A novel and sensitive UPLC-MS/MS method to determine mequitazine in rat plasma and urine: Validation and its application to pharmacokinetic studies.

The aim of this study was to develop an analytical method to determine mequitazine in rat plasma and urine. Mequitazine was separated by UPLC-MS/MS equipped with a Kinetex core-shell C18 column (50 × 2.1 mm, 1.7 µm) using 0.1% (v/v) aqueous formic acid and acetonitrile containing 0.1% (v/v) formic acid as a mobile phase by gradient elution at a flow rate of 0.3 mL/min. Quantitation of this analysis was performed on a triple quadrupole mass spectrometer employing electrospray ionization technique operating in multiple reaction monitoring positive ion mode. Mass transitions were m/z 323.3 → 83.1 for mequitazine and 281.3 → 86.3 for imipramine as internal standard. Liquid-liquid extraction with ethyl acetate and protein precipitation with methanol were used for sample extraction. Chromatograms showed that the method had high resolution, sensitivity and selectivity without interference from plasma constituents. Calibration curves for mequitazine in rat plasma and urine were 0.02-200 ng/mL, showing excellent linearity with correlation coefficients (r2 ) >0.99. Both intra- and inter-day precisions (CV%) were within 4.08% for rat plasma and urine. The accuracies were 99.58-102.03%. The developed analytical method satisfied the criteria of international guidance. It could be successfully applied to pharmacokinetic studies of mequitazine after oral and intravenous administration to rats.

A molecularly imprinted polymer based chemiluminescence array sensor for one-step determination of phenothiazines and benzodiazepines in pig urine.

The residues of phenothiazines and benzodiazepines in foods of animal origin are dangerous to consumers. For inspection of their abuses, this study for the first time reported on the use of a chemiluminescence array sensor for the simultaneous determination of four phenothiazines and five benzodiazepines in pig urine. Two molecularly imprinted polymers were coated in different wells of a conventional 96-well microtiter plate as the recognition reagents. After sample loading, the absorbed analytes were initiated directly by using an imidazole enhanced bis(2,4,6-trichlorophenyl)oxalate-hydrogen peroxide system to emit light. The assay process consisted of only one sample-loading step prior to data acquisition, so one test was finished within 10 min. The limits of detection for the nine drugs in the pig urine were in a range of 0.1 to 0.6 pg/mL, and the recoveries from the fortified blank urine samples were in a range of 80.3 to 95%. Furthermore, the sensor could be reused six times. Therefore, this sensor could be used as a simple, rapid, sensitive and reusable tool for routine screening for residues of phenothiazines and benzodiazepines in pig urine.

Combination of poly(diallyldimethylammonium chloride) and hydroxypropyl-γ-cyclodextrin for high-speed enantioseparation of phenothiazines by capillary electrophoresis.

High-speed capillary electrophoresis (CE) enables the simple, rapid, and inexpensive analysis of large sets of chiral samples in the pharmaceutical industry. Hence, we developed a novel method for separating enantiomers of d,L-phenothiazines simply and rapidly, based on using poly(diallyldimethylammonium chloride) (PDDAC) as an additive and hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector in capillary electrophoresis. Adding 0.9% PDDAC to the background electrolyte generated a stable, high, and reversed electroosmotic flow (EOF). Hp-γ-CD not only worked as a complexing agent to increase the chiral resolution between d,L-phenothiazines but also decreased the effective electrophoretic mobility of these drugs. Combining PDDAC and Hp-γ-CD as buffer additives enabled CE to achieve a high-speed enantioseparation of five pairs of d,L-phenothiazines. A decrease in capillary length and an increase in the intensity of the electric field further shortened the separation time. When the background electrolyte contained 0.9% PDDAC, 5mM Hp-γ-CD, and 75 mM formic acid (pH 3.0), enantioseparation of the d,L-phenothiazines was attained within 230 s by applying a capillary length of 32.5 cm and an electric field of 292 V cm(-1). The limit of detection (LOD) of the d,L-phenothiazines at a signal-to-noise ratio of 3 ranged from 2 to 8 µM. We demonstrated the feasibility of this method by detecting the five pairs of d,L-phenothiazines in urine samples.

Hollow fiber-liquid phase microextraction combined with gas chromatography for the determination of phenothiazine drugs in urine.

A simple method of hollow fiber-liquid phase microextraction (HF-LPME) combined with gas chromatography (GC) was developed for the analysis of four phenothiazine drugs (promethazine, promazine, chlorpromazine and trifluoperazine) in human urine samples. All variables affecting the extraction of target analytes including organic solvent type, stirring rate, extraction time, extraction temperature, pH of sample solution and ionic strength were carefully studied and optimized. Under the optimal conditions, the analytical performance of HF-LPME-GC-flame photometric detector (FPD) and HF-LPME-GC-flame ionization detector (FID) were evaluated and compared. The results showed that the HF-LPME-GC-FID was more sensitive than HF-LPME-GC-FPD for the determination of four target phenothiazine drugs, while the signal peak shape and resolution obtained by HF-LPME-GC-FPD was better than that obtained by HF-LPME-GC-FID. HF-LPME-GC-FPD/FID was successfully applied for the assay of the interested phenothiazine drugs in urine sample, and the excretion of the drugs was also investigated by monitoring the variation of the concentration of chlorpromazine in urine of a psychopath within 8 h after drug-taking. The proposed method provided an effective and fast way for the therapeutic drug monitoring (TDM) of phenothiazine.

Molecularly imprinted polymers as analyte sequesters and selective surfaces for easy ambient sonic-spray ionization.

The use of a molecularly imprinted polymer (MIP) as a selective surface for ambient mass spectrometry is demonstrated. The MIP is used to sequester target analytes from urine and easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is shown to be able to efficiently desorb the analytes from the MIP surface and then transfer them in protonated forms to the gas phase for MS analysis. A set of five phenothiazines (chlorpromazine, perphenazine, triflupromazine, thioridazine and prochlorperazine) were chosen from a proof-of-principle class of drug samples. A chlorpromazine-imprinted methacrylic polymer was synthesized and used to prepare a MIP probe. The MIP-EASI-MS technique using acidified methanol as solvent has been shown to allow quantification of all five drugs in urine with LOQ of ca. 1 micromol L(-1).

Determination of phenothiazine derivatives in human urine by using ionic liquid-based dynamic liquid-phase microextraction coupled with liquid chromatography.

A simple and rapid method for the determination of seven phenothiazines derivatives (chlorpromazine, promethazine, levomepromazine, prochlorperazine, trifluoperazine, fluphenazine and thioridazine) in human urine samples is presented. The analytes are extracted from the sample in 50 microL of the ionic liquid 1-butyl-3-methyl-imidazolium hexafluorophosphate working in an automatic flow system under dynamic conditions. The chemical affinity between the extractant and the analytes allows a good isolation of the drugs from the sample matrix achieving at the same time their preconcentration. The separation and detection of the extracted compounds is accomplished by liquid chromatography and UV detection. The proposed method is a valuable alternative for the analysis of these drugs in urine within the concentration range 0.07-10 microg mL(-1). Limits of detection were in the range from 21 ng mL(-1) (thioridazine) to 60 ng mL(-1) (levomepromazine). The repeatability of the proposed method expressed as RSD (n=5) varied between 2.2% (levomepromazine) and 3.9% (chlorpromazine).

Metabolic fate of phenothiazine in the marmoset (Callithrix jacchus).

The fate of [35S]-phenothiazine, a veterinary anthelmintic, has been investigated in the adult male marmoset (Callithrix jacchus) following oral administration. A near complete recovery of radioactivity (c. 95%) was achieved in 0-3 days, with just over one-third of the dose (c. 37%) being present in the urine and the remainder (c. 58%) being accounted for in the faeces. The majority of the urinary radioactivity (c. 91%) was present as conjugates, tentatively identified as phenothiazine N-glucuronide and leucophenothiazone sulphate. Smaller amounts of phenothiazone, thionol, phenothiazine sulphoxide and unchanged phenothiazine were also identified. The only compound identified in the faeces was unchanged phenothiazine.

[Application of the clinoid dehydration method in forensic medical expert examination of poisoning with narcotic and strong medicine preparations].

The method of clinoid dehydration of biological fluids along with pH measurement is shown to be suitable for the diagnosis of narcotic intoxication and poisoning with narcotic and potent agents. The data obtained by this and conventional methods are compared. Diagnostically significant signs of narcotic intoxication are deduced from the hemogram of a dry blood droplet and serum pH values.

[Extended suicidal poisoning with carbamazepine and phenothiazine derivatives]. / Rozszerzone samobójcze zatrucie karbamazepina i fenotiazynami.

UNLABELLED: Two cases (woman and man) of the extended suicidal poisonings with carbamazepine and phenothiazine derivatives are presented. Drug's blood concentrations during poisoning were monitored. We examine correlation between patient's general status and the drug's blood concentrations, carbamazepine and phenothiazine derivatives interaction due to young, healthy people who received no earlier treatment. MATERIAL AND METHODS: blood samples for toxicological examinations were collected at 0, 12, 24 and 48 hours after admission. Carbamazepine was determined using FPIA method and phenothiazines derivatives by HPLC-DAD. The highest blood concentrations were for carbamazepine: 30.92 mg/l (woman) and 20.95 ng/ml (man); for phenothiazine derivatives: 927 ng/ml (woman) and 733 ng/ ml (man). CONCLUSIONS: In both cases severe central nervous depression was observed due to summed action of the drugs. Sex and individual differences in cytochromes activities should have influence to carbamazepine metabolism and faster elimination time in woman. In the case of phenothiazine derivatives faster elimination time in man was observed. The differences in elimination times between compared drugs confirm their different metabolic routes.

Determination of phenothiazines in pharmaceutical formulations and human urine using capillary electrophoresis with chemiluminescence detection.

A CE instrument coupled with chemiluminescence (CL) detection was designed for the determination of promethazine hydrochloride (PTH) and promazine hydrochloride (PMH) in real samples. An important enhancement of the CL emission of luminol with potassium ferricyanide was observed in the presence of these phenothiazines; so this system was selected for their detection after CE separation. Parameters affecting the electrophoretic separation were optimized in a univariate way, while those affecting CL detection were optimized by means of a multivariate approach based on the use of experimental designs. Chemometrics was also employed for the study of the robustness of the factors influencing the postcolumn CL detection. The method allows the separation of the phenothiazines in less than 4 min, achieving LODs of 80 ng/mL for PMH and 334 ng/mL for PTH, using sample injection by gravity. Electrokinetic injection was used to obtain lower LODs for the determination of the compounds in biological samples. The applicability of the CE-CL method was illustrated in the determination of PTH in pharmaceutical formulations and in the analysis of PMH in human urine, using a previous SPE procedure, achieving an LOD of 1 ng/mL and recoveries higher than 85%.

Development and validation of a capillary electrophoresis method for the determination of phenothiazines in human urine in the low nanogram per milliliter concentration range using field-amplified sample injection.

A capillary zone electrophoresis (CZE) method with ultraviolet-visible detection has been established and validated for the determination of five phenothiazines: thiazinamium methylsulfate, promazine hydrochloride, chlorpromazine hydrochloride, thioridazine hydrochloride, and promethazine hydrochloride in human urine. Optimum separation was obtained on a 64.5 cm x 75 microm bubble cell capillary using a buffer containing 150 mM tris(hydroxymethyl)aminomethane and 25% acetonitrile at pH 8.2, with temperature and voltage of 25 degrees C and 20 kV, respectively. Naphazoline hydrochloride was used as an internal standard. Field-amplified sample injection (FASI) has been applied to improve the sensitivity of the detection. Considering the influence of parameters affecting the on-line preconcentration (nature of preinjection plug, sample solvent composition, injection times, and injection voltage) and due to the significant interactions among them, in this paper we propose for the first time the application of a multivariate approach to carry out the study. The optimized conditions were as follows: preinjection plug of water for 7 s at 50 mbar, electrokinetic injection for 40 s at 6.2 kV, and 32 microm of H3PO4 in the sample solvent. Also, a solid-phase extraction (SPE) procedure is developed to obtain low detection limits and an adequate selectivity for urine samples. The combination of SPE and FASI-CZE-UV allows adequate linearities and recoveries, low detection limits (from 2 to 5 ng/mL), and satisfactory precisions (3.0-7.2% for an intermediate RSD %).

Determination of phenothiazines in human body fluids by solid-phase microextraction and liquid chromatography/tandem mass spectrometry.

Eleven phenothiazine derivatives with heavy side-chains were found to be extractable from human whole blood and urine samples by solid-phase microextraction (SPME) with a polyacrylate-coated fiber. The fiber was then injected into the desorption chamber of an SPME-liquid chromatography (LC) interface for LC/tandem mass spectrometry (MS/MS) with positive ion electrospray (ES) ionization. All compounds formed base peaks due to [M + 1](+) ions by LC/ES-MS/MS. By use of LC/ES-MS/MS, the product ions produced from each [M + 1](+) ion showed base peaks due to side-chain liberation. Selected reaction monitoring (SRM) and selected ion monitoring (SIM) were compared for the detection of the 11 phenothiazine derivatives from human whole blood and urine. SRM showed much higher sensitivity than SIM for both types of sample. Therefore, a detailed procedure for the detection of drugs by SRM with SPME-LC/MS/MS was established and carefully validated. The extraction efficiencies of the 11 phenothiazine derivatives spiked into whole blood and urine were 0. 0002-0.12 and 2.6-39.8%, respectively. The regression equations for the 11 phenothiazine derivatives showed excellent linearity with detection limits of 0.2-200 ng ml(-1) for whole blood and 4-22 pg ml(-1) for urine. The intra- and inter-day precisions for whole blood and urine samples were not greater than 15.1%. The data obtained after oral administration of perazine or flupentixol to a male subject are presented.

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.

[Evaluation of an automated liquid chromatograph permitting toxicologic screening of biological fluids]. / Evaluation d'un automate de chromatographie liquide permettant un screening toxicologique dans les liquides biologiques.

This study evaluated an automated high performance liquid chromatography algorithm that allows identification of 330 substances and metabolites in biological fluids. We assessed its ability to detect in urine and gastric lavage fluids the main psychotropic drugs ingested with suicidal intent. Antidepressants and most of the phenothiazines were recognised; identification of benzodiazepines was more uncertain. Compared to EMIT techniques, chromatography is less sensitive, but allows precise identification of the offending poison, quantifies the amount, and allows broad toxicological screening of pharmacological classes inaccessible to the EMIT technique.

The metabolism of piperidine-type phenothiazine antipsychotic agents. II. Sulforidazine in dog and human.

1. The metabolism of sulforidazine was studied in female dogs and adult male humans after oral administration of 37.5 mg and 25.0 mg, respectively. 2. Metabolites in organic extracts of dog urine were separated by h.p.l.c. and individually collected prior to mass spectrometric analysis, while organic extracts of human urine were directly subjected to plasmaspray h.p.l.c.-mass spectrometric determination. In the case of phenolic metabolites, the urinary extracts from both species were derivatized with a silylating reagent (with or without prior enzymic hydrolysis) and subsequently analysed by h.p.l.c.-mass spectrometry. The structures of metabolites with the exception of phenols were confirmed by comparison of their mass spectra and chromatographic behaviours with those of authentic standards. 3. The compounds identified in urine of both species were sulforidazine, two diastereomers of sulforidazine ring sulphoxide, the lactam of sulforidazine ring sulphoxide and a phenolic derivative of sulforidazine, whereas sulforidazine N-oxide and the lactam of sulforidazine were identified only in human urine. Moreover the phenolic metabolite was present in human urine in both unconjugated and conjugated forms, whereas dog urine had only the conjugated form. 4. Sulforidazine and some of its major metabolites were quantified by an h.p.l.c. method. The mean urinary excretions (0-48 h) of sulforidazine were similar in human (n = 3) and dog (n = 3) (5.9 +/- 0.7% and 7.2 +/- 1.9%), as were the excretions of sulforidazine ring sulphoxide (13.2 +/- 4.6% and 13.3 +/- 4.4%), while the lactam of sulforidazine ring sulphoxide was a major metabolite only in human (7.5 +/- 2.8% and < 0.1%). The lactam of sulforidazine was a minor metabolite in human. 5. The metabolites observed in human urine were similar to those previously reported in rat, except that sulforidazine N-oxide was found only in human, whereas the two diastereomers of N-desmethylsulforidazine ring sulphoxide were observed only in rat. These data suggest that rat may be a more suitable animal than dog for further study of the metabolism of the piperidine ring of sulforidazine.

Sensitive determination of phenothiazines in body fluids by gas chromatography with surface ionization detection.

Fourteen phenothiazine derivatives were tested for their detection by gas chromatography (GC) with surface ionization detection (SID). The sensitivity of GC-SID was highest with trimeprazine and levomepromazine, which contain aliphatic tertiary amino side chains, and lowest with thiethylperazine and thioproperazine, which contain sulphur residues. Chlorpromazine, trimeprazine and promazine showed excellent linearity between the SID response and the drug amount in the range 0.25-3.0 pmol on-column. Their detection limits were as low as ca. 5-10 pg (15-30 fmol) on-column (250-500 pg per ml of body fluid). A detailed procedure for isolation of phenothiazines from human whole blood and urine using Sep-Pak C18 cartridges, before the GC with SID, is also presented. The recoveries of the drugs (100 pmol), which were added to 1 ml of whole blood or urine, were more than 79%. The baselines remained steady as the column temperature was increased.

Albuminuric growth failure. A case of Munchausen syndrome by proxy.

A five-year-old girl presented with profound growth failure, lethargy, vomiting and acidosis. A diagnosis of Munchausen syndrome by proxy was made after the demonstration of egg albumin, diphenhydramine and phenothiazine metabolites in her urine. Growth improved dramatically, but a subsequent child in the family died of sudden infant death syndrome.

The metabolism of piperidine-type phenothiazine antipsychotic agents. I. Sulforidazine in the rat.

1. The metabolism of the piperidine-type, phenothiazine antipsychotic agent, sulforidazine, was studied in female rats after a 20 mg/kg single oral dose. 2. Compounds identified in urine were sulforidazine, sulforidazine ring sulphoxide, the lactam of sulforidazine, the lactam of sulforidazine ring sulphoxide, two diastereomers of N-desmethylsulforidazine ring sulphoxide and a phenolic derivative of sulforidazine. 3. Metabolites were separated by h.p.l.c. prior to mass spectrometric or g.l.c.-mass spectrometric analysis. Except in the case of the phenolic metabolite, structures were confirmed by direct comparison of electron impact mass spectra and chromatographic behaviour with those of authentic samples. To facilitate identification of the phenolic metabolite the crude urinary extract was treated with a silylating reagent and analysed by h.p.l.c.-mass spectrometry with a plasmaspray interface. 4. Despite the availability of authentic standards of sulforidazine N-oxide and sulforidazine N,S-dioxide neither of these compounds could be identified in urinary extracts obtained from rats. 5. Sulforidazine underwent extensive metabolism in rats as only 2.3 +/- 0.4% (n = 5) of the dose was present as unchanged sulforidazine in 24 h urine. The lactam of sulforidazine (0.1 +/- 0.1%) was a minor metabolite whereas the lactam of sulforidazine ring sulphoxide was 3.2 +/- 2.6% dose. 6. Sulforidazine sulphoxide (12.1 +/- 1.6%) was a major metabolite and its diastereomers were present in similar amounts.

Light-induced racemization: artifacts in the analysis of the diastereoisomeric pairs of thioridazine 5-sulfoxide in the plasma and urine of patients treated with thioridazine.

The ring sulfoxidation of thioridazine (THD), a widely used neuroleptic agent, yields two diastereoisomeric pairs, fast- and slow-eluting (FE and SE) thioridazine 5-sulfoxide (THD 5-SO). Until now, studies in which concentrations of these metabolites were measured in THD-treated patients have revealed no significant differences in their concentrations. Preliminary experiments in our laboratory had shown that sunlight and, to a lesser extent, dim daylight led to racemization and probably also to photolysis of the diastereoisomeric pairs as measured by high-performance liquid chromatography. Similar results were also obtained with direct UV light (UV lamp). In appropriate light-protected conditions, THD, northioridazine, mesoridazine, sulforidazine, and FE and SE THD 5-SO were measured in 11 patients treated with various doses of THD for at least 1 week. Significantly higher concentrations of the FE stereoisomeric pair were found. The concentration ratios THD 5-SO (FE)/THD 5-SO (SE) ranged from 0.89 to 1.75 in plasma and from 1.15 to 2.05 in urine. Because it is known that the ring sulfoxide contributes to the cardiotoxicity of the drug even more potently than the parent compound does, these results justify further studies to determine whether there is stereoselectivity in the cardiotoxicity of THD 5-SO.