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Jordi Ortuño

    Jordi Ortuño

    The 8(th) GCC Closed Forum for Bioanalysis was held in Baltimore, MD, USA on 5 December 2013, immediately following the 2013 AAPS Workshop (Crystal City V): Quantitative Bioanalytical Methods Validation and Implementation - The 2013... more
    The 8(th) GCC Closed Forum for Bioanalysis was held in Baltimore, MD, USA on 5 December 2013, immediately following the 2013 AAPS Workshop (Crystal City V): Quantitative Bioanalytical Methods Validation and Implementation - The 2013 Revised FDA Guidance. This GCC meeting was organized to discuss the contents of the draft revised FDA Guidance on bioanalytical method validation that was published in September 2013 and consolidate the feedback of the GCC members. In attendance were 63 senior-level participants, from seven countries, representing 46 bioanalytical CRO companies/sites. This event represented a unique opportunity for CRO bioanalytical experts to share their opinions and concerns regarding the draft FDA Guidance, and to build unified comments to be provided to the FDA.
    Carisoprodol was authorised in 1959 without a full pharmacokinetic–pharmacodynamic (PK–PD) characterisation. We designed a crossover, double-blind, placebo-controlled, randomized clinical trial to characterize the PKs of carisoprodol and... more
    Carisoprodol was authorised in 1959 without a full pharmacokinetic–pharmacodynamic (PK–PD) characterisation. We designed a crossover, double-blind, placebo-controlled, randomized clinical trial to characterize the PKs of carisoprodol and its main active metabolite, meprobamate, after single (350 mg), multiple (350 mg/8 h, 14 days), and double (700 mg) doses of carisoprodol. Thirteen healthy volunteers were enrolled. After a single (350 mg) dose, the main carisoprodol parameters were (mean ± SD) Cmax: 2580 ± 1214 ng/mL, AUC0-∞: 8072 ± 6303 h x ng/mL, and half-life (T1/2): 2 ± 0.8 h. For meprobamate, the parameters were Cmax: 2181 ± 605 ng/mL and 34529 ± 7747 h x ng/mL y 9 ± 1.9 h. Different profiles were found for extensive and poor 2C19 metabolizers. After 14 days of treatment (350 mg/8 h) the results for carisoprodol were (mean ± SD) Cmax: 2504 ± 730 ng/mL, AUC0-∞: 7451 ± 3615 h x ng/mL, and T1/2: 2 ± 0.7 h. For meprobamate (a steady state was reached), the parameters were Cmax: 57...
    The cardiovascular and neuroendocrine effects and pharmacokinetics of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") were assessed in a double-blind, randomized, crossover, and controlled (placebo and amphetamine) clinical... more
    The cardiovascular and neuroendocrine effects and pharmacokinetics of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") were assessed in a double-blind, randomized, crossover, and controlled (placebo and amphetamine) clinical trial. Eight men with experience in the recreational use of MDMA participated in four 10-h experimental sessions with a 1-week washout period. Single oral doses of 125 mg and 75 mg of MDMA, 40 mg of amphetamine, and placebo were given. Both MDMA doses significantly increased blood pressure (increases of 40 mm Hg in systolic blood pressure), heart rate (increases of 30 beats/min), and pupillary diameter (mydriasis) as compared with placebo. Oral temperature did not show significant changes in any drug-active condition. Plasma cortisol levels showed a statistically significant increase after MDMA administration. Prolactin levels only increased after high dose of MDMA. Cmax values for 125-mg and 75-mg MDMA doses were 236.4 and 130.9 ng/ml, and Tmax was...
    A gas chromatographic method with nitrogen-phosphorus detection involving a solid-liquid extraction phase was developed and validated for the simultaneous quantification of 3,4-methylenedioxymethamphetamine (MDMA) and... more
    A gas chromatographic method with nitrogen-phosphorus detection involving a solid-liquid extraction phase was developed and validated for the simultaneous quantification of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in plasma. A modification of this method was validated for the analysis of MDMA, MDA, 4-hydroxy-3-methoxymethamphetamine (HMMA) and, 4-hydroxy-3-methoxyamphetamine (HMA) in urine. Under the analytical conditions described, the limits of detection in plasma and urine were less than 1.6 microg/l and 47 microg/l, respectively, for all the compounds studied. Good linearity was observed in the concentration range evaluated in plasma (5-400 microg/l) and urine (100-2000 microg/l) for all compounds tested. The recoveries obtained from plasma were 85.1% and 91.6% for MDMA and MDA, respectively. Urine recoveries were higher than 90% for MDMA and MDA, 74% for HMMA, and 64% for HMA. Methods have been successfully used in the assessment of plasma and urine concentrations of MDMA and its main metabolites in samples from clinical studies in healthy volunteers.
    An analytical method for the simultaneous determination of amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, and desmethylclomipramine in human plasma using promazine as internal standard is described. The method is... more
    An analytical method for the simultaneous determination of amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, and desmethylclomipramine in human plasma using promazine as internal standard is described. The method is based on a solid-phase extraction procedure using the Bond-Elut TCA columns followed by separation and detection using capillary gas chromatography with a specific nitrogen phosphorous detector (GC/NPD). Using the new extraction procedure, the problem of adsorption losses was overcome, and good recoveries were achieved for all compounds tested (>87%). Furthermore, clean extracts free of chromatographic interferences were obtained. Complete separation of underivatized, tricyclic antidepressant compounds was achieved in <11 minutes with reliable chromatographic performance. The limits of detection ranged from 1.2 to 5.8 microg/l. Calibration curves, showing good linearity, were prepared covering the therapeutic concentrations range expected (20 to 500 microg/l). The interassay precision values (RSD) ranged from 4.5% to 9.8%. It is concluded that extraction of amitriptyline, nortriptyline, imipramine, desipramine, clomipramine, and desmethylclomipramine, with Bond Elut TCA solid-phase columns followed by their detection using GC/NPD provides a sensitive and reproducible method that can be easily automated for immediate and routine analysis of clinical samples.
    Cocaethylene is an active metabolite produced when cocaine is consumed jointly with ethanol. The development of analytical techniques for determining cocaethylene and other cocaine metabolites is highly relevant for pharmacokinetic and... more
    Cocaethylene is an active metabolite produced when cocaine is consumed jointly with ethanol. The development of analytical techniques for determining cocaethylene and other cocaine metabolites is highly relevant for pharmacokinetic and toxicology studies of the cocaine and alcohol interaction in humans. The gas chromatography/mass spectrometry (GC/MS) method here reported is based on a single solid-phase extraction together with deuterated internal standards previously added to urine, followed by derivatization with pentafluoropropionic anhydride (hydroxyl and amine functions) and 1,1,1,3,3,3 hexafluor-2-propanol (carboxylic acid function) and injection into a capillary GC system coupled to a mass spectrometric detector in the selected ion monitoring acquisition mode. A sensitivity of 1-2 ng ml-1 for the quantitative analysis of cocaine and its main metabolites (ecgonine methyl ester, benzoylecgonine, cocaethylene and norcocaine) was achieved. In addition, some other minor metabolites were easily extracted and detected.
    A rapid, simple and sensitive method is described for the simultaneous determination in human plasma of the well known antiviral agent zidovudine (AZT) and its main metabolite, zidovudine-5'-O-glucuronide (G-AZT), using a... more
    A rapid, simple and sensitive method is described for the simultaneous determination in human plasma of the well known antiviral agent zidovudine (AZT) and its main metabolite, zidovudine-5'-O-glucuronide (G-AZT), using a solid-phase extraction method for sample preparation and a rapid ion-pair HPLC separation method with diode-array ultraviolet detection. The method overcomes the problems experienced in other procedures because of the large difference in polarity of the two compounds and the pH-sensitive retention of G-AZT by using n-octylamine to increase the retention of the glucuronide and improve the overall chromatographic behaviour. AZT and G-AZT are eluted at 3.6 and 5 min, respectively, with 7-ethyltheophylline used as internal standard eluting at 4.2 min. Caffeine, a good marker for the elution of related compounds present in plasma, appears well before, at 2.6 min. Quantification limits were established at 0.025 and 0.050 micrograms/ml for AZT and G-AZT, respectively. The improvement in method reproducibility due to the late elution of G-AZT could be observed even at the quantification limit at which an inter-assay relative standard deviation of only 6.4% was found after 3 months of routine use of the method.
    ... Jordi Ortuño a , Maria-Isabel Covas b , g , Magi Farre a , c , Mitona Pujadas a , g , Montserrat Fito b , g , Olha Khymenets a , g , Cristina Andres-Lacueva d , Pere Roset a , c , Jesús Joglar e , Rosa M. Lamuela-Raventós d and Rafael... more
    ... Jordi Ortuño a , Maria-Isabel Covas b , g , Magi Farre a , c , Mitona Pujadas a , g , Montserrat Fito b , g , Olha Khymenets a , g , Cristina Andres-Lacueva d , Pere Roset a , c , Jesús Joglar e , Rosa M. Lamuela-Raventós d and Rafael de la Torre a , f , g , Corresponding Author ...
    The involvement of mu-opioid receptors in the rewarding properties of MDMA was explored in mu-opioid receptor knockout mice using the conditioning place preference paradigm. The associated release of dopamine in the nucleus accumbens was... more
    The involvement of mu-opioid receptors in the rewarding properties of MDMA was explored in mu-opioid receptor knockout mice using the conditioning place preference paradigm. The associated release of dopamine in the nucleus accumbens was investigated by in vivo microdialysis. A significant rewarding effect of MDMA (10 mg/kg, i.p.) was observed in both wild-type and mu-opioid receptor knockout mice. MDMA (10 mg/kg, i.p.) also induced similar increases in dopamine and decreases in 3,4-dihydroxyphenylacetic acid and homovanillic acid in the nucleus accumbens dialysates of both wild-type and mu-opioid receptor knockout mice. No significant differences in basal levels of dopamine, 3,4-dihydroxyphenylacetic or homovanillic acids between wild-type and mu-opioid receptor knockout mice were observed. In summary, the present results suggest that, in contrast to what has been reported for other drugs of abuse such as opioids, ethanol, nicotine and Delta(9)-tetrahydrocannabinol, mu-opioid receptors do not play a major role in the rewarding properties of MDMA. These differences could be due to distinct mechanisms controlling dopamine release in the nucleus accumbens and suggest that the effects of MDMA on dopaminergic neurons are independent of micro -opioid receptors.
    These studies were conducted in order to assess the bioequivalence of two film-coated formulations containing 250 mg and 1000 mg of valacyclovir (INN: valaciclovir; CAS 124832-26-4), which is the L-valyl ester and a pro-drug of the... more
    These studies were conducted in order to assess the bioequivalence of two film-coated formulations containing 250 mg and 1000 mg of valacyclovir (INN: valaciclovir; CAS 124832-26-4), which is the L-valyl ester and a pro-drug of the antiviral drug acyclovir (INN: aciclovir). In the study with valacyclovir 250 mg, 36 healthy subjects were enrolled in a randomized, single-dose, open-label, 2-way crossover study, with a washout period of 10 days. In the study with valacyclovir 1000 mg, 46 healthy subjects were enrolled in a randomized, single-dose, open-label, 2-way crossover study, with a washout period of 7 days. Plasma samples were collected up to 36 h postdose for both studies. Valacyclovir levels were determined by liquid chromatography with tandem mass detection (ie, the LC/MS/MS method) (lower limit of quantification: 0.50 ng/ mL for valacyclovir and 9.93 ng/mL for acyclovir for the 250 mg study and 1.00 ng/mL for valacyclovir and 20.00 ng/ mL for acyclovir for the 1000 mg study). Pharmacokinetic parameters used for bioequivalence assessment were the area under the concentration-time curve from time zero to time of last non-zero concentration (AUC(0-t)) and from time zero to infinity (AUC(0-inf) and maximum observed concentration (C(max)). These parameters were determined from the valacyclovir concentration data using non-compartmental analysis. In the tained by analysis of variance (ANOVA) for valacyclovir were 107.54-124.26% for C(max), 95.45-103.46% for AUC(0-Inf) and 95.53-103.63% for AUC(0-t) whereas for acyclovir the 90% confidence intervals obtained were 103.19-117.02% for C(max), 99.61-106.92% for AUC(0-Inf) and 99.58-106.94% for AUC(0-t). In the study with valacyclovir 1000 mg formulations, the 90% confidence intervals obtained for valacyclovir were 93.20-107.35% for C(max), 90.87-96.27% for AUC(0-inf) and 90.87-96.27% for AUC(0-t) whereas for acyclovir the 90% CIs obtained were 95.98-104.94% for C(max), 97.13-103.94% for AUC(0-inf) and 97.14-104.09% for AUC(0-t). All the 90% confidence intervals obtained for all the parameters assessed were within the predefined range (80-125%). Based on these results, it can be concluded that the evaluated formulations are bioequivalent in terms of rate and extent of absorption.
    The study was conducted in order to compare the bioavailability of two tablet formulations containing letrozole 2.5 mg (CAS 112809-51-5). Twenty healthy subjects were enrolled in a single-centre, bioequivalence, randomised, single-dose,... more
    The study was conducted in order to compare the bioavailability of two tablet formulations containing letrozole 2.5 mg (CAS 112809-51-5). Twenty healthy subjects were enrolled in a single-centre, bioequivalence, randomised, single-dose, open-label, two-way crossover study, performed under fasting conditions with a minimum washout period of 21 days. Plasma samples were collected up to 240 h post-dosing. Letrozole levels were determined by reverse liquid chromatography and detected by tandem mass spectrometry detection, LC/MS/MS method. Pharmacokinetic parameters used for bioequivalence assessment, area under the concentration-time curve from time zero to time of last non-zero concentration (AUC(0-t)) and from time zero to infinitive (AUC(0-inf)) and maximum observed concentration (Cmax), were determined from the letrozole concentration data using non-compartmental analysis. The 90% confidence intervals obtained by analysis of variance were 90% geometric confidence Intervals of the ratio (A/B) of least-squares means from the analysis of variance (ANOVA) of the In-transformed AUC(0-t), and Cmax was within 80% to 125%. Bloequivalence between formulations was concluded both in terms of rate and extent of absorption.
    Background: Animal and in vitro studies suggest that phenolic compounds in virgin olive oil are effective antioxidants. In animal and in vitro studies, hydroxytyrosol and its metabolites have been shown to be strong antioxidants. One of... more
    Background: Animal and in vitro studies suggest that phenolic compounds in virgin olive oil are effective antioxidants. In animal and in vitro studies, hydroxytyrosol and its metabolites have been shown to be strong antioxidants. One of the prerequisites to assess their in vivo physiologic significance is to determine their presence in human plasma. Methods: We developed an analytical method for both hydroxytyrosol and 3-O-methyl-hydroxytyrosol in plasma. The administered dose of phenolic compounds was estimated from methanolic extracts of virgin olive oil after subjecting them to different hydrolytic treatments. Plasma and urine samples were collected from 0 to 12 h before and after 25 mL of virgin olive oil intake, a dose close to that used as daily intake in Mediterranean countries. Samples were analyzed by capillary gas chromatography–mass spectrometry before and after being subjected to acidic and enzymatic hydrolytic treatments. Results: Calibration curves were linear (r >0...
    3,4-Methylenedioxymethamphetamine (MDMA) is frequently consumed in association with alcohol. The effect of this combination in humans has not been previously investigated. Nine male healthy volunteers received single oral doses of 100 mg... more
    3,4-Methylenedioxymethamphetamine (MDMA) is frequently consumed in association with alcohol. The effect of this combination in humans has not been previously investigated. Nine male healthy volunteers received single oral doses of 100 mg of MDMA plus 0.8 g/kg ...
    The study was conducted in order to assess the bioequivalence of two film-coated formulations containing 100 mg of losartan (CAS 124750-99-8) and 12.5 mg of hydrochlorothiazide (CAS 58-93-5). Seventy-three healthy subjects were enrolled... more
    The study was conducted in order to assess the bioequivalence of two film-coated formulations containing 100 mg of losartan (CAS 124750-99-8) and 12.5 mg of hydrochlorothiazide (CAS 58-93-5). Seventy-three healthy subjects were enrolled in a randomised, single-dose, open-label, two-way crossover study, with a minimum washout period of 7 days. A total of 21 blood samples were collected up to 36 h post-dosing. Losartan, losartan carboxy acid and hydrochlorothiazide levels were determined by liquid chromatography with tandem mass detection (lower limit of quantification: 1.01 ng/mL for hydrochlorothiazide, 2.02 ng/mL for losartan and 2.51 ng/mL for losartan carboxy acid). Pharmacokinetic parameters used for bioequivalence assessment (AUC(0-t) and Cmax as primary and AUC(0-inf) as secondary pharmacokinetic parameters) were determined from the losartan and hydrochlorothiazide concentration data using non-compartmental analysis. Data from losartan carboxy acid was reported and presented a...
    Ayahuasca is a South American psychotropic beverage prepared from plants native to the Amazon River Basin. It combines the hallucinogenic agent and 5-HT(2A/2C) agonist N,N-dimethyltryptamine (DMT) with beta-carboline alkaloids showing... more
    Ayahuasca is a South American psychotropic beverage prepared from plants native to the Amazon River Basin. It combines the hallucinogenic agent and 5-HT(2A/2C) agonist N,N-dimethyltryptamine (DMT) with beta-carboline alkaloids showing monoamine oxidase-inhibiting properties. In the present paper, an analytical methodology for the plasma quantification of the four main alkaloids present in ayahuasca plus two major metabolites is described. DMT was extracted by liquid-liquid extraction with n-pentane and quantified by gas chromatography with nitrogen-phosphorus detection. Recovery was 74%, and precision and accuracy were better than 9.9%. The limit of quantification (LOQ) was 1.6 ng/ml. Harmine, harmaline, and tetrahydroharmine (THH), the three main beta-carbolines present in ayahuasca, and harmol and harmalol (O-demethylation metabolites of harmine and harmaline, respectively) were measured in plasma by means of high-performance liquid chromatography (HPLC) with fluorescence detectio...
    Background: Saliva is an alternative biologic matrix for drugs-of-abuse testing that offers the advantages of noninvasive, rapid, and easy sampling. We studied the excretion profile of 3,4-methylenedioxymethamphet- amine (MDMA) and its... more
    Background: Saliva is an alternative biologic matrix for drugs-of-abuse testing that offers the advantages of noninvasive, rapid, and easy sampling. We studied the excretion profile of 3,4-methylenedioxymethamphet- amine (MDMA) and its metabolites in both saliva and plasma, as well the effect of the drug on salivary pH. Methods: Saliva and plasma samples were obtained from eight healthy MDMA consumers after
    The study was conducted in order to assess the bioequivalence of two film-coated formulations containing 100 mg of losartan (CAS 124750-99-8) and 12.5 mg of hydrochlorothiazide (CAS 58-93-5). Seventy-three healthy subjects were enrolled... more
    The study was conducted in order to assess the bioequivalence of two film-coated formulations containing 100 mg of losartan (CAS 124750-99-8) and 12.5 mg of hydrochlorothiazide (CAS 58-93-5). Seventy-three healthy subjects were enrolled in a randomised, single-dose, open-label, two-way crossover study, with a minimum washout period of 7 days. A total of 21 blood samples were collected up to 36 h post-dosing. Losartan, losartan carboxy acid and hydrochlorothiazide levels were determined by liquid chromatography with tandem mass detection (lower limit of quantification: 1.01 ng/mL for hydrochlorothiazide, 2.02 ng/mL for losartan and 2.51 ng/mL for losartan carboxy acid). Pharmacokinetic parameters used for bioequivalence assessment (AUC(0-t) and Cmax as primary and AUC(0-inf) as secondary pharmacokinetic parameters) were determined from the losartan and hydrochlorothiazide concentration data using non-compartmental analysis. Data from losartan carboxy acid was reported and presented as supportive data. The 90% confidence intervals (obtained by ANOVA) for losartan were 97.05-118.48% for Cmax 100.76-106.10% for AUC(0-t) and 100.80-106.10% for AUC(0-inf) whereas for hydrochlorothiazide the 90% confidence intervals obtained were 103.94-115.33% for Cmax, 101.97-109.61% for AUC(0-t) and 101.77-109.02% for AUC(0-inf), and for losartan carboxy acid the intervals obtained were 98.31-107.82% for Cmax, 97.89-104.30% for AUC(0-t) and 98.06-104.30% for AUC(0-inf). All the 90% confidence intervals obtained for all the parameters assessed were within the predefined ranges (80-125%). Based on these results, it can be concluded that the evaluated formulations are bioequivalent in terms of rate and extent of absorption.