively; those of CPHP for both samples were not less than 92.7%. The regression equations for haloperidol, reduced haloperidol and CPHP showed good linearity in the ranges of 10-800, 15-800 and 400-800 ng/ml, respectively, for both plasma and urine. Their detection limits were 5, 10 and 300 ng/ml, respectively, for both samples. Thus, the present method was sensitive enough for detection and determination of high therapeutic and toxic levels for haloperidol and its metabolites present in biological samples.

Comparison of SSI with APCI as an interface of HPLC-mass spectrometry for analysis of a drug and its metabolites.

Sonic spray ionization (SSI) was compared with atmospheric pressure chemical ionization (APCI) as an interface of high-performance liquid chromatography (HPLC)-mass spectrometry (MS) for sensitive analyses of a neuroleptic drug, haloperidol and its two metabolites, such as reduced haloperidol and 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP), in biological samples. For both SSI and APCI interfaces, HPLC-MS-MS gave higher sensitivity than HPLC-MS. The sensitivities by HPLC-SSI-MS-MS for haloperidol and reduced haloperidol were 100 and 30 times higher, respectively, than those by HPLC-APCI-MS-MS; no spectrum with recognizable peaks was obtained for CPHP with the APCI interface. Therefore, detection limits and regression equations were examined by the HPLC-SSI-MS-MS for human plasma and urine samples spiked with the above drug and its metabolites. Haloperidol, reduced haloperidol, and CPHP showed good linearity in the ranges of 5-800, 10-800, and 100-800 ng/mL, respectively, for both human plasma and urine; their detection limits were 2.5, 5, and 75 ng/mL, respectively, using a new polymer HPLC column which enabled direct application of biological samples.

Gas chromatographic-mass spectrometric analysis of veterinary tranquillizers in urine: evaluation of method performance.

A method for analysis of veterinary tranquillizers in urine using gas chromatography-mass spectrometry (GC-MS) is described. Detection limits are 5 microg/l for ketamine, azaperone and the phenothiazines (chlor-, aceto- and propionylpromazine), 10 microg/l for haloperidol, 20 microg/l for xylazine and 50 microg/l for azaperol, recoveries for all analytes were higher than 70%. Method performance in terms of within-batch, between-days and between-analysts reproducibility was studied and found to be acceptable. Compliance with European Union criteria for confirmation of GC-MS "positive" results is evaluated and discussed.

Chirality of reduced haloperidol in humans.

In vitro, cytosolic human ketone reductases catalyse the stereospecific (i.e. >99%) formation of S(-) reduced haloperidol (RHP) from haloperidol (HP). Whether this situation is reflected in patients taking the drug is unknown. In this study in nine patients taking HP, only 73.2+/-18.2% of the RHP excreted in urine was the S(-) enantiomer. Thus, enzymes other than cytosolic ketone reductases must be responsible for the formation of the minor enantiomer.

Two pyridinium metabolites of haloperidol are present in the brain of patients at post-mortem.

We have shown in patients taking the antipsychotic drug haloperidol (HP) that two pyridinium metabolites (HPP+ and RHPP+) are present in blood and urine in nM concentrations. These metabolites are structurally analogous to MPP+, the neurotoxic metabolite of the well-known parkinsonian-producing protoxin, MPTP. In this study we measured the concentrations of HPP+ and RHPP+ in seven regions of the brain (putamen, substantia nigra, globus pallidus, caudate, hippocampus, cerebellum and occipital cortex) obtained at post-mortem from three patients who were taking HP before death. Blood, urine, and bile from one patient were analysed as well. HPP+ was present in all regions (except for substantia nigra in one patient and globus pallidus in another); the amount/g ranged from 1.6-8.3 pMol but there was no preferential sequestration of the metabolite in dopaminergic regions. Similarly, RHPP+ was present relatively uniformly in all regions; the amount/g ranged from 1.1-7.6 pMol. The concentrations of HPP+ and RHPP+ in one patient were 24 and 13 nM in blood, 660 and 230 nM in urine, and 13.0 and 1.4 microM in bile, respectively. The presence of these pyridinums in brain adds another important piece of information to the case that, at least for HP, metabolite-induced neurotoxicity could contribute to the extrapyramidal side-effects in patients receiving long-term therapy.

Quantitative analysis of two pyridinium metabolites of haloperidol in patients with schizophrenia.

OBJECTIVE: A pyridinium metabolite (HPP+) of the neuroleptic drug haloperidol has been identified in rats and in the urine of patients. The purpose of this study was to measure the steady-state blood and plasma concentrations and daily urinary excretion of HPP+ in patients treated with haloperidol. METHODS: HPP+ was measured by HPLC with fluorescence detection. The chromatograms also revealed the presence of a previously unknown pyridinium species, which was identified in urine by liquid chromatography/mass spectrometry/mass spectrometry as 4-(4-chlorophenyl)-1-4-(4-fluorophenyl)-4-hydroxybutylpyridinium (RHPP+). Concentrations of RHPP+ were then measured by HPLC. RESULTS: The steady-state concentrations of HPP+ or RHPP+ in blood and plasma from 34 patients were virtually identical. The plasma concentrations of each metabolite were related to the daily dose of haloperidol and to its plasma concentrations. Nonlinearity in the elimination of RHPP+ was suggested by the increase in the ratio between RHPP+ and HPP+ plasma concentrations with dose or steady-state concentrations of haloperidol. The concentrations of RHPP+ in plasma and urine generally exceeded those of HPP+; the ratio between them in plasma ranged from 0.9 to 14.1. The daily urinary excretion of HPP+ and RHPP+ accounted for 0.40% +/- 0.18% and 2.3% +/- 1.4% of the haloperidol dose, respectively. The renal clearance of each species was 4.5 +/- 2.5 and 11.3 +/- 5.3 L/hr, respectively. CONCLUSIONS: The presence of these pyridinium species in humans raises the concern that they may be neurotoxic in a manner similar to the dopaminergic pro-neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

Metabolic studies on haloperidol and its tetrahydropyridine analog in C57BL/6 mice.

The neuroleptic agent haloperidol (HP) is biotransformed in humans to a pyridinium metabolite, HPP+, that displays neurotoxic properties resembling those of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-derived neurotoxic pyridinium metabolite MPP+. We report here that HP and its tetrahydropyridine dehydration product 4-(4-chlorophenyl)-1-[4-(4-fluorophenyl)-4-oxobutyl]-1,2,3,6- tetrahydropyridine (HPTP) are metabolized in vivo by the MPTP-susceptible C57BL/6 mouse to several pyridinium metabolites including HPP+ and the 4-(4-chlorophenyl)-1-[4-(4-fluorophenyl)-4-hydroxybutyl]pyridinium species RHPP+, the pyridinium species corresponding to reduced haloperidol (RHP), a major circulating metabolite of HP. Atmospheric pressure ion-spray (API) mass spectral data also suggest the formation of fluorophenyl ring-hydroxylated derivatives of these two pyridinium metabolites. Furthermore, HPLC tracings reveal the presence of HPP+, RHPP+, and two phenolic pyridinium metabolites in brain tissue extracts of HPTP, but not HP, treated mice. The neurotoxic potential of MPTP-type pyridinium species suggests that these metabolites may contribute to some of the neurological disorders observed in humans undergoing chronic HP treatment.

Investigation of drug metabolism using capillary electrophoresis with photodiode array detection and online mass spectrometry equipped with an array detector.

The application of capillary electrophoresis (CE) with photodiode array detection (DAD) and on-line CE-mass spectrometry (CE-MS) equipped with a position and time resolved (PATRIC) focal plane detector for analysis of both in vitro and in vivo drug metabolism is demonstrated. Separation of metabolites derived from the neuroleptic drug haloperidol, by CE, using a simple, volatile run buffer containing 50 mM ammonium acetate with 10% methanol and 1% acetic acid is reported. The potential utility of CE-DAD for screening drug metabolite mixtures derived from hepatic microsomal incubations is demonstrated for haloperidol (HAL). Also the potential problems associated with using this technology to screen human urine samples for HAL metabolites is discussed. Furthermore, the usefulness of CE-MS and CE-electrospray ionization skimmer collision induced dissociation-MS (CE-ESI-CID-MS) in identification and structure elucidation of HAL metabolites derived from both a guinea pig hepatic microsomal incubation and urine from a patient treated with 0.5 mg/day of HAL is shown. The utility of such an approach in the general area of clinical pharmacology is also discussed.

Determination of the pyridinium metabolite derived from haloperidol in brain tissue, plasma and urine by high-performance liquid chromatography with fluorescence detection.

A sensitive and selective method for the determination of the pyridinium metabolite (HPP+) derived from the antipsychotic drug haloperidol (HP) in brain tissue, plasma and urine using high-performance liquid chromatography with fluorescence detection is described. The HPP+ present in biological samples was extracted using a Sep-Pak C18 cartridge. Recoveries of HPP+ ranged from 78 to 90%. Final separation and quantitative estimations of HPP+ were achieved on a C18 reversed-phase column employing a mobile phase of acetonitrile-30 mM ammonium acetate (40:60, v/v) containing 10 mM triethylamine and adjusted to pH 3 with trifluoroacetic acid. The fluorescence detection utilized an excitation wavelength of 304 nm and an emission wavelength of 374 nm. Standard curves were linear in the range of 2.5-100 ng/ml for brain tissue homogenate and plasma samples and 10-500 ng/ml for urine samples. The detection limit of HPP+ was about 1 ng/ml in all biological samples. The concentrations of HPP+ in brain tissue, plasma and urine from HP-treated rats were determined using this method.

Identification of potentially neurotoxic pyridinium metabolite in the urine of schizophrenic patients treated with haloperidol.

Evidence that the parkinsonian inducing agent MPTP is biotransformed to a pyridinium species that selectively destroys nigrostriatal neurons in humans and subhuman primates has prompted studies to evaluate the metabolic fate of the structurally related neuroleptic agent haloperidol. With the aid of a highly sophisticated atmospheric pressure ionspray HPLC/MS/MS assay, unambiguous evidence has been obtained for the presence of the haloperidol pyridinium species in extracts of urine obtained from haloperidol-treated patients and in extracts of NADPH-supplemented human liver microsomal incubation mixtures containing haloperidol. The potential significance of the formation of this putative neurotoxic pyridinium species is considered.

Identification of a potentially neurotoxic pyridinium metabolite of haloperidol in rats.

In vivo metabolic studies have revealed that haloperidol is converted to the corresponding pyridinium metabolite which has been characterized in both urine and brain tissues isolated from haloperidol treated rats. Unlike the corresponding conversion of the structurally related Parkinsonian inducing agent MPTP to the ultimate neurotoxic pyridinium metabolite MPP+, the oxidative biotransformation of haloperidol is not catalyzed by MAO-B. Microdialysis studies in the rat indicate that intrastriatal administration of this pyridinium metabolite is about 10% as effective as MPP+ in causing the irreversible depletion of striatal nerve terminal dopamine. The results point to the possibility that some of the neurological disorders observed in experimental animals and man during the course of chronic haloperidol treatment may be mediated by this pyridinium metabolite.