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1.
Inflammopharmacology ; 31(5): 2451-2465, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37667090

RESUMO

In the scope of a research program with the goal of developing treatments for inflammatory diseases, the pharmacological evaluation of LQFM291, designed by molecular hybridization from butylated hydroxytoluene and paracetamol, was described. The antioxidant profile of LQFM291 was evaluated by electrochemical measurement. Also, acute or repeated treatments with equimolar doses to paracetamol were used to evaluate the antinociceptive and/or anti-inflammatory activities of LQFM291 in animal models. The toxicologic potential of LQFM291 was also evaluated and compared to paracetamol through biochemical and histopathological analysis after the repeated treatment schedule. As a result of the acute treatment, paracetamol showed a similar antinociceptive effect in formalin test compared to LQFM291. Whereas, after the repeated treatment, when carrageenan-induced hyperalgesia and edema tests were performed, paracetamol showed a delayed antinociceptive and anti-inflammatory effect compared to LQFM291. Furthermore, as other advantages the LQFM291 showed a high redox capacity, a gastroprotective activity and a safety pharmacological profile without any liver or kidney damage. These effects can be related to the prevention of oxidative stress by reduction of protein and lipid peroxidation in gastric tissue, maintenance of glutathione levels in hepatic homogenate, and a systemic reduction of pro-inflammatory cytokine levels, which may characterize the LQFM291 as a more viable and effective alternative to relief pain and inflammatory signs in patients with chronic disorders.


Assuntos
Acetaminofen , Anti-Inflamatórios , Animais , Humanos , Acetaminofen/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Dor/tratamento farmacológico , Carragenina , Extratos Vegetais/farmacologia , Analgésicos/efeitos adversos , Edema/induzido quimicamente , Edema/tratamento farmacológico
2.
Life Sci ; 312: 121199, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36402170

RESUMO

AIMS: Oxidative stress, impaired antioxidant defense and neuroinflammation are often associated with the onset and progression of neuropsychiatric diseases. Conversely, several piperazine compounds presents beneficial neuropharmacological effects as well as antioxidant activity, and some derivatives combine both activities. LQFM212 (2,6-di-tert-butyl-4-((4-(2-hydroxyethyl)piperazin-1-yl)methyl)phenol) was synthesized to produce effects on CNS and to have an additional antioxidant effect. Previous preclinical tests have been shown anxiolytic- and antidepressant-like effects of LQFM212 in mice. Herein, the main objective was to verify the possible antioxidant potential and the effects of LQFM212 against behavioral changes, inflammatory and oxidative markers induced by lipopolysaccharide (LPS). MAIN METHODS: Initially, antioxidant potential of LQFM212 was evaluated by electrochemical assays. Afterwards, the effects of oral treatment with LQFM212 were evaluated in mice using LPS-induced models of systemic or local inflammation. KEY FINDINGS: In LPS-induced neuroinflammation, LQFM212 treatment reverted changes caused by LPS, demonstrated by attenuated anxiogenic- and depressive-like behaviors, reduced pro-inflammatory cytokines (TNF-α and IL-1ß) and increased anti-inflammatory cytokines (IL-4 and IL-10) on serum, and also improved oxidative stress-related changes (levels of nitrite, malondialdehyde, glutathione and carbonylated protein, and superoxide dismutase, catalase, myeloperoxidase and cholinesterase activities) on brain cortex and hippocampus. However, LQFM212 treatment did not attenuate the inflammatory changes in LPS-induced pleurisy model. SIGNIFICANCE: LQFM212 presents antioxidant activity and ameliorates behavioral, inflammatory and oxidative changes after LPS-induced neuroinflammation model. These effects do not seem to be secondary to a peripheral anti-inflammatory action of LQFM212, since this compound failed to attenuate the inflammatory changes in LPS-induced pleurisy model.


Assuntos
Lipopolissacarídeos , Pleurisia , Camundongos , Animais , Lipopolissacarídeos/farmacologia , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Doenças Neuroinflamatórias , Estresse Oxidativo , Citocinas/metabolismo
3.
Behav Brain Res ; 417: 113582, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-34536431

RESUMO

The current treatments available for anxiety and depression are only palliative. Full remission has remained elusive, characterizing unmet medical needs. In the scope of an academic drug discovery program, we describe here the design, synthesis, in vitro metabolism prediction and pharmacological characterization of a new piperazine compound, 1-(4-methoxyphenyl)-4-((1-phenyl-1H-pyrazol-4-yl)methyl)piperazine (LQFM005), and of its main putative metabolite, 4-(4-((4-(4-methoxyphenyl)piperazin-1-yl)methyl)- 1H-pyrazol-1-yl)phenol (LQFM235). The production of the metabolite was initially performed by in vitro biotransformation of LQFM005 using Aspergillus candidus and then by chemical synthesis. Oral administration of either 12 or 24 µmol/kg LQFM005 to mice did not affect spontaneous locomotor activity but increased the time spent in the center of the open field. Both LQFM005 and LQFM235 (24 µmol/kg) increased the time spent by the mice in the open arms of the elevated plus maze (EPM), a good indication of anxiolytic-like effect, and decreased the immobility time in the forced swimming test (FST), suggesting an antidepressant-like effect. The previous administration of WAY-100635 (a 5-HT1A antagonist) abolished the effects of LQFM005 in both EPM and FST. Binding experiments showed that LQFM005 and its metabolite bind to the 5-HT1A receptor with a moderate affinity (Ki around 5-9 µM). The two compounds are relatively safe, as indicated by cytotoxic assessment using the 3T3 fibroblast cell line and estimated LD50 around 600 mg/kg. In conclusion, oral administration of the newly synthesized phenylpiperazines produced anxiolytic- and antidepressant-like effects in behavioral tests, putatively in part through the activation of 5-HT1A receptors.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Ansiedade/tratamento farmacológico , Depressão/tratamento farmacológico , Piperazinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Locomoção , Masculino , Camundongos , Piperazinas/antagonistas & inibidores , Piperazinas/metabolismo , Piridinas/antagonistas & inibidores , Natação
4.
Molecules ; 26(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34946705

RESUMO

The binding between anticancer drugs and double-stranded DNA (dsDNA) is a key issue to understand their mechanism of action, and many chemical methods have been explored on this task. Molecular docking techniques successfully predict the affinity of small molecules into the DNA binding sites. In turn, various DNA-targeted drugs are electroactive; in this regard, their electrochemical behavior may change according to the nature and strength of interaction with DNA. A carbon paste electrode (CPE) modified with calf thymus ds-DNA (CPDE) and computational methods were used to evaluate the drug-DNA intercalation of doxorubicin (DOX), daunorubicin (DAU), idarubicin (IDA), dacarbazine (DAR), mitoxantrone (MIT), and methotrexate (MTX), aiming to evaluate eventual correlations. CPE and CPDE were immersed in pH 7 0.1 mM solutions of each drug with different incubation times. As expected, the CPDE response for all DNA-targeted drugs was higher than that of CPE, evidencing the drug-DNA interaction. A peak current increase of up to 10-fold was observed; the lowest increase was seen for MTX, and the highest increase for MIT. Although this increase in the sensitivity is certainly tied to preconcentration effects of DNA, the data did not agree entirely with docking studies, evidencing the participation of other factors, such as viscosity, interfacial electrostatic interactions, and coefficient of diffusion.


Assuntos
Antineoplásicos/química , DNA/química , Substâncias Intercalantes/química , Simulação de Acoplamento Molecular
5.
Adv Pharm Bull ; 11(3): 469-476, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34513621

RESUMO

Purpose: The development biosensing technologies capable of delivering fast and reliable analysis is a growing trend in drug quality control. Considering the emerging use of plant-based polyphenol oxidases (PPO) as biological component of electrochemical biosensors, this work reports the first Solanum lycocarpum PPO biosensor and its use in the pharmaceutical analysis of paracetamol in tablet formulations. Methods: The biosensor was optimized regarding fruit maturation (immature and mature-ripe), vegetal extract volume to be used in biosensor construction as well as optimal pH of electrochemical cell fluid. Results: Results evidenced that the extract which rendered the biosensor with best analytical performance was from immature fruits, and the biosensor produced using 100 µL of crude plant extract promoted better faradaic signal gathering. Moreover, when neutral pH media was used in the electrochemical cell, the biosensor showcased best faradaic signal output from the used redox probe (catechol), suggesting thence that the method presents high sensibility for phenolic compounds detection. Furthermore, the biosensor was able to quantify paracetamol in a linear range from 50 to 300 µM, showcasing LoD and LoQ of 3 µM and 10 µM, respectively. Conclusion: after careful evaluation, this biosensor might be a low-cost alternative for conventional pharmaceutical quality control methods.

6.
Biosens Bioelectron ; 185: 113234, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33945892

RESUMO

This study presents a new polymeric and multielectronic system, the poly-Alizarin Red S (PARS), obtained from the electropolymerization of Alizarin Red S (ARS) dye on an edge-plane pyrolytic graphite electrode (EPPGE) surface. During EPPGE/PARS electrochemical characterization, we identified seven stable and reversible redox peaks in acidic medium (0.10 mol L-1, pH 1.62 KH2PO4), which indicated its mechanisms underlying electropolymerization and electrochemical behavior. To the best of our knowledge, this is the first study to use an EPPGE/PARS electrode to detect oxandrolone (OXA) in artificial urine, where PARS acts as a synthetic receptor for OXA. The interactions of OXA with EPPGE/PARS as well as the properties of PARS were investigated using density functional theory (DFT). Atomic force microscopy (AFM) was used to characterize EPPGE/PARS, and it was found that the PARS polymer formed a semi-globular phase on the EPPGE surface. The limit of detection for OXA found by the sensor was close to 0.50 nmol L-1, with a recovery rate of approximately 100% in artificial urine. In addition to the application proposed in this study, EPPGE/PARS is a low-cost product that could be applied in several devices and processes, such as supercapacitors and electrocatalysis.


Assuntos
Técnicas Biossensoriais , Grafite , Antraquinonas , Eletrodos , Eletrônica , Oxandrolona
8.
Braz. J. Pharm. Sci. (Online) ; 57: e18989, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345450

RESUMO

Hospital infections (HI) are a serious public health problem in many countries. Several studies have identified strains correlating to surgical site infections, many with multi-resistance. The goals of this study was to quantify, to identify and to verify the resistance profile of microorganisms collected at two hospitals settings, and to alert health professionals how environmental contamination can influence hospital infection rates. For air sampling in operating rooms, intensive care unit and materials sterilization center, the impaction method (Spin Air, IUL®) and passive sedimentation were used. For the isolation of bacteria on surfaces and uniforms contact plates (RODAC®) were used. Identification of the microorganisms was performed using Vitek® 2 Systems. The antibiograms were conducted according to the disk diffusion method recommended by CLSI. The surgical center of hospital B presented more than 500 CFU/m3 in aerial microbial load. In the aerial microbiota of the sampled areas of both hospitals, M. luteus, S. haemolyticus and S. hominis spp hominis were the prevalent microorganisms, with a percentage greater than 30%. On the surfaces and uniforms there was a prevalence of M. luteus (40%) and S. hominis spp hominis (20%) among others, and some of the resistant strains were isolated from environments with microbial load within the recommended limits.


Assuntos
Hospitais/normas , Imperícia/classificação , Resistência a Medicamentos , Monitoramento Ambiental/instrumentação , Infecção Hospitalar/complicações , Pessoal de Saúde/educação , Poluição Ambiental/efeitos adversos
9.
J Am Soc Mass Spectrom ; 31(11): 2250-2257, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-32930580

RESUMO

A new approach using paper spray ionization mass spectrometry (PSI-MS) for the analysis of steroid hormones in wastewater samples has been demonstrated. Triangular papers containing paraffin barriers as microfluidic channels were used to direct the sample solution to the paper tip, preventing the sample from spreading over the corners of the paper. The method was used to analyze the hormones levonorgestrel and algestone acetophenide in industrial wastewaters. Analytical curves presented a correlation coefficient (R2) above 0.99. Limits of quantification were below 2.3 ppm and limits of detection below 0.7 ppm. Values of precision (coefficient of variation) and accuracy (relative error) were less than 15% for all analyses. Recovery results ranged from 82% to 102%. Levonorgestrel was also analyzed by high-performance liquid chromatography coupled to mass spectrometry in order to compare the analytical performance with PSI-MS. No statistically significant differences were found between both methods. This study demonstrates the usefulness of PSI-MS for rapid analysis of hormones in industrial wastewater samples and also indicates its potential to be employed as a simple and reliable analytical method in environmental sciences.


Assuntos
Hormônios/análise , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Esteroides/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Levanogestrel/análise , Limite de Detecção , Papel
10.
Pharmaceuticals (Basel) ; 13(4)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316568

RESUMO

Carvedilol (CRV) is a non-selective blocker of α and ß adrenergic receptors, which has been extensively used for the treatment of hypertension and congestive heart failure. Owing to its poor biopharmaceutical properties, CRV has been incorporated into different types of drug delivery systems and this necessitates the importance of investigating their compatibility and stability. In this sense, we have investigated the applicability of several electroanalytical tools to assess CRV compatibility with lipid excipients. Voltammetric and electrochemical impedance spectroscopy techniques were used to evaluate the redox behavior of CRV and lipid excipients. Results showed that Plurol® isostearic, liquid excipient, and stearic acid presented the greatest anode peak potential variation, and these were considered suitable excipients for CRV formulation. CRV showed the highest stability at room temperature and at 50 °C when mixed with stearic acid (7% w/w). The results also provided evidence that electrochemical methods might be feasible to complement standard stability/compatibility studies related to redox reactions.

11.
Med Mycol ; 58(7): 881-886, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32022862

RESUMO

The hospital environment requires special attention to air quality, since it needs to be healthy for the protection of patients and health professionals in order to prevent them against hospital infections. The objective of this study was to isolate, identify and evaluate the susceptibility profile of isolated fungi from two hospitals. For air sampling the impaction (Spin Air, IUL®) and passive sedimentation methods were used. For the isolation of fungi from surfaces, contact plates (RODAC®) were used. The identification of the fungi was performed by observing the macroscopic and microscopic aspects of the colonies, whereas for better visualization of fruiting structures, the microculture technique was performed on slides. To evaluate the susceptibility profile, the broth microdilution test recommended by CLSI was performed. Thirty-five isolates were identified: Aspergillus flavus (12), Aspergillus fumigatus (11), Aspergillus niger (1), Aspergillus terreus (2), Penicillium spp. (7), and Fusarium spp. (2) in the hospitals evaluated. All isolates had a minimum inhibitory concentration (MIC) more than 128 µg/ml for fluconazole; 0.5 to 4.0 µg/ml for amphotericin B (hospital 1), and all isolates from haospital 2 had MIC ≥2.0 µg/ml. In hospital 1, MIC for posaconazole ranged from 0.25 µg/ml to ≥32 µg/ml, and hospital 2 ranged from 0.5 to 1.0 µg/ml. The monitoring and evaluation of air quality and surfaces are essential measures for prevention and control of hospital infections, as these microorganisms are becoming increasingly resistant to antimicrobial agents, thus making treatment difficult, especially in immunocompromised individuals.


Assuntos
Antifúngicos/administração & dosagem , Aspergillus/isolamento & purificação , Equipamentos Médicos Duráveis/microbiologia , Fusarium/isolamento & purificação , Doença Iatrogênica/prevenção & controle , Penicillium/isolamento & purificação , Esterilização/métodos , Humanos , Unidades de Terapia Intensiva , Salas Cirúrgicas , Estudos Prospectivos , Sala de Recuperação , Medição de Risco
12.
Braz. J. Pharm. Sci. (Online) ; 56: e17344, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1089212

RESUMO

Piroxicam (PRX) was determined in pharmaceutical capsules with differential pulse voltammetry (DPV) in a three electrode system consisting of a pencil graphite electrode (PGE) as working electrode, a Pt wire and a reference electrode of Ag/AgCl/KCl 3 M. An irreversible oxidation peak was observed in Epa c.a. 0.6 V, which correlates to the oxidation of PRX. The coefficient of linear correlation obtained was 0.9946, with limit of detection of 2.1 µM and limit of quantification of 4.7 µM. PGE assays showed good analytical performance compared to high performance liquid chromatography and spectrophotometry, showing the potential to be further developed and employed in quick and simple analyses.

13.
Adv Pharm Bull ; 9(3): 416-422, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31592074

RESUMO

Purpose: Jenipapo fruit (Genipa americana L) is a natural source of polyphenol oxidases (PPOs) whose potential in pharmaceutical analysis is noteworthy. Henceforth, this work reports the electrochemical study of a low-cost PPO-based biosensor produced from the crude extract of Jenipapo fruits and accounts a practical approach to employ this biosensor in the determination of methyldopa and paracetamol in pharmaceutical samples. Methods: In order to investigate the electrochemical properties of the biosensor, theoretical and practical approaches were employed, and both samples and the biosensor were analyzed through electrochemical impedance spectroscopy (EIS) and voltammetric techniques, namely: differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Results: showcased that the biosensor presented good analytical features, as well as low detection limits (8 µmol L-1 for methyldopa and 5 µmol L-1 for paracetamol). The relative standard deviation was less than 5% mid-assay. Conclusion: The use of this biosensor is a reliable, low cost and useful alternative in the pharmaceutic determination of phenolic drugs (e.g. methyldopa and paracetamol).

14.
Rev. bras. farmacogn ; 28(6): 678-685, Nov.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-977754

RESUMO

ABSTRACT Caryocar brasiliense Cambess., Caryocaraceae (pequi) is a typical Brazilian Cerrado tree. A previous study showed that the butanolic fraction of pequi leaves promotes endothelium-dependent relaxation mediated by nitric oxide and that it causes reversible hypotension in rats. In the present study, we investigated the cell signaling pathways associated with the butanolic fraction-induced nitric oxide release, and we characterized the chemical composition of its fraction. Vascular reactivity tests, a western blotting analysis, and a chemiluminescence assay were used to investigate the signaling pathways involved in the vasorelaxant effect of the butanolic fraction. Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry was used to characterize the butanolic fraction chemical composition. Vasorelaxation was mediated through the activation of the calmodulin and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways, leading to subsequent endothelial nitric oxide synthase phosphorylation and nitric oxide production, as evidenced by western blotting and chemiluminescence assays, respectively. The chemical characterization of the butanolic fraction revealed the presence of 72 oxygenated compounds, whose molecular formulae are compatible with phenolic compounds, suggesting a potential contribution of these compounds for the butanolic fraction vasorelaxant effect. These findings show that the calmodulin and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways are involved in the butanolic fraction-induced endothelial nitric oxide synthase activation and are promoted by polyphenol compounds present in the C. brasiliense leaves.

15.
Prep Biochem Biotechnol ; 48(6): 541-548, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29939831

RESUMO

Bioremediation is a strategy to mitigate environmental impacts of hazardous pollutants from anthropogenic sources. Natural byproducts, including agroindustrial wastes (AW) can be used to induce enzyme biosynthesis, leading up to enhancement of pollutants degradation process. Therefore, this study aimed to evaluate the use of cupuaçu, Theobroma grandiflorum AW as Pycnoporus sanguineus Laccase (Lac) inducer in order to promote 17-α-ethinylestradiol (EE2) bioremediation. The macro and micro-nutrients levels of cupuaçu AWs were evaluated in order to establish further correlations with enzymatic biosynthesis induction. The fungus was cultivated for 7 days in temperature of 28 ± 2 °C and agitation of 150 rpm. For bioremediation, Lac enzymatic extract was added to EE2 solution (10 µg mL-1) and the percentage of removal was evaluated by HPLC after 1-24 hr of reaction. At optimized conditions, the enzyme extract production was remarkably enhanced by adding only 1% (w/v) of cupuaçu AW. Lac activity reached 1642 U mL-1 on the 6th day of culture, which was higher than positive control (511 U mL-1). 86% of EE2 removal was reached after 4 hr, and after 8 hr of reaction, 96.5% was removed. Analysis by direct infusion in MS-ESI-TOF exhibited intermediary compounds formed by radical hydroxilation.


Assuntos
Biodegradação Ambiental , Cacau/metabolismo , Poluentes Ambientais/metabolismo , Etinilestradiol/metabolismo , Lacase/biossíntese , Pycnoporus/enzimologia , Meios de Cultura/química , Indução Enzimática , Proteínas Fúngicas/análise , Eletroforese em Gel de Poliacrilamida Nativa , Açúcares/análise , Temperatura
16.
Rev. bras. farmacogn ; 28(3): 325-332, May-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-958874

RESUMO

ABSTRACT The prevention of chronic and degenerative diseases, is a health concern deeply associated with oxidative stress. Such progressive phenomena can be avoided through exogenous antioxidant intake, which set up a reductant cascade, mopping up damaging free radicals. Medicinal herbs are commonly associated with high antioxidant potential, and hence their health benefits. The commerce of dried herbal extracts movements a big portion of developing countries economy. The determination of medicinal herbs the antioxidant activity capacity is of utmost importance. The assessment of antioxidant activity in phytotherapics is mostly achieved by spectrophotometric assays, however colored substances can produce interferences that do not occur in electroanalytical methods. Therefore, the aim of this paper is to compare spectrophotometric and voltammetric techniques to evaluate antioxidant activity in herbal drugs such as: Ginkgo biloba L., Camellia sinensis (L.) Kuntze, Theaceae; Hypericum perforatum L., Hypericaceae; Aesculus hippocastanum L., Sapindaceae; Rosmarinus officinalis L., Lamiaceae; Morinda citrifolia L., Rubiaceae; Centella asiatica (L.) Urb., Apiaceae; Trifolium pratense L., Fabaceae; Crataegus oxyacantha L., Rosaceae; and Vaccinium macrocarpon Aiton, Ericaceae. The spectrophotometric methods employed were DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and the Folin-Ciocalteu assays. The electroanalytical method used was voltammetry and it was developed a phenoloxidase based biosensor. The redox behavior observed for each herbal sample resulted in distinguishable voltammetric profiles. The highest electrochemical indexes were found to G. biloba and H. perforatum, corroborating to traditional spectrophotometric methods. Thus, the electroanalysis of herbal drugs, may be a promising tool for antioxidant potential assessment.

17.
Biosensors (Basel) ; 8(2)2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29762479

RESUMO

In this work, an innovative polyphenol oxidase biosensor was developed from Jenipapo (Genipa americana L.) fruit and used to assess phenolic compounds in industrial effluent samples obtained from a textile industry located in Jaraguá-GO, Brasil. The biosensor was prepared and optimized according to: the proportion of crude vegetal extract, pH and overall voltammetric parameters for differential pulse voltammetry. The calibration curve presented a linear interval from 10 to 310 µM (r² = 0.9982) and a limit of detection of 7 µM. Biosensor stability was evaluated throughout 15 days, and it exhibited 88.22% of the initial response. The amount of catechol standard recovered post analysis varied between 87.50% and 96.00%. Moreover, the biosensor was able to detect phenolic compounds in a real sample, and the results were in accordance with standard spectrophotometric assays. Therefore, the innovatively-designed biosensor hereby proposed is a promising tool for phenolic compound detection and quantification when environmental contaminants are concerned.


Assuntos
Catecol Oxidase/química , Frutas/química , Fenóis/química , Extratos Vegetais/química , Rubiaceae/química , Têxteis/estatística & dados numéricos
18.
Biosensors (Basel) ; 8(2)2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29614829

RESUMO

The vegetable kingdom is a wide source of a diverse variety of enzymes with broad biotechnological applications. Among the main classes of plant enzymes, the polyphenol oxidases, which convert phenolic compounds to the related quinones, have been successfully used for biosensor development. The oxidation products from such enzymes can be electrochemically reduced, and the sensing is easily achieved by amperometric transducers. In this work, the polyphenoloxidases were extracted from jurubeba (Solanum paniculatum L.) fruits, and the extract was used to construct a carbon paste-based biosensor for pharmaceutical analysis and applications. The assay optimization was performed using a 0.1 mM catechol probe, taking into account the amount of enzymatic extract (50 or 200 µL) and the optimum pH (3.0 to 9.0) as well as some electrochemical differential pulse voltammetric (DPV) parameters (e.g., pulse amplitude, pulse range, pulse width, scan rate). Under optimized conditions, the biosensor was evaluated for the quantitative determination of acetaminophen, acetylsalicylic acid, methyldopa, and ascorbic acid. The best performance was obtained for acetaminophen, which responded linearly in the range between 5 and 245 µM (R = 0.9994), presenting a limit of detection of 3 µM and suitable repeatability ranging between 1.52% and 1.74% relative standard deviation (RSD).


Assuntos
Acetaminofen/química , Técnicas Biossensoriais/métodos , Catecol Oxidase/metabolismo , Frutas/química , Solanum/química
19.
Eur J Pharm Sci ; 106: 231-243, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28599988

RESUMO

Dual 5-LOX/COX inhibitors are potential new dual drugs to treat inflammatory conditions. This research aimed to design, synthesis and to evaluate the anti-inflammatory and antinociceptive effects of the new compound, which is derived from nimesulide and darbufelone lead compounds. The new dual inhibitor 5-LOX/COX has the possible advantage of gastrointestinal safety. A voltammetric experiment was conducted to observe the drug's antioxidative effect. A formalin test, a hot plate test and carrageenan-induced mechanical hyperalgesia were employed to evaluate the analgesic nature of LQFM-091. To evaluate anti-inflammatory activity, we measured edema, leukocyte count, myeloperoxidase activity and cytokines levels in carrageenan-induced inflammation tests. We elucidated the underlying mechanisms by assessing the interaction the with COXs and LOX enzymes by colorimetric screening assay and molecular docking. The lethal dose (LD50) was estimated using 3T3 Neutral Red Uptake assay. Our results indicate that the LQFM-091 prototype is a powerful antioxidant, as well as able to inhibit COX-1, COX-2 and LOX activities. LQFM091 was classified in GHS category 4 (300

Assuntos
Inibidores de Ciclo-Oxigenase/uso terapêutico , Inibidores de Lipoxigenase/uso terapêutico , Fenóis/uso terapêutico , Células 3T3 , Animais , Carragenina , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Citocinas/imunologia , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Temperatura Alta , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Contagem de Leucócitos , Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/farmacologia , Camundongos , Simulação de Acoplamento Molecular , Medição da Dor , Peroxidase/imunologia , Fenóis/farmacologia , Estimulação Física , Pleurisia/induzido quimicamente , Pleurisia/tratamento farmacológico , Pleurisia/imunologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Sulfonamidas
20.
Sci Rep ; 7: 41326, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28145477

RESUMO

Microcystin-leucine arginine (MC-LR) is the most abundant and toxic secondary metabolite produced by freshwater cyanobacteria. This toxin has a high potential hazard health due to potential interactions with liver, kidney and the nervous system. The aim of this work was the design of a simple and environmentally friendly electrochemical system based on highly efficient nanostructured electrodes for the removal of MC-LR in tap water. Titania nanoparticles were deposited on carbon (graphite) under a simple and efficient microwave assisted approach for the design of the electrode, further utilized in the electrochemical remediation assays. Parameters including the applied voltage, time of removal and pH (natural tap water or alkaline condition) were investigated in the process, with results pointing to a high removal efficiency for MC-LR (60% in tap water and 90% in alkaline media experiments, under optimized conditions).


Assuntos
Carbono/química , Técnicas Eletroquímicas/métodos , Microcistinas/isolamento & purificação , Titânio/química , Purificação da Água/métodos , Água/química , Eletrodos , Toxinas Marinhas , Microcistinas/química , Espectrometria de Massas em Tandem
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