Evidence of repeated mirtazapine poisoning in children by hair analysis.

Mirtazapine is an antidepressant drug, used to treat depression, but also, in some specific conditions, to treat obsessive-compulsive disorder and anxiety. Although mirtazapine is not a hypnotic, it can make the subject feel drowsy. Children under the age of 18 should not take mirtazapine, but for some very special diseases, a physician can prescribe it for a limited period of time. The authors report a case involving 2 children (7- and 9-year-old) who were administered mirtazapine without consent by the mother, who was under daily therapy with this antidepressant. Hair specimens, collected from the children were tested by liquid chromatography coupled to tandem mass spectrometry for mirtazapine and its metabolite, N-desmethylmirtazapine, on 3 × 1 cm segments. The hair test results (3 × 1 cm segments) have demonstrated that both children have been repetitively exposed to mirtazapine for approximately the last 3 months before hair collection, with concentrations in the range 1.32-3.79 and 0.64-2.54 ng/mg for mirtazapine and N-desmethylmirtazapine, respectively. Environmental contamination was ruled out as the measured concentrations are highly variable according to the pattern of drug distribution and the washes were negative. Hair testing for drugs appears as an excellent diagnostic tool for child protection toward drug exposure.

Carbon Nanohorn Suprastructures on a Paper Support as a Sorptive Phase.

This article describes a method for the modification of paper with single-wall carbon nanohorns (SWCNHs) to form stable suprastructures. The SWCNHs form stable dahlia-like aggregates in solution that are then self-assembled into superior structures if the solvent is evaporated. Dipping paper sections into a dispersion of SWCNHs leads to the formation of a thin film that can be used for microextraction purposes. The coated paper can be easily handled with a simple pipette tip, paving the way for disposable extraction units. As a proof of concept, the extraction of antidepressants from urine and their determination by direct infusion mass spectrometry is studied. Limits of detection (LODs) were 10 ng/L for desipramine, amitriptyline, and mianserin, while the precision, expressed as a relative standard deviation, was 7.2%, 7.3%, and 9.8%, respectively.

Determination of olopatadine in human tears by hydrophilic interaction liquid chromatography-MS/MS method.

AIM: The objective of the study was development of hydrophilic interaction liquid chromatography-ESI/MS/MS method for the determination of olopatadine in tear matrix. MATERIALS & METHODS: Separation was performed on Acquity BEH amide column (2.1 × 100 mm, 1.7 µm). The mobile phase was consisted of 0.1% formic acid in water and acetonitrile. Mianserin hydrochloride was implemented as an internal standard. The artificial tear fluid was used as matrix. The tear samples were collected using Schirmer test strips. For the optimization of ultra pressure liquid chromatography conditions, Box-Benhken design was utilized. RESULTS: The optimal values of the ion source and collision cell parameters were found. Quantification was performed in multiple reaction monitoring mode. The optimized method was fully validated. CONCLUSION: The proposed method was utilized for monitoring of olopatadine in human tear.

Integrating a post-column makeup pump into preparative supercritical fluid chromatography systems to address stability and recovery issues during purifications.

Purification of many pharmaceutical compounds by supercritical fluid chromatography (SFC) has always been challenging because of degradation of compound during the isolation step in the presence of acidic or basic modifiers in the mobile phase. Stability of such acid or base-sensitive compounds could be improved by post-column addition of a solvent containing base or acid modifier as counter ion through a make-up pump respectively to neutralize the compound fraction without affecting the resolution. One such case study has been presented in this work where the stability of a base-sensitive compound was addressed by the addition of acidic co-solvent through the make-up pump. Details of this setup and the investigation of degradation of the in-house base-sensitive compound are discussed in this paper. In addition, poor retentivity and low recovery of many non-polar compounds in SFC eluting under low co-solvent percentage is another major concern. Even though the desired separation could be achieved with low percentage of co-solvent, it's difficult to get the proper recovery after purification due to precipitation of the sample and significant aerosol formation inside the cyclone. We have demonstrated the first-time use of a post-column make-up pump on SFC 350 system to introduce additional solvent prior to cyclone to avoid the precipitation, reduce the aerosol formation and thus improve the recovery of non-polar compounds eluting under less than 10% of co-solvent.

Poisoning suicide with ingestion of the pyrethroids alpha-cypermethrin and deltamethrin and the antidepressant mirtazapine: A case report.

This case report describes a death attributed to the intake of the pyrethroid insecticides, alpha-cypermethrin and deltamethrin, and the antidepressant mirtazapine. The autopsy findings showed absence of external traumatic injuries and internal generalized visceral congestion, edema and cyanosis. The toxicological results revealed the presence of a toxic concentration of mirtazapine (12.5mg/L and 10.7mg/L in blood and urine, respectively) and high concentrations of pyrethroids (2.46mg/L alpha-cypermethrin and 2.40mg/L deltamethrin in blood, and 0.41mg/L alpha-cypermethrin and 0.46mg/L deltamethrin in urine, respectively). Blood ethanol concentration was 0.75g/L. All the evidence - from autopsy, police investigation and toxicology - was consistent with the intentional self-harm of the deceased. The current case was determined and recorded as a poisoning suicide. Cause of death of the deceased was reported as the synergistic toxicity of the ingested pyrethroids and mirtazapine. The presence of a significant blood ethanol concentration was considered a secondary contributory factor to the fatal outcome. The case presented herein is the first death attributed to poisoning from ingestion of pyrethroids in combination with mirtazapine, with the intention of the victim to cause self-harm, with corresponding toxicology results.

[The identification and quantitative measurement of mirtazapine isolated from the biological material by high performance liquid chromatography].

The present study was designed to estimate the effectiveness of isolation of mirtazapine from the liver, blood, and urine. The conditions were developed for the identification and quantitative measurement of the isolated mirtazapine with the use of high performance liquid chromatography and detection from the UV-spectrum and mass-spectrometry. The retention time of mirtazapine isolated from the liver was 2.88 +/- 0.08 min. The straight-line equation within the range of mirtazapine concentrations from 1 to 20 mc/ml was characterized by the dependence: Y = 3.25 x 10(4)X - 6.27 x 10(3) (r = 0.9997). The study showed that it is possible to isolate 46.44 +/- 1.89% of mirtazapine present in the liver and 50.4 +/- 1.05% from blood using extraction by acetonitrile acidified with an 1 M hydrochloric acid solution. Chloroform extraction from urine at pH 7.0-8.0 releases 90.22 +/- 1.88% of mirtazapine.

Disopyramide and mianserin intoxication: a unique fatal case--review of the literature.

Lethal occurrence is exceptional after disopyramide or mianserin poisoning. A case of intentional lethal intoxication with these drugs was reported, as well as a review of the literature. Pre- and postmortem blood concentrations of disopyramide or mianserin were assessed in a woman who died from acute cardiac failure after ingestion. The premortem blood concentration of disopyramide alone was considered lethal, and a toxic premortem concentration of mianserin was observed that may have increased cardiovascular failure induced by disopyramide because the metabolism of both drugs is mediated via cytochrome P450. Moreover, it was shown that the postmortem redistribution of disopyramide was limited, as pre- and postmortem concentrations were 48 and 65 mg/L, respectively. As regards mianserin, redistribution was observed after death with pre- and portmortem concentrations at 0.23 and 0.79 mg/L, respectively. This case illustrates that if postmortem blood concentration of disopyramide is known, the premortem concentration can be deduced.

Simultaneous determination of 5 psychotropic drugs of various types in an autopsy case of acute multiple drug poisoning.

We attempted the simultaneous determination of 5 drugs, mirtazapine, sertraline, chlorpromazine, amoxapine and zolpidem, detected in a gas chromatography-mass spectrometry screening test in an autopsy case. The solid-phase extraction of the analytes from biological samples was achieved using Oasis(®)HLB cartridges (Waters, Milford, MA, USA). Gas chromatography was performed on a HP-5MS fused silica capillary column (30 m × 0.25 mm i.d., 0.25 µm film thickness, Agilent Technologies). The mass spectrometer was operated with an electron energy of 70 eV in electron impact mode. The qualitative and quantitative analyses were performed in full-scan mode and the selected ion monitoring mode, respectively. The total ion chromatogram showed good separation of these drugs. Linear graphs were obtained with good correlation coefficients for these drugs from 0.001 to 2.0 µg/mL (r(2)=0.9909-0.9986) using imipramine-d6 as an internal standard. The recoveries of these drugs were found to be 62.8-88.0% in spiked whole blood. Mirtazapine, sertraline, chlorpromazine, amoxapine and zolpidem were found in post-mortem samples of the deceased at concentrations of 2.67, 0.07, 0.25, 0.32 and 0.68 µg/mL, respectively. The concentration of mirtazapine was within the lethal level and those of amoxapine and zolpidem were within the toxic level. We diagnosed that the cause of death was acute multiple drug poisoning. The simple and practical procedure used in this study is useful for the simultaneous determination of psychotropic drugs of various types in post-mortem biological samples.

Micellar electrokinetic chromatographic method for mianserin hydrochloride and analysis of degradation products by mass spectrometry.

A simple, stability-indicating micellar electrokinetic chromatography (MEKC) method was developed and validated for the analysis of mianserin hydrochloride in coated tablets. The method employed (hydroxymethyl)aminomethane (TRIS) 50 mM to which sodium dodecyl sulfate (SDS) 50 mM was added at pH 10.6 as the electrolyte and the voltage applied was 25 kV. The capillary used was 48.5 cm long (40.0 cm effective length and 50.0 µm i.d.) and the detection wavelength was 220 nm. Tetracycline was used as internal standard. The method was validated in accordance with the International Conference on Harmonization (ICH) requirements, which involved specificity, linearity, precision, accuracy and robustness. The stability-indicating capability of the method was established by enforced degradation studies combined with peak purity assessment using photodiode array detection. The degradation products formed under photolytic and oxidative conditions were investigated by electrospray ionization mass spectrometry. The method was linear over the concentration range of 50-130 µg/mL. The method was precise as demonstrated by an inter-day and intra-day relative standard deviation of less than 2.0%. The proposed validated MEKC method showed recoveries between 98.16 and 102.80% of the nominal contents. The Plackett-Burman design was applied for the robustness test in order to examine potential sources of variability by screening a large number of factors in a relatively small number of experiments.

A semi-automated method for the integrated evaluation of half-life and metabolic soft spots of discovery compounds.

BACKGROUND: An integrated method that provides rates of both parent disappearance and metabolite formation was developed. RESULTS: Buspirone, mirtazapine and verapamil were used as model compounds in developing the method. Incubations were carried out on a robotic platform. Qualitative analysis of metabolites in 30 µM samples was conducted by data-dependent HPLC-MS/MS on a high-resolution instrument. Quantitative analysis of the parent compound and metabolites in 0.5 µM samples was conducted by full-scan MS(2) with product ion extraction using an ion trap mass spectrometer. Data generated for the compounds included half-life and intrinsic clearance of the parent molecule, characterization of metabolites and relative rates of metabolite formation. A correction factor was used to convert MS responses of metabolites in 0.5 µM samples to UV areas in order to compare relative metabolite concentrations. CONCLUSION: The approach allows for the investigation of a set of six compounds simultaneously, with a turnaround time of 1 week or less.

Photodegradation kinetics, cytotoxicity assay and determination by stability-indicating HPLC method of mianserin hydrochloride.

A stability-indicating HPLC method for the determination of mianserin hydrochloride in coated tablets was developed and validated. Also, drug photodegradation kinetics and cytotoxicity were determined. Chromatographic analyses were performed in an Ace RP-18 octadecyl silane column (250 mm x 4.6 mm i.d., particle size 5 microm) maintained at ambient temperature (25 degrees C). The mobile phase was composed of methanol, 50 mM monobasic potassium phosphate buffer and 0.3% triethylamine solution adjusted to pH 7.0 with phosphoric acid 10% (85:15, v/v) in isocratic mode at a flow rate of 1.0 mL x min(-1). The performed degradation conditions were: acid and basic media with HCl 1.0 M and NaOH 1.0 M, respectively, oxidation with H2O2 3% and the exposure to UV-C light. No interference in the mianserin hydrochloride elution was verified by degradation products formed. Linearity was assessed and ANOVA showed non-significant linearity deviation (p > 0.05). Adequate results were obtained for repeatability, intermediate precision, accuracy and robustness. The photodegradation kinetics of mianserin hydrochloride was evaluated in methanol. The degradation of mianserin could be better described as zero order kinetic (r = 0.9982). The UV-C degraded samples of mianserin hydrochloride were also studied in order to determine the preliminary cytotoxicity in vitro against mononuclear cells.

A fatal case of simultaneous ingestion of mirtazapine, escitalopram, and valproic acid.

Mirtazapine, escitalopram, and valproic acid are newer antidepressant drugs than traditional tricyclic antidepressants and are supposed to be less toxic. Nevertheless, intoxication cases due to their overdosage have been repeatedly reported. In the case presently reported, a 64-year-old woman with a previous history of chronic depression was found dead in her apartment. Several packages of pharmaceutical drugs were found, including mirtazapine, escitalopram, and valproic acid. During the autopsy, no evidence of natural disease or trauma was found to account for this death. In order to determine whether massive drug assumption might have determined a lethal intoxication, heart blood, urine, and gastric content were collected and submitted to toxicological analysis. Specific liquid chromatography-tandem mass spectrometry protocols were purposely developed and validated. Blood concentrations of mirtazapine, escitalopram, and valproic acid were 20.3, 65.5, and 417 mg/L, respectively, whereas urine concentrations were 17.0, 94.5, and 423 mg/L, respectively. High concentrations of these drugs were also detected in the gastric content, confirming their ingestion shortly before death. The agreement between authoptic examination by forensic pathologists and toxicological findings are consistent with the suicidal hypothesis, where the death arose by drug intoxication due to simultaneous high-dosage ingestion of mirtazapine, escitalopram, and valproic acid.

Determination of new antidepressants in pharmaceuticals by thin-layer chromatography with densitometry.

A new and simple TLC-densitometry method has been developed for the simultaneous separation of the two noradrenergic and specific serotonergic antidepressants mirtazapine and mianserine and validated for their determination in commercially available tablets. The method used TLC plates precoated with silica gel 60F254 as the stationary phase, and the mobile phase consisted of hexane-isopropanol-25% ammonia (70 + 25 + 5, v/v/v). Densitometric analysis was carried out in the absorbance mode at 280 nm. The method was validated in accordance with International Conference on Harmonization guidelines in terms of linearity, LOD, LOQ, precision, and accuracy. Calibration curves were linear (R2 > 0.9970) with respect to peak area in the concentration range of 500-2500 and 500-5000 ng/spot for mirtazapine and mianserine, respectively. The LODs were 20 and 35 ng/spot for mirtazapine and mianserine, respectively. The described method was successfully applied to the determination of mirtazapine and mianserine in their pharmaceutical formulations with recovery ranging from 99.83 to 101.20% of the labeled amount of the compounds. The proposed method can be used in routine QC of these drugs in pharmaceutical formulations.

A fatal case involving extremely high levels of ethylene glycol without elevation of its metabolites or crystalluria.

A unique case of an intentional overdose of ethylene glycol resulting in a fatality is described. The decedent had a very high concentration of ethylene glycol without elevated concentrations of its metabolites or crystalluria. The ethylene glycol concentrations in blood, urine, and vitreous fluid were 2340, 2261, and 1028 mg/dL, respectively. Osmolality of blood and vitreous fluid was also very high at 1426 and 534 mOsm/kg, respectively. No crystals were found in the urine. Furthermore, on the urine organic acids profile the ethylene glycol metabolites oxalic, glycolic, and glyoxylic acids were within the reference ranges. In addition to ethylene glycol, the decedent had an elevated level of mirtazapine, an antidepressant, and a low level of bupropion. It was estimated that the subject consumed 1034 g of ethylene glycol. To our knowledge, this is the first case of death from severe ethylene glycol poisoning in the absence of ethylene glycol metabolites or crystalluria.

Development and validation of a reversed-phase HPLC method for separation and simultaneous determination of process-related substances of mirtazapine in bulk drugs and formulations.

A simple and rapid reversed-phase high-performance liquid chromatographic method has been developed for the separation and simultaneous determination of related substances of mirtazapine in bulk drugs and pharmaceutical formulations. Six impurities, including one degradation product of mirtazapine, have been separated on a BDS Hypersil (4.6 x 250 mm; particle size 5 microm) column with a mobile phase consisting of 0.3% triethylamine (pH 3.0)-acetonitrile (78:22 v/v) eluted in an isocratic mode and monitored with a photo diode array detector at 215 nm. The chromatographic behavior of all the analytes was studied under variable compositions of different solvent systems, temperatures, buffer concentrations, and pH values. The method was validated in terms of accuracy, precision, and linearity. The inter- and intra-day assay precision was found to be < 0.98% [relative standard deviation; (RSD)] and the recoveries were in the range 95.54-102.22% with RSD < 2.21%. The correlation coefficients for calibration curves for mirtazapine as well as impurities were in the range of 0.9941-0.9999. The method was successfully applied to the analysis of commercial formulations and the recoveries of mirtazapine were in the range of 99.38-100.73% with < 0.52% RSD. The method is useful not only for rapid evaluation of the purity of mirtazapine, but also for the simultaneous determination of related substances in bulk drugs and pharmaceutical formulations.

Supported liquid membranes in hollow fiber liquid-phase microextraction (LPME)--practical considerations in the three-phase mode.

In this work, three-phase liquid-phase microextraction (LPME) based on a supported liquid membrane (SLM) sustained in the wall of a hollow fiber was investigated with special focus on optimization of the experimental procedures in terms of recovery and repeatability. Recovery data for doxepin, amitriptyline, clomipramine, and mianserin were in the range of 67.8-79.8%. Within-day repeatability data for the four basic drugs were in the range of 4.1-7.7%. No single factor was found to be responsible for these variations, and the variability was caused by several factors related to the LPME extractions as well as to the final HPLC determination. Although the volume of the SLM varied within 0.4-3.1% RSD depending on the preparation procedure, and the volume of the acceptor solution varied within 4.8% RSD, both recoveries and repeatability were found to be relative insensitive to these variations. Thus, the handling of microliters of liquid in LPME was not a very critical factor, and the preparation of the SLM was accomplished in several different ways with comparable performance. Reuse of hollow fibers was found to suffer from matrix effects due to built-up of analytes in the SLM, whereas washing of the hollow fibers in acetone was beneficial in terms of recovery, especially for the extraction of the most hydrophobic substances. Several of the organic solvents used in the literature as SLM suffered from poor long-term stability, but silicone oil AR 20 (polyphenylmethylsiloxane), 2-nitrophenyl octyl ether (NPOE), and dodecyl acetate (DDA) all extracted with unaltered performance even after 60 days of storage at room temperature.

Chirality in the new generation of antidepressants: stereoselective analysis of the enantiomers of mirtazapine, N-demethylmirtazapine, and 8-hydroxymirtazapine by LC-MS.

Mirtazapine is an antidepressant that acts specifically on noradrenergic and sertonergic receptors. A LC-MS method was developed that allows the simultaneous analysis of the R-(-)- and S-(+)-enantiomers of mirtazapine (MIR), demethylmirtazapine (DMIR), and 8-hydroxymirtazapine (8-OH-MIR) in plasma of MIR-treated patients. The method involves a 3-step liquid-liquid extraction, an HPLC separation on a Chirobiotic V column, and MS detection in electrospray mode. The limit of quantification (LOQ) for all enantiomers was 0.5 ng/mL, and the intra- and interday CVs were within 3.3% to 11.7% (concentration ranges 5-50 ng/mL). A method is also presented for the quantitative analysis of glucuroconjugated MIR and 8-OH-MIR. S-(+)-8-OH-MIR is present in plasma mainly as its glucuronide. Preliminary data suggest that in all patients, except in those comedicated with CYP2D6 inhibitors such as fluoxetine and thioridazine, R-(-)-MIR concentrations were higher than those of S-(+)MIR. Moreover, fluvoxamine seems also to inhibit the metabolism of MIR. Therefore, this method seems to be suitable for the stereoselective assay of MIR and its metabolites in plasma of patients comedicated with MIR and other drugs for routine and research purposes.

Spectrophotometric, spectrofluorimetric, HPLC and CZE determination of mirtazapine in pharmaceutical tablets.

Four analytical methods have been developed for the quality control of tablets containing mirtazapine: spectrophotometry, spectrofluorimetry, high performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). All the methods only require a simple extraction procedure of mirtazapine from the tablets before analysis. The concentration of mirtazapine in solutions was determined in the linearity range of 5-25 microg/ml at lambda=315 nm for spectrophotometry and at lambda=220 nm for HPLC and CZE. Spectrofluorimetric determinations were achieved at lambda(excitation)=328 nm and lambda(emission)=415 nm in the linearity range of 2-25 ng/ml. All the methods gave similar results and were validated for selectivity, linearity, precision and sensitivity. Spectrometric methods gave slightly higher RSD values (up to 2.54%). The four methods were directly and easily applied to the pharmaceutical preparation with accuracy, resulting from recovery experiments between 99.72% in HPLC and 101.47% in spectrofluorimetry.

Determination of mirtazapine in tablets by UV spectrophotometric and derivative spectrophotometric methods.

Mirtazapine, 1, 2, 3, 4, 10, 14b-hexahydro-2-methyl-pyrazino [2, 1-a] pyrido [2, 3-c] [G.L. Stimmel, J.A. Dopheide and S.M. Stahl, Pharmacotheraphy 17(1) (1997) 10] benzazepine, is a new and well tolerated antidepressant. It blocks pre-synaptic alpha2-adrenergic receptors and postsynaptic serotonin type 2 and type 3 receptors. The drug is rapid and completely absorbed after oral administration. Mirtazapine was analyzed by HPLC and gas chromatography with nitrogen-sensitive detection. In this study, mirtazapine was analyzed by using UV spectrophotometry, first and second order derivative spectrophotometry. The type of solvent, the degree of derivation, range of wavelength and n value were chosen in order to optimize the conditions. The concentration of mirtazapine in its methanolic solutions were determined between the wavelength range of 225-360 nm in the linearity range of 1-100, 2-100 and 1-120 microg ml(-1) by using the values obtained from UV. first-order derivative (n = 5, delta lambda = 17.5 nm) and second-order derivative (n = 9, delta lambda = 31.5 nm) spectrum of the substance, respectively. The developed UV Spectrophotometric, first-order and second-order derivative spectrophotometric methods were applied to a pharmaceutical preparation as tablet form. Developed UV and derivative UV spectrophotometric method in this study are accurate, sensitive, precise, reproducible and can be directly and easily applied to the pharmaceutical preparations.