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  1. 1

    Avaliação pré-clínica do perfil farmacocinético do protótipo antitumoral lLQFM030 em ratos por LC-MS/MS

    Publicação
    por Zoghaib, Iury Valentim Jorge
    Origem: Oasisbr
    The LQFM030 was obtained by molecular simplification of nutlins (inhibitors of p53-MDM2 interaction) and, having demonstrated excellent antineoplastic activity in vitro (cytotoxicity against K-562 cell line with IC50 = 23 M) and in vivo against Ehrlich ascitic tumor with increased survival in treated animals developed the pharmacokinetic study of p.o. in rats. It was used for LC-MS/MS analytical method (Applied Biosystems MDS Sciex API 3200) previously validated together. O LQFM030 was administered to 3 rats (mean weight 186g) in predetermined dose of 100 mg/kg by gavage. After administration, samples were collected from 1.0 mL of blood by cannulation of the left jugular vein with heparinized syringe, the intervals 0-8 h. The blood samples were identified and centrifuged to obtain plasma which was frozen at -20°C until analysis. The kinetic parameters were calculated in the software WinNonlin 5.0 (Pharsight™). Results (mean ± SD) half-life (t1/2) 3.61 ± 0.68 h, total clearance (CLT) 36.49 ± 2.23 mL/min/kg, volume of distribution (Vd) 11,40 ± 1.58 L/kg. The LQFM030 had low value of t1/2, Vd high and high value of CLT. These values allow us to understand that the prototype study demonstrated a good safety profile of tissue distribution and/or has been extensively eliminated. When compared with the kinetic parameters obtained in other studies, it was observed difference in results is justified by the high interspecies variability, mainly in basal metabolic rate and body weight, once the route of administration, orally and intraperitoneally, are kinetically similar.
  2. 2

    Estudo do perfil cinético e alométrico do protótipo de fármaco antineoplásico LQFM018 em modelos experimentais por LC-MS/MS

    Publicação
    por Rodrigues, Andryne Rego
    Origem: Oasisbr
    LQFM018 is a prototype drug with proven anticancer activity in vitro (cytotoxicity against K-562 cell line, IC50 = 0.07652 mM), which was obtained by molecular simplification from antitumor compounds called nutlins, inhibitors of the interaction MDM2-p53. This study aimed to determine its pharmacokinetic profile, using, to this end, validated bioanalytical method in LC-MS/MS. The parameters used in analytical LC-MS/MS were: ACE® C18 column (100 mm × 4.6 mm, 5 μm), mobile phase buffer 2 mM ammonium acetate with 0.025% formic acid and methanol (50%:50% v/v), flow 1.2 mL/min, temperature of the column 40 °C, internal standard (IS) domperidone, liquid-liquid extraction with methyl tert-butyl ether (MTBE) and injection volume of 3.0 μL. The method was linear from 10 to 15,000 ng/mL (r = 0.9997). Intrarun precision was ranged from 0.6% to 5.5% and interrun from 1.8% to 6.7%. The accuracy found was 99.0% to 107.0% and the average recovery of controls was 74.1% ± 4.9%. The retention times were 3.16 min for LQFM018 and 1.81 min to domperidone. LQFM018 was administered to 3 females Wistar rats at 100 mg/kg, i.p. After administration, 0.5 mL samples of blood were collected by cannulation of the left jugular vein with heparinized syringe, at 1h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h and 9 h. Blood samples were identified and centrifuged to obtain plasma which was frozen at -20 °C until the time of analysis. The pharmacokinetic parameters (mean ± SD) were t½ = 2.89 ± 2.0 h; ClT/F = 22.01 ± 13.5 mL/min/kg; Vd/F = 5.48 ± 3.6 L/kg. The values of Vd/F, t½ and CLT/F extrapolated using allometric scaling for a person weighing 70 kg were 1954.3 L/kg, 12.6 h and 1800.4 mL/min/kg, respectively. The bioanalytical method was suitable for the detection and quantification of LQFM018 from plasma rat. The kinetic profile, extrapolated on allometric scaling, revealed a high value of t½, high Vd and long value of CLT, allowing understand that the studied prototype showed good tissue distribution profile and was extensively eliminated.
  3. 3

    Desenvolvimento e validação de técnica bioanalítica em LC-MS/MS para detecção e quantificação de protótipos antineoplásticos

    Publicação
    por Gomes, Sandro Antônio
    Origem: Oasisbr
    A rapid, sensitive and selective liquid chromatography tandem mass spectrometry (LC/MS-MS) bioanalytical method was developed and validated to quantify LQFM018 and LQFM030 prototypes obtained by molecular simplification nutlins (inhibitors of MDM2-p53 interaction) in mouse, rat and human plasma. The prototypes and the internal standard domperidone were extracted from the plasma samples by liquid-liquid extraction using methyl tert-butyl ether. The chromatographic analysis was performed using ACE ® C18 analytical column (5µm 100 x 4.6 mm) for a total time of 4 minutes. In MRM method transitions (m/z) were used: 349.138/191.10, 319.162/191.20 and 426.032/175.20 Daltons to LQFM018; LQFM030 and internal standard, respectively. The mobile phase consists of methanol-2 mM ammonium acetate containing 0.025% formic acid. The calibration curve was linear over the concentration range examined 10- 15000 ng/mL with r> 0.99 and the limit of quantitation of 10 ng/mL for both prototypes. For LQFM018, intra-assay precision was 0.8 to 7.3% and accuracy from 96.8 to 105.8%. And inter-assay to the precision was 2.3 and 6.6% and accuracy was 99.3 to 104.3%. The average recovery was 65.0% and the matrix effect between -11.2 to 2.1%. To LQFM030, intra-assay precision was 0.6 to 5.5% and accuracy from 95.5 to 111.3%. Inter-assay precision was 1.8 to 6.7%, and accuracy was 99.0 to 107.0%. The average recovery was 74.1% and the matrix effect from -7.9 to 1.5%. Recovery for internal standard was 61.3%. The prototypes were considered stable in the biological matrix and the solution proposed tests. Thus, the analytical method was developed and validated is capable to quantify traces of concentration in plasma.
  4. 4

    Guideline values and human risk assessment for the presence of anti-inflammatory drugs remaining in drinking water after lab scale treatment

    Publicação
    por Pais, Mariana Castello Novo
    Outros Autores: Nascimento, Elizabeth de Souza
    Origem: Oasisbr
    This study aimed to determine whether the anti-inflammatory drugs that are most commonly consumed in Brazil, including diclofenac, ketoprofen, naproxen, indomethacin, ibuprofen and acetaminophen, are present in drinking water and to derive guideline values to characterize the human risk. These pharmaceuticals were quantified in surface waters by LC-MS/MS with solid phase extraction, both before and after conventional treatment on a laboratory scale, using a jar test assay. The methods used to quantify these drugs showed good results: the chromatographic analysis obtained correlation coefficients between 0.9952 and 0.9991, with limits of quantification of 0.5 ng.mL-1 - 50 ng.mL-1 and precision standard deviations (0.08 - 2.08). Only ketoprofen and ibuprofen were not completely removed through the jar test. Environmental samples were collected and handled by the same method; the values ‌for ketoprofen and ibuprofen after treatment were 18.67 - 19.65 ng.L-1 (±17%) and 166.70 - 244.73 ng.L-1 (±14%), respectively. Human risk was assessed by comparing the guideline values for each compound to the concentrations obtained in the environmental samples, considering the toxicological backgrounds, following WHO (2011) method. The results suggest that the concentrations of ketoprofen and ibuprofen found in drinking water do not pose a risk to human health, even with chronic consumption.
    2018 artigo Brasil
  5. 5

    Simultaneous determination of candesartan and hydrochlorothiazide in human plasma by LC-MS/MS

    Publicação
    por Bonthu, Mohan Gandhi
    Outros Autores: Atmakuri, Lakshmana Rao; Jangala, Venkateswara Rao
    Origem: Oasisbr
    A simple, sensitive, rapid and highly efficient LC-MS/MS method was developed for the determination of Candesartan and Hydrochlorothiazide simultaneously in human plasma. The method employed Zorbax eclipse C18 (150 X 4.6 mm, 5µ) column using acetate buffer: acetonitrile (25:75%, v/v) as the mobile phase. The mobile phase flow rate is 1 mL/min which was delivered into the mass spectrometer electron spray ionization chamber. The Liquid/liquid extraction procedure was used in the method for the extraction of analytes. The chromatograph was attached to a negative ion mode tandem mass spectrometer and the method was validated for all the parameters as per the guidelines of US-FDA. The ions were detected in multiple reaction monitoring mode and the transitions are m/z 439.00®309.10 and 295.80®268.80 for candesartan and hydrochlorothiazide respectively. Isotopic standards were used as internal standards for effective recovery of the analytes. The drugs were analyzed over a calibration range of 1.027-302.047 ng/mL for candesartan and 1.044-306.945 ng/mL for hydrochlorothiazide respectively with regression coefficient greater than 0.99. The mean extraction recoveries are 96.95±5.61 and 100.55±4.82 for candesartan and hydrochlorothiazide respectively. The precision and accuracy values for all the studies were within the range of ≤15% and 85-115%. The performed stability studies indicate that the developed method is stable in plasma for 15 h at room temperature (bench top); 52 h (in injector); for 112 days at -70 ºC for long term stability; five successive freeze and thaw cycles. The developed method could be successfully employed for the determination of selected drugs in biological samples.
    2018 artigo Brasil
  6. 6

    Evaluation of the stability of Polymyxin B in saline and glucose solutions using LC-MS/MS

    Publicação
    por Castilhos, Juliana Kich
    Outros Autores: Dillenburg, Thaís Luise; Antunes, Marina Venzon; Scribel, Letícia; Zavascki, Alexandre Prehn; Linden, Rafael et al.
    Origem: Oasisbr
    Polymyxins are a group of antibacterial substances and have remained the drugs of choice for treatment of resistant Gram-negative bacilli. Polymyxin B is administered by intravenous infusion and requires the reconstitution of lyophilized powder with 0.9% saline or 5% glucose solutions. To date, there is little information about polymyxin stability in different infusions solutions, especially at 40 ºC, a temperature that is recommended to study drug stability as it accelerates degradation reactions. Therefore, in this work an analytical method using LC-MS/MS was developed, validated and applied to determine the stability of polymyxin B diluted in 0.9% saline or 5% glucose solutions at 25 ºC and 40 ºC. The stability of polymyxin B solutions was evaluated during 72 hours. Polymyxin B1 and B2 were stable for 24 hours in saline (0.9%) and glucose solution (5%), however a significant degradation of polymyxin B1 and B2 was observed after 48 hours and 72 hours of assay. The reduction of polymyxin content was evidenced in both saline and glucose media, at room temperature as well as at 40 °C. No significant differences in pH of polymyxin solutions (glucose or saline) were evidenced during stability assay.
    2020 artigo Brasil
  7. 7

    Pharmacokinetics and pharmacodynamics of Astragali Radix-Corni Fructus Herb-pair Extract, in kidney-yin deficiency model

    Publicação
    por Chu, Zixuan
    Outros Autores: Lu, Min; Liu, Teng; Xiong, Shan; Mu, Yanling
    Origem: Oasisbr
    To investigate the pharmacokinetics and pharmacodynamics of Astragali Radix-Corni Fructus herb-pair in kidney-yin deficiency model, which was made by continuously oral gavage of thyroxine. A simple and rapid LC-MS/MS method was developed and validated for the determination of loganin and morroniside in rat plasma and used for the pharmacokinetics study. The kidney-yin deficiency significantly changed the AUC(0-∞), Cmax and CLz/F of loganin and morroniside. The T1/2z of morroniside increased significantly in the kidney-yin deficiency rats. For the pharmacodynamics study, the liver index, kidney index, and ALT, TBIL, UREA, CREA level in the kidney-yin deficiency mice were examined. The herb-pair had been proved to be effective for the treatment of kidney-yin deficiency by affecting the liver, kidney, ALT, UREA and CREA, which showed positively correlated with the dose. The pharmacokinetics and pharmacodynamics studies in the pathological status could offer more valuable information for the future application of Astragali Radix-Corni Fructus herb-pair.
    2023 artigo Brasil
  8. 8

    Metabolomics approaches for the understanding of psychotic mental disorders

    Publicação
    por Lopes, Ana Olga Ventura Gomes Caiola
    Mental illnesses such as Schizophrenia (SCZ) and Bipolar Disorder (BD) can cause major disturbances in the cognitive and emotional control of their patients, which has a great impact on their lives. SCZ and BD are diseases that are difficult to diagnose due to the number of symptoms that overlap between them. Through the study of omics, it is possible not only to better understand these diseases, but also to study possible biomarkers, which could be extremely important to define a diagnosis, and consequently, provide a better treatment and prognosis for these patients. The Liquid Chromatography coupled to Mass Spectrometry (LC-MS) approach was used to study the metabolomics and peptidomics of 69 patients and 15 controls. Two comparisons were analyzed: Controls vs Disease and SCZ/Schizophreniform (SCZFM) vs BD/intermediate diagnosis. From the first comparison, it was possible to detect 4 interesting “features”, 7 endogenous metabolites and 11 statistically altered peptides. The interesting features were 452.7/11.8, 497.2/14.9, 516.3/24.5 and 757.4/8.3. The 7 interesting metabolites were Isoleucine/Leucine, N-Acetylalanine, Ornithine, Palmitoylcarnitine, Phenylalanine, Proline and Valine. Of the 11 peptides, there are 3 from the Fibrinogen Alpha Chain, 2 from the Apolipoprotein A-II protein, 2 from the Complement protein C4-B, 1 from the Complement protein C3, 1 from the Fibrinogen Beta Chain, 1 from the Kininogen-1 and 1 of the Selenocysteine- Specific Elongation Factor. In the second comparison, 4 statistically altered “features” were detected, 377.1/15.6, 448.3/21.9, 452.3/24.8 and 564.2/15.9. In addition to the individual molecules, in the first comparison 3 altered pathways were detected, Bile Acid Biosynthesis, Vitamin E Metabolism and Aminoacyl-tRNA Biosynthesis and in the second comparison no altered pathway was detected as altered. Although it was not possible to propose a potential biomarker or altered pathways that confidently distinguish SCZ from BD, we present the metabolic pathways on which future studies should focus on these two diseases for the improvement of the treatment.
    2022 dissertação de mestrado Portugal acesso aberto
  9. 9

    Development and validation of a LC-MS/MS method for determination of eight PEth homologues in whole blood

    Publicação
    por Maria, Marisa Henriques
    Phosphatidylethanol (PEth) is a group of direct ethanol biomarkers used to distinguish between different drinking patterns, such as heavy and social drinkers. So far, the PEth homologue most used for this purpose is PEth 16:0/18:1. This homologue is also the one determined in most of the LC-MS/MS methods developed for PEth analysis. Often one or a few PEth homologues are quantified in LC-MS/MS methods published, but recently a LC-MS/MS method for the determination of six PEth homologues was developed. The main aim of the dissertation was to develop a LC-MS/MS method for the quantitative determination of eight of the most common PEth homologues in whole blood. This can be helpful, especially for the determination of PEth in blood from people with high alcohol consumption. Chromatographic separation of the PEth homologues was tested on five UHPLC columns. Different mobile phases were investigated to optimize separation. Best chromatographic separation of the PEth homologues was achieved using an Acquity BEH C18 column (100 2.1 mm I.D., 1.7 µm particles) and a mobile phase consisting of 5 mM ammonium acetate pH 5 (Solvent A) and methanol (Solvent B). The total run time was 5.7 minutes. MS/MS parameters were optimized for each of the eight PEth homologues and internal standards. Two MRM transitions ions, those with the highest responses, were chosen for each compound. Isotope labeled internal standards were used for five of the eight PEth homologues. Two sample preparation techniques, liquid-liquid extraction (LLE) and 96-well supported liquid extraction (SLE), were investigated to extract the PEth homologues from blood. The extraction recoveries obtained were within 45-82% when LLE was used and within 68-80% when 96-well SLE was used. Matrix effects were studied and showed ion suppression for the majority of the PEth homologues, and ion enhancement for PEth 17:0/18:1. For compounds with their own internal standards, the matrix effects were corrected for their internal standard. An LC-MS/MS method for the determination of eight PEth homologues was developed and validated. The validation showed that UHPLC-MS/MS method is precise, accurate, and sensitive for its purposes.
    2022 dissertação de mestrado Portugal acesso aberto
  10. 10

    An accurate and precise liquid chromatography–tandem mass spectrometry method for the determination of six phosphatidylethanol homologues in whole blood with phospholipid interfere...

    Publicação
    por Maria, Marisa
    Outros Autores: Neng, Nuno R.; Berg, Thomas
    Alcohol consumption is associated with a wide risk of different diseases, injury and death, and has significant social and economic consequences worldwide. Phosphatidylethanol (PEth) is a group of promising direct alcohol biomarkers, with a significantly longer half-life in blood than ethanol, which can be measured to predict different drinking patterns, such as heavy- and social drinking. This study aimed to develop and validate an accurate and precise LC-MS/MS method for the determination of six PEth homologues in whole blood with minimal interference from unwanted phospholipids. Different organic solvent mixtures for liquid-liquid extraction were investigated to obtain satisfactory recovery of PEth homologues and removal of the lyso-phospholipids and other early eluting phospholipids. The mixture of heptane/2-propanol (80:20, v:v) gave lower phospholipid background and better signal/noise values for the PEth peaks. An LC-MS/MS TQ-S system from Waters was used for the instrumental analysis. The main part of unwanted phospholipids were separated from the PEth homologues on an Acquity BEH C18 column (50 × 2.1 mm ID, 1.7 µm particles) using a buffer-free mobile phase of 0.025 % ammonia in Type 1 water, pH 10.7, as solvent A and methanol as solvent B. Validation and quantification of 22 authentic blood samples showed that the developed LC-MS/MS method is sensitive, precise and accurate for the determination of the six PEth homologues in whole blood. Lower limit of quantification was 10 nM for all compounds. No matrix effects were observed, possibly due to the successful strategies incorporated to avoid the influence of unwanted phospholipids.
    2023 contribuição para revista Portugal acesso aberto