Multiplexed therapeutic drug monitoring of antipsychotics in dried plasma spots by LC-MS/MS.

In this work, a convenient method for the therapeutic monitoring of seven common antipsychotic drugs in "dried plasma spot" samples has been developed. It is based on the liquid chromatography tandem mass spectrometry technique, operating in multiple reaction monitoring mode, and a straightforward procedure for the simultaneous extraction of all antipsychotics in a single step, with high extraction yield. The method was fully validated with proper accuracy, precision, selectivity and sensitivity, for all the drugs. Limits of quantification were 0.12, 1.09, 1.46, 1.47, 5.70, 1.32, 1.33 µg/L for haloperidol, aripiprazole, olanzapine, quetiapine, clozapine, risperidone, and paliperidone, respectively. Accuracy, intra- and interday precision values were <10% for all drugs at all concentration levels examined. The method was tested in the analysis of 30 plasma samples from real patients for each drug. The proposed analytical approach, by combining practical and logistical advantages of microsampling with liquid chromatography tandem mass spectrometry analytical performance, could offer an ideal strategy for accurate and timely therapeutic drug monitoring of antipsychotic drugs in most clinical settings, even in remote centers and/or in out-patient settings, bringing so many potential improvements in psychiatric patient care.

Bioactive molecules as authenticity markers of Italian Chinotto (Citrus×myrtifolia) fruits and beverages.

Chinotto (Citrus×myrtifolia) is a uncommon fruit belonging to the Citrus genus, mainly cultivated in small areas of the Italian territory, where the main use concerns the eponymous drink, marketed with the name of "Chinotto". The lack of information about this fruit highlights the usefulness of nutraceutical compound characterization, as well as the need to identify genuineness markers in derived commercial products. An analytical strategy based on SPE-HPLC-F was developed to identify and quantify different bioactive compounds in Chinotto (Citrus×myrtifolia) fruits and commercial beverages. The method was fully validated and successfully applied to the analysis of nutraceutical compounds in Chinotto fruits of Italian origin and in some Chinotto-based beverages, granting reliable and consistent data. The obtained results provided preliminary key information about the bioactive profiling of Citrus×myrtifolia and proved the suitability of the selected compounds as authenticity markers of derived commercial soft drinks.

Microextraction by packed sorbent (MEPS) to analyze catecholamines in innovative biological samples.

A new microextraction by packed sorbent (MEPS) procedure coupled to a high-performance liquid chromatographic method has been developed for quantitation of catecholamines (i.e. norepinephrine, epinephrine and dopamine) in innovative biological samples, namely dried plasma and urine spots. Analyses were carried out on a C18 reversed-phase column using a mobile phase composed of 2.5% methanol and 97.5% aqueous citrate buffer, containing octanesulfonic acid. Coulometric detection was used, setting the first analytical cell at -0.350 V and the second analytical cell at +0.400 V. Dried matrices were purified by means of a fast and feasible MEPS procedure, optimized on C18 sorbent and requiring only a small amount of biological sample. The availability of miniaturized procedures allowed satisfying specific requirements that ought to be considered during pre-treatment intended for catecholamine analysis. The extraction yield values were always higher than 85% and sensitivity was good, with a limit of quantitation of 100 pg mL(-1) for all the analytes. Satisfactory results were also obtained in terms of linearity, precision and accuracy. The method was successfully applied to dried plasma and urine spots derived from two socially diversified groups, namely psychiatric patients and poly-drug abusers, in comparison to healthy volunteers.

Dried blood spot testing: a novel approach for the therapeutic drug monitoring of ziprasidone-treated patients.

BACKGROUND: A novel analytical approach, based on dried blood spot (DBS) testing, has been developed, validated and applied for the first time to the analysis of ziprasidone (ZPR) for the therapeutic drug monitoring (TDM) of schizophrenic patients. DBS represent a more feasible but reliable matrix, alternative to blood and plasma. METHODS: The assays were carried out using an HPLC method with native fluorescence. Blood drops were applied to DBS cards and dried by microwaves, an internal standard solution was added to the DBS and 5-mm punches were cut out for analysis. ZPR was extracted from DBS with methanol, giving good extraction yields, precision and selectivity results. RESULTS: The method was applied with satisfactory results to DBS samples from psychiatric patients to determine ZPR levels for therapy optimization. CONCLUSION: This innovative methodology provides reliable and significant TDM information, with important advantages over classical blood sampling in terms of collection, storage and processing.

Δ9-Tetrahydrocannabinol-induced anti-inflammatory responses in adolescent mice switch to proinflammatory in adulthood.

Marijuana abuse is prominent among adolescents. Although Δ(9)-THC, one of its main components, has been demonstrated to modulate immunity in adults, little is known about its impact during adolescence on the immune system and the long-lasting effects in adulthood. We demonstrate that 10 days of Δ(9)-THC treatment induced a similar alteration of macrophage and splenocyte cytokines in adolescent and adult mice. Immediately at the end of chronic Δ(9)-THC, a decrease of proinflammatory cytokines IL- 1ß and TNF-α and an increase of anti-inflammatory cytokine IL-10 production by macrophages were present as protein and mRNA in adolescent and adult mice. In splenocytes, Δ(9)-THC modulated Th1/Th2 cytokines skewing toward Th2: IFN-γ was reduced, and IL-4 and IL-10 increased. These effects were lost in adult animals, 47 days after the last administration. In contrast, in adult animals treated as adolescents, a perturbation of immune responses, although in an opposite direction, was present. In adults treated as adolescents, a proinflammatory macrophage phenotype was observed (IL-1ß and TNF-α were elevated; IL-10 decreased), and the production of Th cytokines was blunted. IgM titers were also reduced. Corticosterone concentrations indicate a long-lasting dysregulation of HPA in adolescent mice. We measured blood concentrations of Δ(9)-THC and its metabolites, showing that Δ(9)-THC plasma levels in our mice are in the order of those achieved in human heavy smokers. Our data demonstrate that Δ(9)-THC in adolescent mice triggers immune dysfunctions that last long after the end of abuse, switching the murine immune system to proinflammatory status in adulthood.

Multi-matrix assay of the first melatonergic antidepressant agomelatine by combined liquid chromatography-fluorimetric detection and microextraction by packed sorbent.

A rapid and reliable analytical method has been developed to quantify the melatonergic antidepressant agomelatine in three matrices, and namely saliva, plasma and dried blood spots. The method is based on the use of liquid chromatography with fluorimetric detection exploiting the native fluorescence of agomelatine. For saliva and plasma samples an original microextraction by packed sorbent procedure was implemented obtaining satisfactory extraction yield of the analyte (always higher than 89%) and a good clean-up of the matrices. On the contrary, agomelatine was extracted from dried blood spots by suitable solvent microwave-assisted extraction and injected into chromatographic system. Satisfactory results in terms of sensitivity, linearity, precision, selectivity and accuracy were obtained. Thus, the developed method seems to be suitable for therapeutic drug monitoring of depressed patients under agomelatine therapy.

A fast and feasible microextraction by packed sorbent (MEPS) procedure for HPLC analysis of the atypical antipsychotic ziprasidone in human plasma.

An original high-performance liquid chromatographic method coupled to microextraction by packed sorbent (MEPS) was developed for the therapeutic drug monitoring (TDM) of psychiatric patients treated with the recent atypical antipsychotic ziprasidone. The chromatographic separation was achieved on a RP C18 column, using an isocratic mobile phase and setting the wavelength at 320nm. The analyte was extracted from human plasma by means of a fast and feasible innovative MEPS procedure, optimised on C2 sorbent and requiring only 100µL of biological sample. A second pre-treatment procedure, based on solid phase extraction (SPE), has been also developed for comparison. The availability of different pre-treatment procedures allows the choice of the one best suiting the specific clinical, economic and scientific needs. The extraction yield values were always higher than 90% and sensitivity was also good, with a limit of quantitation (LOQ) of 1ng/mL. The method was successfully applied to plasma samples from ten subjects undergoing therapy with ziprasidone, thus confirming its suitability for the TDM of psychiatric patients, in order to personalise their pharmacological treatments.

Evaluation of the pharmacokinetics, safety and clinical efficacy of sertraline used to treat social anxiety.

INTRODUCTION: Social anxiety disorder (SAD) is an emerging, often invalidating, syndrome with deep personal, social and psychological implications. While multiple treatment strategies exist, presently none of them can be considered superior to all others. AREAS COVERED: The aim of this review is to provide the latest information on sertraline (SRT), one of the most important selective serotonin reuptake inhibitors (SSRIs) currently used for the pharmacological therapy of SAD. A literature search was carried out with the keywords 'sertraline', 'social anxiety', 'social phobia' and 'clinical trials'. In this process, particular attention is paid to the pharmacokinetic characteristics of the drug and its safety in clinical use. EXPERT OPINION: SRT is an effective drug in the treatment of SAD, especially when used in combination with some form of psychological support. While it does not seem to be significantly more effective than other SSRIs, SRT could offer some peculiar advantages: for example, it has a long half-life, allowing a single daily administration, and seems to be particularly indicated for the control of specific symptoms of SAD.

Recent trends in the analysis of amino acids in fruits and derived foodstuffs.

The amino acid content of fruit and fruit-derived foods is studied intensely because of the contribution to nutritional value, aroma, taste and health-promoting effects and their possible use as markers of origin and authenticity. In this review, based on 101 references, the most recent trends in the analysis of amino acids are presented: the most important techniques, the different sample treatment procedures (including derivatisation) and the most frequent applications are described and compared. Pertinent publications were retrieved from Scopus and Web of Knowledge database searches lastly performed in February 2012 with the keywords "amino acid", "analysis", "liquid chromatography", "gas chromatography", "electrophoresis", "fruit", and "vegetables"; the time limit was set from the year 2000 onwards. Although amino acids have been analysed in foods for decades, new technical possibilities and advancements have allowed ever-increasing accuracy and targeting of the methods in order to overcome the challenges posed by the complex plant matrices and their high intrinsic variability.

Monitoring of chronic Cannabis abuse: an LC-MS/MS method for hair analysis.

An advanced analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), has been developed for the identification and determination in hair of Δ(9)-tetrahydrocannabinol together with its major metabolite 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol. Since the latter is formed endogenously, it allows the assessment of chronic use excluding passive exposure to Cannabis. The sample pre-treatment procedure is based on a feasible incubative extraction followed by a liquid-liquid extraction step. Chromatographic separation was performed using a reversed-phase column and gradient elution with a formic acid/acetonitrile/water mobile phase. The limits of quantitation and of detection were 3pg/mg and 1pg/mg, respectively, for both analytes. The method was successfully applied to the analysis of hair samples from Cannabis abusers; the analyte concentrations found ranged from 55 to 100pg/mg for Δ(9)-tetrahydrocannabinol and from 5 to 10pg/mg for 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol. Accuracy studies also gave satisfactory results (recovery>87%), thus confirming the suitability of the assay for chronic consumption monitoring.

Quantitative evaluation of auraptene and umbelliferone, chemopreventive coumarins in citrus fruits, by HPLC-UV-FL-MS.

An analytical strategy, based on the development of two HPLC methods with spectrophotometric (UV), spectrofluorometric (FL), and mass spectrometric (MS) detection, has been developed to investigate the presence of and to quantitate two important chemopreventive coumarins, auraptene and umbelliferone, in foodstuffs. The analytes were determined in fruits, and fruit parts, of plants belonging to the Citrus , Poncirus , and Fortunella genera, to test their nutraceutical potential. The method validation has been carried out according to international guidelines, with good results in terms of precision (RSD < 6.9%) and extraction yields (>91%). Application to the quantitative analysis of auraptene and umbelliferone in several kinds of citrus fruits was successful, providing reliable and consistent data. Exploiting three different kinds of detection, the analytical methodology proposed herein has been demonstrated to be sound but versatile, as well as reliable. Performances and results were compared and always found in good agreement among themselves. Thus, this approach is suitable for the identification and simultaneous quantitation of auraptene and umbelliferone in citrus fruits, with the aim of evaluating their nutraceutical potential.

Dried blood spots: liquid chromatography-mass spectrometry analysis of Δ9-tetrahydrocannabinol and its main metabolites.

A sensitive and selective HPLC-MS/MS method has been developed for the first time for the analysis of Δ(9)-tetrahydrocannabinol (the most important active cannabinoid) and its hydroxylated and carboxylated metabolites in human Dried Blood Spots (DBSs). The simultaneous determination of Δ(9)-tetrahydrocannabinol and its two main metabolites allows assessing the time elapsed after the drug intake and distinguishing between acute or former consumption. This is an important information in specific contexts such as "on street" controls by police forces. DBSs have been chosen as the optimal biological matrix for this kind of testing, since they provide information on the actual state of intoxication, without storage and transportation problems usually associated with classical blood testing. The analysis is carried out on a C8 reversed phase column with a mobile phase composed of 0.1% formic acid in a water/methanol mixture and an electrospray ionisation (ESI) source, coupled to a triple quadrupole mass spectrometer. The method was validated according to international guidelines, with satisfactory results in terms of extraction yields, precision, stability and accuracy. Application to real DBS samples from Cannabis abusers gave reliable results, thus confirming the methodology suitability for roadside testing.

A novel test using dried blood spots for the chromatographic assay of methadone.

A novel test has been developed for the analysis of methadone in dried blood spot specimens from patients undergoing methadone maintenance treatment. An isocratic reversed-phase high-performance liquid chromatography method with coulometric detection has been optimized for the determination of methadone. The clean-up of dried blood spots was performed by means of an original microextraction by packed sorbent procedure after microwave-assisted extraction of the drug with a suitable solvent. Extraction yields were satisfactory, always being higher than 90.0 %. The calibration curve was linear over the 4-500 ng mL(-1) concentration range. The method had satisfactory sensitivity (limit of quantitation of 4 ng mL(-1)), precision (relative standard deviation less than 5.8 %), selectivity and accuracy (recovery greater than 87.0 %). It was successfully applied to dried blood spot samples collected from heroin-addicted patients undergoing methadone maintenance therapy at dosages between 40 and 240 mg day(-1). The statistical analysis (Bland-Altman plot) showed that the results were in good agreement with those found from the analysis of plasma samples obtained from the same patients. Thus, the method has proved to be suitable for the monitoring of methadone by means of dried blood spots.

Validation of a dried blood spot LC-MS/MS approach for cyclosporin A in cat blood: comparison with a classical sample preparation.

A rapid, selective and sensitive bioanalytical method was developed and validated for cyclosporin A (CsA) in cat blood samples using dried blood spot (DBS) coupled with high pressure liquid chromatography hyphenated to positive electrospray tandem mass spectrometry (HPLC-ESI-MS/MS). CsA was quantified using a structural analog cyclosporin D (CsD) as internal standard in multiple reaction monitoring mode (MRM) using the transitions 1220→1203 for CsA and 1234→1217 for CsD. A 5-µL blood aliquot was spotted onto a DBS card, then after a drying step, blood spots were punched out from the cards and extracted with MeOH before injection into a LC-MS/MS system. The linear range of the method was 5-2000 ng/mL, with accuracy and precision within the FDA acceptance criteria (i.e., ±15% and ±20% for the lowest level). In the study presented herein a comparison was made between this new methodology, based on the use of DBS, and a previously developed solid phase extraction (SPE) procedure, applied to blood samples from a cat pharmacokinetic study. Good correlation (r(2)=0.97) was demonstrated between the data obtained with the two methods. The DBS methodology revealed to be cheaper, faster, less solvent-consuming and requiring less blood volume from animals than the previous SPE method. Thus, the proposed HPLC-ESI-MS/MS method, based on DBS, has demonstrated to be a suitable and advantageous approach for the analysis of CsA in cat blood.

Psychobiological responses to unpleasant emotions in cannabis users.

Aim of this paper is to investigate the psychobiological reactions to experimentally induced negative emotional states in active marijuana-dependent smokers and whether changes in emotional reactivity were reversed by prolonged abstinence. Twenty-eight patients were randomly included into group A (fourteen active marijuana-dependent smokers) or group B (fourteen abstinent marijuana-dependent subjects). Emotional response evaluation of group B subjects was assessed after 6 months of abstinence. Fourteen healthy volunteers, matched for age and sex, were used as controls. Psychometric and emotional response evaluations were performed by administering Symptoms Check List-90 and State-Trait Anxiety Inventory Y-1 (STAI). Neutral and unpleasant set of pictures selected from the international affective picture system and the Self-Assesment Manikin procedure (SAM) have been used to determine ratings of pleasure and arousal. Before and after the experimental session, blood samples were collected to determine ACTH and cortisol plasma levels. Active cannabis users displayed significantly higher levels of pleasantness SAM scores and lower levels of arousal SAM scores compared to abstinent cannabis users and controls in response to emotional task. In a close parallel with psychological data, hormonal findings indicate a persistent hyperactivity of hypothalamus-pituitary-adrenal (HPA) axis in cannabis users, particularly among active marijuana smokers, and an impaired hormonal reaction to negative emotions, in comparison with healthy subjects. The capacity of the HPA axis to respond to stressful stimuli/negative emotions seems to be only partially recovered after 6 months of abstinence. Ours findings, although obtained in a small number of subjects, suggest an association between active cannabis use, subjective reduced sensitivity to negative emotions and threat and HPA axis dysfunction.

Ketoconazole-associated preferential increase in dopamine D2 receptor occupancy in striatum compared to pituitary in vivo: role for drug transporters?

Membrane transporters such as P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are efflux pumps that remove drugs from the brain back to the peripheral blood compartment, serving as a functional component of the blood-brain barrier (BBB). We report here that coadministration of the P-gp and BCRP inhibitor ketoconazole with risperidone may preferentially increase D2 receptor occupancy in the striatum compared to pituitary. Four male patients with schizophrenia or schizoaffective disorder who had received at least 4 prior injections of the long-acting risperidone at a stable dose of 25 to 50 mg participated in this positron emission tomography study. Multiple-dose ketoconazole coadministration reduced the P-gp activity as shown by fexofenadine oral challenge. Importantly, we found a strong statistical trend in this sample of 4 subjects who consistently showed a decrease in striatal fluorine 18 (F)-fallypride binding (an indication of increased D2 receptor occupancy) after ketoconazole coadministration (P = 0.057), whereas the pituitary (a region that lies outside the BBB) F-fallypride binding did not change (P = 0.99). These observations warrant further research with selective drug transporter inhibitors. We suggest that in neuroimaging studies, the pituitary drug occupancy can serve as a useful new "positive control" to evaluate whether drug occupancy is preferentially increased in brain regions that fall inside the BBB after cotreatment with P-gp and BCRP inhibitors. This is a noteworthy study design consideration regarding the future clinical testing of novel adjunct interventions aimed at modulating membrane transporter function at the BBB, with the goal of augmenting drug access into the brain compartment, particularly in treatment-resistant psychiatric illness.

Content of melatonin and other antioxidants in grape-related foodstuffs: measurement using a MEPS-HPLC-F method.

The strong antioxidant activity of melatonin is well known and it is important to investigate its presence and levels in different foodstuffs, for the purpose of evaluating their nutraceutical properties. As a contribution towards this goal, an original analytical method has been developed for the simultaneous determination of melatonin and other indolic and phenolic antioxidants (including trans- and cis-resveratrol, ferulic acid, tryptophan, serotonin and 5-hydroxyindoleacetic acid) in grape-related foodstuffs and beverages: namely grape, grape juice, must, wine and grappa (Italian pomace brandy). These foodstuffs represent an important part of the diet, both traditionally and in recent times, especially in Mediterranean countries and could be (at least in part) responsible for the beneficial effects involved in the 'French paradox'. The analytical method is based on high-performance liquid chromatography coupled to fluorescence detection, exploiting the native fluorescence of the analytes. A C8 column was used as the stationary phase, while the mobile phase was composed of acidic phosphate buffer and acetonitrile; fluorescence intensity was monitored at λ=386nm while exciting at λ=298nm. The sample pretreatment was carried out by a fast and reliable microextraction by packed sorbent (MEPS) procedure. After validation, the method was applied to the analysis of melatonin and other antioxidants in food and beverages derived from grape, with very good results being obtained. Thus, this methodology may represent a promising tool for the evaluation of the antioxidant properties of nutraceuticals and functional foods.

Combined liquid chromatography-coulometric detection and microextraction by packed sorbent for the plasma analysis of long acting opioids in heroin addicted patients.

The sublingual combination of buprenorphine and naloxone (Suboxone(®)) and Methadone Maintenance Therapy have been found effective in treating heroin addiction. A new analytical method suitable for the simultaneous determination of buprenorphine, norbuprenorphine, methadone and naloxone in human plasma by means of liquid chromatography with coulometric detection has been developed. The chromatographic separation was achieved with a phosphate buffer-acetonitrile mixture as the mobile phase on a cyano column. The monitoring cell of the coulometric detector was set at an oxidation potential of +0.600 V. A rapid clean-up procedure of the biological samples using a microextraction by packed sorbent technique has been implemented, employing a C8 sorbent inserted into a syringe needle. The extraction yield values were satisfactory for all analytes (>85%). The calibration curves were linear over a range of 0.25-20.0 ng mL(-1) for buprenorphine and norbuprenorphine, 3.0-1000.0 ng mL(-1) for methadone and 0.13-10.0 ng mL(-1) for naloxone. The sensitivity was also high with limits of detection of 0.08 ng mL(-1) for both buprenorphine and norbuprenorphine, 0.9 ng mL(-1) for methadone and 0.04 ng mL(-1) for naloxone. The intraday and interday precision data were always satisfactory. The method was successfully applied to plasma samples obtained from former heroin addicts treated with opioid replacement therapy.

Rapid assays of clozapine and its metabolites in dried blood spots by liquid chromatography and microextraction by packed sorbent procedure.

A novel analytical approach has been developed for the determination of clozapine and its metabolites in dried blood spots on filter paper, using a chromatographic method coupled with a microextraction by packed sorbent procedure. The analytes were separated on a RP-C18 column using a mobile phase composed of 20% methanol, 16% acetonitrile and 64% aqueous phosphate buffer. Coulometric detection was used, setting the guard cell at +0.050 V, the first analytical cell at -0.200 V and the second analytical cell at +0.500 V. Clozapine and its metabolites were extracted from dried blood spots with phosphate buffer and, then, a microextraction by packed sorbent procedure for the sample clean-up was implemented obtaining good extraction yields. The calibration curve was linear over the 2.5-1000 ng mL(-1) blood concentration ranges for all the analytes. The method validation gave satisfactory results in terms of sensitivity, precision, selectivity and accuracy. The analytical method was successfully applied to dried blood spots from several psychiatric patients for therapeutic drug monitoring purpose.

Analysis of risperidone and 9-hydroxyrisperidone in human plasma, urine and saliva by MEPS-LC-UV.

Risperidone is currently one of the most frequently prescribed atypical antipsychotic drugs; its main active metabolite 9-hydroxyrisperidone contributes significantly to the therapeutic effects observed. An original analytical method is presented for the simultaneous analysis of risperidone and the metabolite in plasma, urine and saliva by high-performance liquid chromatography coupled to an original sample pre-treatment procedure based on micro-extraction by packed sorbent (MEPS). The assays were carried out using a C8 reversed-phase column and a mobile phase composed of 73% (v/v) acidic phosphate buffer (30 mM, pH 3.0) containing 0.23% triethylamine and 27% (v/v) acetonitrile. The UV detector was set at 238 nm and diphenhydramine was used as the internal standard. The sample pre-treatment by MEPS was carried out on a C8 sorbent. The extraction yields values were higher than 92% for risperidone and 90% for 9-hydroxyrisperidone, with RSD for precision always lower than 7.9% for both analytes. Limit of quantification values in the different matrices were 4 ng/mL or lower for risperidone and 6 ng/mL or lower for the metabolite. The method was successfully applied to plasma, urine and saliva samples from psychotic patients undergoing therapy with risperidone, with satisfactory accuracy results (recovery>89%) and no interference from other drugs. Thus, the method seems to be suitable for the therapeutic drug monitoring of schizophrenic patients using the three different biological matrices plasma, urine and saliva.