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1.
Med Pr ; 72(2): 145-154, 2021 Apr 15.
Artigo em Polonês | MEDLINE | ID: mdl-33783437

RESUMO

BACKGROUND: Naphthylamine (NA), i.e., 1-naphthylamine (1-NA) and 2-naphthylamine (2-NA) and its salts (2-naphthylamine hydrochloride and 2-naphthylamine acetate) are colorless crystalline solids. They have been used, among others, in the production of paints and dyes. In the European Union, 1-NA is classified as a toxic substance, and 2-NA and its salts as carcinogenic category 1A. The aim of this study was to develop a new method for the determination of NA, which will enable the determination of 1-NA and 2-NA and its salts in the working environment, in the concentration range of 0.3-6 µg/m3. MATERIAL AND METHODS: The method consists in passing the test air containing the substances to be determined through a glass fiber filter impregnated with sulphuric acid(VI). After recovery with water and sodium hydroxide solution followed by extraction into a solid on Oasis HLB columns, the solutions in methanol are analyzed using a high-performance liquid chromatograph with a fluorescence detector and Ultra C18 column. RESULTS: The method developed allows determining 1-NA and 2-NA and its salts in the concentration range of 0.3-6 µg/m3. The limit of detection for 1-NA is 81 pg/ml and for 2-NA - 80.6 pg/ml. CONCLUSIONS: The method is characterized by good precision and accuracy; it meets the requirements of European Standard PN-EN 482 and can be used by occupational hygiene laboratories to measure the level of 1-NA and 2-NA and its salts in workplace air to assess workers' exposure to these substances. Med Pr. 2021;72(2):145-54.


Assuntos
1-Naftilamina/análise , 2-Naftilamina/análise , Poluentes Ocupacionais do Ar/análise , Cromatografia Líquida de Alta Pressão/métodos , Monitoramento Ambiental/métodos , Confiabilidade dos Dados , Limite de Detecção
2.
Chemistry ; 26(44): 10064-10071, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32428299

RESUMO

Fluorescent sensors are a vital research tool, enabling the study of intricate cellular processes in a sensitive manner. The design and synthesis of responsive and targeted probes is necessary to allow such processes to be interrogated in the cellular environment. This remains a challenge, and requires methods for functionalisation of fluorophores with multiple appendages for sensing and targeting groups. Methods to synthesise more structurally complex derivatives of fluorophores will expand their potential scope. Most known 4-amino-1,8-naphthalimides are only functionalised at imide and 4-positions, and structural modifications at additional positions will increase the breadth of their utility as responsive sensors. In this work, methods for the incorporation of a hypoxia sensing group to 4-amino-1,8-naphthalimide were evaluated. An intermediate was developed that allowed us to incorporate a sensing group, targeting group, and ICT donor to the naphthalimide core in a modular fashion. Synthetic strategies for attaching the hypoxia sensing group and how they affected the fluorescence of the naphthalimide were evaluated by photophysical characterisation and time-dependent density functional theory. An extracellular hypoxia probe was then rationally designed that could selectively image the hypoxic and necrotic region of tumour spheroids. Our results demonstrate the versatility of the naphthalimide scaffold and expand its utility. This approach to probe design will enable the flexible, efficient generation of selective, targeted fluorescent sensors for various biological purposes.


Assuntos
1-Naftilamina/análogos & derivados , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Hipóxia/metabolismo , Naftalimidas/química , Naftalimidas/síntese química , Quinolonas/química , Quinolonas/síntese química , 1-Naftilamina/análise , 1-Naftilamina/síntese química , 1-Naftilamina/química , Linhagem Celular , Corantes Fluorescentes/química , Humanos , Naftalimidas/análise , Quinolonas/análise
3.
Biomed Chromatogr ; 32(6): e4207, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29430676

RESUMO

Naphthoquine (NQ) is one of important partner drugs of artemisinin-based combination therapy (ACT), which is recommended for the treatment of uncomplicated Plasmodium falciparum. NQ shows a high cure rate after a single oral administration. It is absorbed quickly (time to peak concentration 2-4 h) and has a long elimination half-life (255 h). However, the metabolism of NQ has not been clarified. In this work, the metabolite profiling of NQ was studied in six liver microsomal incubates (human, cynomolgus monkey, beagle dog, mini pig, rat and CD1 mouse), seven recombinant CYP enzymes (1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4) and rat (plasma, urine, bile and feces) using liquid chromatography tandem high-resolution LTQ-Orbitrap mass spectrometry (HRMSn ) in conjunction with online hydrogen/deuterium exchange. The biological samples were pretreated by protein precipitation and solid-phase extraction. For data processing, multiple data-mining tools were applied in tandem, i.e. background subtraction and followed by mass defect filter. NQ metabolites were characterized by accurate MS/MS fragmentation characteristics, the hydrogen/deuterium exchange data and cLogP simulation. As a result, five phase I metabolites (M1-M5) of NQ were characterized for the first time. Two metabolic pathways were involved: hydroxylation and N-oxidation. This study demonstrates that LC-HRMSn in combination with multiple data-mining tools in tandem can be a valuable analytical strategy for rapid metabolite profiling of drugs.


Assuntos
1-Naftilamina/análogos & derivados , Aminoquinolinas/metabolismo , Antimaláricos/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , 1-Naftilamina/análise , 1-Naftilamina/metabolismo , Aminoquinolinas/análise , Animais , Antimaláricos/análise , Biologia Computacional , Mineração de Dados , Medição da Troca de Deutério , Feminino , Masculino , Ratos Wistar
4.
Int J Occup Med Environ Health ; 30(4): 579-591, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28584318

RESUMO

OBJECTIVES: 1,5-Naphthalene diisocyanate (NDI) is used in the plastic industry as a curing agent. 1,5-Naphthalene diisocyanate is classified as a sensitizing agent. The objective of this study has been to develop biomonitoring methods for the evaluation of exposure to NDI. MATERIAL AND METHODS: We obtained blood and urine samples from a group of 20 male workers exposed to NDI. The workers answered a questionnaire about their exposure history, job description, the number of years with the company and the time spent working with NDI over the 10 days of the study. Total plasma, albumin, and urine were analyzed for the presence of 1,5-naphthalenediamine (NDA) after acid hydrolysis using gas chromatography-mass spectrometry (GC-MS). RESULTS: 1,5-Naphthalenediamine was found in about 60% of the samples obtained from the workers. 1,5-Naphthalenediamine was obtained after acid hydrolysis of plasma, albumin, and urine at levels up to 1.5 pmol NDA/mg of plasma proteins, 1.15 pmol NDA/mg of albumin, and 55.3 pmol NDA/ml of urine, respectively. CONCLUSIONS: 1,5-Naphthalenediamine found in urine correlates best with the plasma levels (r = 0.91, p < 0.01). The albumin-adduct levels did not correlate with the NDI-specific immunoglobulin E (IgE) or total IgE present in the workers. The adduct and metabolite levels correlate with the air levels of NDI. Int J Occup Med Environ Health 2017;30(4):579-591.


Assuntos
1-Naftilamina/análogos & derivados , Isocianatos/análise , Exposição Ocupacional/análise , 1-Naftilamina/análise , Adulto , Albuminas/química , Biomarcadores/sangue , Biomarcadores/urina , Monitoramento Ambiental/métodos , Humanos , Isocianatos/sangue , Isocianatos/urina , Masculino , Pessoa de Meia-Idade
5.
J Chromatogr A ; 1482: 39-47, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-28027837

RESUMO

A fully automated, rapid, and reliable method for simultaneous determination of six carcinogenic primary aromatic amines (AAs), including o-toluidine (o-TOL), 2, 6-dimethylaniline (2, 6-DMA), o-anisidine (o-ASD), 1-naphthylamine (1-ANP), 2-naphthylamine (2-ANP), and 4-aminobiphenyl (4-ABP), in mainstream cigarette smoke was established. The proposed method was based on two-dimensional online solid phase extraction combined with liquid chromatography tandem mass spectrometry (SPE/LC-MS/MS). The particulate phase of the mainstream cigarette smoke was collected on a Cambridge filter pad and pretreated via ultrasonic extraction with 2% formic acid (FA), while the gas phase was trapped by 2% FA without pretreatment for determination. The two-dimensional online SPE comprised of two cartridges with different absorption characteristics was applied for sample pretreatment. Analysis was performed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) under multiple reaction monitoring mode. Each sample required about 0.5h for solid phase extraction and analysis. The limit of detections (LODs) for six AAs ranged from 0.04 to 0.58ng/cig and recoveries were within 84.5%-122.9%. The relative standard deviations of intra- and inter-day tests for 3R4F reference cigarette were less than 6% and 7%, respectively, while no more than 7% and 8% separately for a type of Virginia cigarette. The proposed method enabled minimum sample pretreatment, full automation, and high throughput with high selectivity, sensitivity, and accuracy. As a part of the validation procedure, fifteen brands of cigarettes were tested by the designed method.


Assuntos
Carcinógenos/análise , Nicotiana/química , Fumaça/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , 1-Naftilamina/análise , Compostos de Aminobifenil/análise , Compostos de Anilina/análise , Cromatografia Líquida , Limite de Detecção , Produtos do Tabaco/classificação , Toluidinas/análise
6.
J Chromatogr A ; 1432: 84-91, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26787165

RESUMO

Metal-organic framework (MOF) MIL-100(Fe) with well-defined thickness was homogenously coated onto the outer surface of magnetic microparticles via a liquid-phase epitaxy method. The as-synthesized MIL-100(Fe) was used as stationary phase for high-performance liquid chromatography (HPLC) and separations of two groups of mixed aromatic hydrocarbons (toluene, styrene and p-xylene; acetanilide, 2-nirtoaniline and 1-naphthylamine) using methanol/water as mobile phase were performed to evaluate its performance. Increasing water content of the mobile phase composition can greatly improve the separations on the expense of a longer elution time. Stepwise elution significantly shortens the elution time of acetanilide, 2-nirtoaniline and 1-naphthylamine mixtures, while still achieving a baseline separation. Combining the experimental results and in-depth modeling using a recently developed chromatographic software (ChromX), adsorption equilibrium parameters, including the affinities and maximum capacities, for each analyte toward the MIL-100(Fe) are obtained. In addition, the pore diffusivity of aromatic hydrocarbons within MIL-100(Fe) was determined to be 5×10(-12)m(2)s(-1). While the affinities of MIL-100(Fe) toward the analyte molecules differs much, the maximum capacities of the analytes are in a narrow range with q*MOFmax,toluene=3.55molL(-1), q*MOFmax,styrene or p-xylene=3.53molL(-1), and q*MOFmax,anilines=3.12molL(-1) corresponding to approximately 842 toluene and 838 styrene or p-xylene, and 740 aniline molecules per MIL-100(Fe) unit cell, respectively.


Assuntos
Hidrocarbonetos Aromáticos/análise , Ferro , Nanopartículas Metálicas , Compostos Organometálicos/química , 1-Naftilamina/análise , Acetanilidas/análise , Compostos de Anilina/análise , Cromatografia Líquida de Alta Pressão , Estireno/análise , Tolueno/análise , Xilenos/análise
7.
Anal Chim Acta ; 866: 48-58, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25732692

RESUMO

Natural organic matter (NOM) is a complex and non-uniform mixture of organic compounds which plays an important role in environmental processes. Due to the complexity, it is challenging to obtain fully detailed structural information about NOM. Although Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) has been demonstrated to be a powerful tool for providing molecular information about NOM, multiple ionization methods are needed for comprehensive characterization of NOM at the molecular level considering the ionizing selectivity of different ionization methods. This paper reports the first use of matrix assisted laser desorption/ionization (MALDI) method coupled with FT-ICR-MS for molecular characterization of NOM within a mass range of 200-800 Da. The mass spectral data obtained by MALDI were systematically compared with data generated by electrospray ionization (ESI). It showed that complementary molecular information about NOM which could not be detected by ESI, were provided by MALDI. More unsaturated and aromatic constituents of NOM with lower O/C ratio (O/C ratio<0.5) were preferentially ionized in MALDI negative mode, whereas more polar constituents of NOM with higher O/C ratio were preferentially ionized in ESI negative mode. Molecular anions of NOM appearing at even m/z in MALDI negative ion mode were detected. The results show that NOM molecules with aromatic structures, moderate O/C ratio (0.7>O/C ratio>0.25) and lower H/C ratio were liable to form molecular anions at even m/z, whereas those with higher H/C ratio are more likely to form deprotonated ions at odd m/z. It is speculated that almost half of the NOM molecules identified by MALDI may be aromatic or condensed aromatic compounds with special groups which are liable to absorb electron from other molecules to generate free radical anions during MALDI ionization.


Assuntos
Compostos Orgânicos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , 1-Naftilamina/química , Análise de Fourier , Compostos Orgânicos/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação
8.
Artigo em Inglês | MEDLINE | ID: mdl-24735928

RESUMO

Urinary aromatic amines (AAs) could be used as biomarkers for human exposure to AAs in cigarette smoke. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of urinary AAs (i.e. 1-naphthylamine (1-NA), 2-naphthylamine (2-NA), 3-aminobiphenyl (3-ABP) and 4-aminobiphenyl (4-ABP)) in smokers and nonsmokers. A molecularly imprinted polymers (MIPs) solid phase extraction (SPE) cartridge was applied to purify urine samples and no derivatization reaction was involved. Each analytes used respective stable isotope internal standards, which could well compensate matrix effect. Lower limit of detections (LODs) for four AAs were obtained and in the range of 1.5-5ngL(-1). Recovery ranged from 87.7±4.5% to 111.3±6.4% and precision were less than 9.9%. The method was applied to analyze urine samples of 40 smokers and 10 nonsmokers. The 24h urinary excretion amounts of total AAs were higher for smokers compared with nonsmokers. What's more, 1-NA, 3-ABP and 4-ABP excretion amounts showed significant differences (p<0.05) between smokers and nonsmokers.


Assuntos
1-Naftilamina/análise , 2-Naftilamina/análise , Compostos de Aminobifenil/urina , Cromatografia Líquida de Alta Pressão , Fumar/urina , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Limite de Detecção , Impressão Molecular/métodos , Polímeros/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Urinálise/métodos
9.
Biosens Bioelectron ; 48: 238-43, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23693094

RESUMO

The amino-substituted naphthalene compounds, such as 1,8-diaminonaphthalene (1,8-DANAP), 2,3-diaminonaphthalene (2,3-DANAP), 1,5-diaminonaphthalene (1,5-DANAP), 1-naphthylamine (1-NAP) and 2-naphthylamine (2-NAP), were investigated by electrochemical impedance spectroscopy (EIS), which was based on the interaction with hairpin DNA immobilized on the gold electrodes. Upon hairpin DNA interacting with the target chemicals, the charge transfer resistance (RCT) of the hairpin DNA films was significantly decreased and the charge transfer resistance change (ΔR(CT)) decreased in a sequence of ΔR(CT) (1,8-DANAP)>ΔR(CT) (2,3-DANAP)>ΔR(CT) (1,5-DANAP)>ΔR(CT) (1-NAP)>ΔR(CT) (2-NAP). The ΔR(CT) changes were due to the difference in the binding constant (K(SV)) of the target chemicals to DNA. In addition, the interaction mechanism was further explored using 1,8-DANAP as a model analyte by fluorescence spectra, Raman spectroscopy, differential pulse voltammetry (DPV) and EIS, correspondingly. The results demonstrated that the amino-substituted naphthalene compounds intercalated into "stem" appearing in the hairpin DNA. Moreover, the hairpin DNA sensor exhibited high sensitivity to the amino-substituted naphthalene compounds with the detection limit of nano-mole, and maintained high selectivity over other selected environmental pollutants. Finally, the DNA sensor was challenged in natural water sample with a recovery of 96-102%, which offered a platform for prospective future development of a simple, rapid, sensitive and low-cost assay for the detection of target aromatic amine pollutants.


Assuntos
1-Naftilamina/análise , DNA/química , Espectroscopia Dielétrica/métodos , Lagos/análise , Poluentes Químicos da Água/análise , 2-Naftilamina/análogos & derivados , 2-Naftilamina/análise , Limite de Detecção
10.
Environ Toxicol Chem ; 32(3): 493-500, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23212963

RESUMO

Carbon nanotubes (CNTs) can exist in the form of colloidal suspension in aquatic environments, particularly in the presence of natural organic matter or surfactants, and may significantly affect the fate and transport of organic contaminants. In the present study, the authors examined the adsorption of phenanthrene, 2-naphthol, and 1-naphthylamine to three colloidal CNTs, including a stable suspension of oxidized multiwalled carbon nanotubes (O-MWNT), a humic acid (HA)-modified colloidal O-MWNT, and a sodium dodecyl sulfate (SDS)-modified colloidal O-MWNT. All three colloidal O-MWNTs exhibit strong adsorption affinities to the three test compounds (with K(OC) values orders of magnitude greater than those of natural organic matter), likely resulting from strong nonhydrophobic interactions such as π-π electron donor-acceptor interactions and Lewis acid-base interactions. When thoroughly mixed, HA (at ∼310 mg HA/g CNT) and SDS (at ∼750 mg SDS/g CNT) significantly affected the aggregation properties of O-MWNT, causing individually dispersed tubes to form a loosely entangled network. The effects of HA or SDS modification on adsorption are twofold. Adsorption of HA/SDS significantly reduces surface areas of O-MWNT; however, the entangled network allows adsorbate molecules to interact simultaneously with multiple tubes. An important implication is that humic substances and surfactant-like materials not only facilitate the formation of colloidal carbon nanoparticles but also affect how these colloidal carbon nanoparticles adsorb organic contaminants.


Assuntos
1-Naftilamina/química , Substâncias Húmicas , Nanotubos de Carbono/química , Naftóis/química , Fenantrenos/química , Tensoativos/química , Poluentes Químicos da Água/química , 1-Naftilamina/análise , Adsorção , Modelos Químicos , Naftóis/análise , Fenantrenos/análise , Dodecilsulfato de Sódio/química , Poluentes Químicos da Água/análise
11.
Forensic Sci Int ; 223(1-3): 349-52, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23131307

RESUMO

Sertraline is a commonly prescribed selective inhibitor of serotonin uptake used for the treatment of mental depression and anxiety. Central blood and liver concentrations of sertraline (norsertraline) are compared to levels in peripheral blood in nine medical examiner cases. Specimens were initially screened for alcohol and simple volatiles by GC-FID headspace analysis, ELISA for drugs of abuse, and alkaline drugs by GC/MS. Sertraline, when detected by the alkaline drug screen, was subsequently confirmed and quantified by a specific GC-NPD procedure. Data suggest that when ingested with other medications, sertraline may be a contributing factor in death. Sertraline (norsertraline) concentrations ranged from 0.13 (0.11) to 2.1 (6.0) mg/L in peripheral blood, from 0.18 (0.12) to 2.0 (6.7) mg/L in central blood, and 21 to 160 mg/kg in liver. Sertraline central blood to peripheral blood ratios averaged 1.22±0.85 (mean±standard deviation). The liver to peripheral blood ratios, on the other hand, were markedly higher and averaged 97±40 (mean±standard deviation). Given that a liver to peripheral blood ratio exceeding 20 is indicative of propensity for significant postmortem redistribution, these data confirm that sertraline is prone to marked postmortem redistribution.


Assuntos
Inibidores Seletivos de Recaptação de Serotonina/análise , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Sertralina/análise , Sertralina/farmacocinética , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , 1-Naftilamina/farmacocinética , Analgésicos Opioides/análise , Analgésicos Opioides/farmacocinética , Antidepressivos/análise , Antidepressivos/farmacocinética , Depressores do Sistema Nervoso Central/análise , Depressores do Sistema Nervoso Central/farmacocinética , Cromatografia Gasosa , Ensaio de Imunoadsorção Enzimática , Etanol/análise , Ionização de Chama , Toxicologia Forense , Conteúdo Gastrointestinal/química , Humanos , Hipnóticos e Sedativos/análise , Hipnóticos e Sedativos/farmacocinética , Fígado/química
12.
Chem Senses ; 37(2): 141-50, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21852709

RESUMO

Odorant-binding proteins (OBPs) are found in both insects and vertebrates, and it is believed that they are involved in chemical communication. In this study, we identify and express 2 OBPs from the scarab beetle, Holotrichia oblita Faldermann (Coleoptera: Scarabaeidae). HoblOBP1 shows more similarities with other scarab beetle OBPs, whereas HoblOBP2 is more diverse. N-phenyl-1-naphthylamine (1-NPN) is used as a fluorescent probe in ligand-binding experiment, and results indicate that both HoblOBPs prefer plant volatiles to putative H. oblita sex pheromones. HoblOBP1 shows binding affinity to a wider range of test compounds, but HoblOBP2 displays more specific binding affinity. Cinnamaldehyde and 2,4-di-tert-butylphenol bind to HoblOBP1 can elicit strong electrophysiological responses of the antennae from female H. oblita adults, respectively. Methyl salicylate also shows good affinity to HoblOBP2 and it can elicit moderate electrophysiological responses. Although, ß-ionone is one of the ligands of the strongest binding, it elicits a weak electrophysiological response. In the immunocytochemical analysis, we observe that HoblOBP1 and HoblOBP2 are coexpressed in sensilla basiconica and placodea in both sexes.


Assuntos
Antenas de Artrópodes/fisiologia , Proteínas de Insetos/metabolismo , Receptores Odorantes/metabolismo , Sensilas/fisiologia , Olfato/fisiologia , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , Acroleína/análogos & derivados , Acroleína/metabolismo , Sequência de Aminoácidos , Animais , Besouros , Feminino , Proteínas de Insetos/genética , Masculino , Dados de Sequência Molecular , Norisoprenoides/metabolismo , Fenóis/metabolismo , Filogenia , Ligação Proteica , Isoformas de Proteínas , Receptores Odorantes/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Salicilatos/metabolismo , Atrativos Sexuais/metabolismo , Olfato/efeitos dos fármacos , Especificidade por Substrato
13.
Biosens Bioelectron ; 26(11): 4520-5, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21641788

RESUMO

The first polyurethane based magnetic-MIP for the selective detection of 1-naphthylamine (1-NA) in drinking water has been synthesised. The synthesis has been carried out in a two-step process: first,the incorporation of magnetite-coated-oleic acid nanoparticles (-Fe3O4-OA) into a lipophilic polymeric matrix (poly-MMA-co-EDMA) and second, the encapsulation of these magnetic seeds into the MIP structure by precipitation polymerisation. The mag-MIP was first RHTEM imaged showing a well-organised material with magnetite within the material and the imprinted polymer coating the magnetic core. Thereafter,it was evaluated by batch rebinding analysis and the derived Freundlich isotherm, calculating the number of binding sites (N(K(min)-K(max))=2.63 and 0.79 mmol g⁻¹, for mag-MIP and mag-NIP, respectively)and apparent average adsorption constant (K(K(min)-K(max))=3.31 and 3.06 mmol⁻¹, for mag-MIP and mag-NIP, respectively) showing a very effective imprinting process.We have also developed a magnetic optical sensor MIP by using an optical fiber coupled with a magnetic separator. An unexpected selectivity for 1-NA was revealed allowing the detection of this molecule in water, even in the presence of 4 structurally related compounds (2-naphthylamine, 1-naphthol, 2-naphthol and 1-naphthalenemethylamine), with a low limit of detection (LOD) = 18 ng mL⁻¹. Finally, we applied this new hybrid material to the analysis of 1-NA in tap and mineral waters, obtaining a 91.6%average recovery rate.


Assuntos
1-Naftilamina/análise , Técnicas Biossensoriais/métodos , Poluentes Químicos da Água/análise , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Impressão Molecular , Fibras Ópticas , Polímeros/síntese química , Polímeros/química , Poliuretanos/química , Abastecimento de Água
14.
Peptides ; 32(7): 1488-95, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21664394

RESUMO

Enantiomeric amphipathic α-helical antibacterial peptides were synthesized and their biophysical and biological properties under different physiological conditions were studied. In the absence of physiological factors, the L- and D-peptides exhibited similar antimicrobial activities against a broad spectrum of bacteria, even against clinical isolates with resistance to traditional antibiotics. However, in the presence of NaCl, CaCl2 or human serum albumin (HSA) at physiological concentrations, the enantiomers revealed bacterium-species dependent attenuations in antibacterial activity. In the presence of salts the electrostatic interaction between the peptides and the biomembrane was inhibited. Salts, especially CaCl2 weakened the ability of the peptides to permeabilize the outer membrane of Gram-negative bacteria, as determined by a 1-N-phenylnaphthylamine uptake assay. HSA exhibited variable inhibitory effects on the activity of the peptides when incubated with different bacterial strains. The peptides showed different binding association abilities to HSA at different molar ratios, regardless of their chirality, resulting in reduced peptide biological activity. The D-peptide performed better than its L-enantiomer in all conditions tested because of its resistance to proteolysis, and may therefore represent a promising candidate for development as a therapeutic agent.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , Sequência de Aminoácidos , Antibacterianos/antagonistas & inibidores , Antibacterianos/síntese química , Peptídeos Catiônicos Antimicrobianos/antagonistas & inibidores , Peptídeos Catiônicos Antimicrobianos/síntese química , Cloreto de Cálcio/efeitos adversos , Cloreto de Cálcio/farmacologia , Cromatografia de Fase Reversa , Dicroísmo Circular , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Albumina Sérica/efeitos adversos , Albumina Sérica/farmacologia , Cloreto de Sódio/efeitos adversos , Cloreto de Sódio/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
15.
Se Pu ; 29(11): 1122-7, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22393703

RESUMO

A method for the determination of 4,4'-methylenedianiline, aniline, o-anisidine, 3, 4-dimethylaniline, p-anisidine, 3-aminophenol, 1-naphthylamine in hair dyes was established by capillary electrophoresis coupled with field-amplified sample stacking. The optimum running buffer was an aqueous solution containing 0.15 mol/L NaH2PO4 and 0.015 mol/L trolamine (pH 2.3), and the baseline separation was achieved within 6.5 min. The effects of phosphoric acid and acetonitrile concentration in the sample matrix, the length of the preinjection water plug, and the sample injection voltage and time on the stacking efficiency were investigated. The optimum stacking conditions for the real samples included a water plug of 3.45 kPa (0.5 psi) x 6 s, the addition of 40% (v/v) acetonitrile and 0.6 x 10(-3) mol/L phosphoric acid to the sample solution and a sample injection of 10 kV x 10 s. The seven analytes all showed good linearities (R2 > 0.996) within 3 - 1 000 microg/L, with the detection limits in the range of 0.26 - 2.75 microg/L. The method was shown to provide over 1 - 3 magnitudes of sensitivity enhancement. 3-Aminophenol was found in two black hair dyes, and the amounts were 7.32 mg/g and 1.34 mg/g, individually. The recoveries ranged from 74% - 108%. The proposed approach may find widespread applications for the determination of trace aromatic amines and other cationic analytes in various sample matrixes.


Assuntos
1-Naftilamina/análise , Compostos de Anilina/análise , Eletroforese Capilar/métodos , Tinturas para Cabelo/química , Aminofenóis/análise
16.
East Mediterr Health J ; 16(1): 82-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20214163

RESUMO

We estimated pollution in Lake Edku and the Mediterranean Sea, El-Maadiya Region, with 3 aromatic amines (1-naphthylamine, 2-naphthylamine and benzidine) in the muscle tissue of fish. There were marked seasonal variations in the aromatic amine levels. We also determined oxidative stress (blood glutathione, and catalase activity) and genotoxic effects (chromosomal aberrations and urinary metabolites) in fishermen from each area. The fishermen suffered from oxidative stress and had high levels of the urinary metabolite sulfanilamide [mean (microg/mg creatinine): Lake Edku 20.7, Mediterranean 14.5, controls 5.3]. Frequencies for total chromosomal aberrations were significantly raised in the peripheral blood lymphocytes of fishermen in both areas [frequency (per 100 metaphases): Mediterranean 67, Lake Edku 45, controls 14].


Assuntos
Exposição Ambiental/análise , Pesqueiros , Peixes , Água Doce/análise , Poluentes Químicos da Água/análise , 1-Naftilamina/efeitos adversos , 1-Naftilamina/análise , 2-Naftilamina/efeitos adversos , 2-Naftilamina/análise , Adulto , Animais , Benzidinas/efeitos adversos , Benzidinas/análise , Estudos de Casos e Controles , Catalase/sangue , Aberrações Cromossômicas/estatística & dados numéricos , Dano ao DNA/fisiologia , Egito/epidemiologia , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Monitoramento Epidemiológico , Peixes/metabolismo , Água Doce/química , Glutationa/sangue , Humanos , Masculino , Mar Mediterrâneo/epidemiologia , Estresse Oxidativo/fisiologia , Estações do Ano , Poluentes Químicos da Água/efeitos adversos
17.
J Hazard Mater ; 144(1-2): 67-72, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17097225

RESUMO

A simple and rapid analytical method for determining 1-naphthylamine was proposed by perturbation with different amounts of 1-naphthylamine on the classical Belousov-Zhabotinskii (B-Z) oscillating chemical system. The results show that the changes both in oscillating period and amplitude were linearly proportional to the logarithm of the concentration of 1-naphthylamine (logC) very well ranging from 7.08x10(-5) to 7.08x10(-6) molL(-1) and 7.08x10(-5) to 1.0x10(-6) molL(-1), with the corresponding regression coefficient are 0.9957 and 0.9922, respectively. For the later, a lower detection limit of 5.64x10(-9) molL(-1) was obtained. Influence of injection point, temperature and reactant variables on this oscillating system was also investigated in detailed. The results obtained were compared with other determination methods. A possible reaction mechanism was interpreted by using bromide ion selective electrode to inspect the concentration change of Br(-) ion in the oscillating process.


Assuntos
1-Naftilamina/análise , Poluentes Químicos da Água/análise , 1-Naftilamina/química , Bromatos/química , Cério/química , Malonatos/química , Reprodutibilidade dos Testes , Ácidos Sulfúricos/química , Poluentes Químicos da Água/química
18.
Xenobiotica ; 35(8): 839-52, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16278195

RESUMO

Metabonomics using high-resolution 1H-NMR spectroscopy of biofluids and pattern recognition is highly successful at distinguishing both organ- and sub-organ-specific toxicity. In the current study, this technique was investigated to distinguish the different biological effects caused by 1-naphthylisothiocyanate (ANIT)-induced hepatotoxicity in the rat from that induced by exposure to 1-naphthylisocyanate (NI) and 1-naphthylamine (NA), two products of the metabolism of ANIT. While all three toxicants produced perturbations in similar urinary metabolites, principal components analysis of the temporal progression identified that the rapid initial glycosuria associated with ANIT toxicity was also present with NI but not NA dosing. However, longer-term perturbations in the urinary excretion of succinate, lactate and acetate were common to all three toxicants. The metabolic effects of the three compounds were also followed in blood plasma and liver tissue. Of the three toxicants, the most marked perturbations were induced by ANIT exposure, then NI, thereby indicating the effects of ANIT, NI and NA toxicity were distinct, with ANIT being the most, and NA the least, toxic of the three compounds. This indicates that metabonomics may be useful for following severity and mechanisms of toxicity in a series of related compounds during drug development.


Assuntos
1-Naftilisotiocianato/metabolismo , 1-Naftilisotiocianato/toxicidade , Líquidos Corporais/química , Doença Hepática Induzida por Substâncias e Drogas , 1-Naftilamina/análise , 1-Naftilisotiocianato/farmacologia , Animais , Análise Química do Sangue , Isocianatos/análise , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias/sangue , Hepatopatias/metabolismo , Hepatopatias/urina , Espectroscopia de Ressonância Magnética , Especificidade de Órgãos , Análise de Componente Principal , Ratos , Ratos Sprague-Dawley , Urina/química
19.
Luminescence ; 20(4-5): 331-3, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16134221

RESUMO

In this paper, an internal conversion (IC) fluorescence probe N-(o-boronic acid)benzyl-1-naphthylamine (BBNA) was prepared from 1-naphthylamine and 2-formylbenzeneboronic acid. The fluorescence parameters of BBNA were investigated in a variety of solvents. When BBNA interacted with D-fructose in phosphate buffer solution of 30% MeOH, pH 8.21 (v/v), the fluorescence intensity increased and emission maximum red-shifted slightly with increasing D-fructose concentration. In the presence of D-fructose, the fluorescence quantum yield of BBNA increased with increasing solvent polarity, suggesting that internal conversion (IC) occurred with BBNA. The binding force of BBNA with d-fructose was the strongest, and the stability constant (K) of D-fructose was 99.9 mol/L. Therefore, a selective recognition system based on IC was constructed for D-fructose.


Assuntos
Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Glucanos/análise , Glucanos/química , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , 1-Naftilamina/química , Ácidos Borônicos/análise , Ácidos Borônicos/química , Frutose/química , Frutose/farmacologia , Concentração de Íons de Hidrogênio , Estrutura Molecular , Fotoquímica , Espectrometria de Fluorescência
20.
Zhong Yao Cai ; 24(3): 176-8, 2001 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12587172

RESUMO

Essential oils from Artemisia annul L. were extracted with CO2 supercritical fluid and steam distilation. The essential oils were analyzed and contrasted by GC-MS. 114 components were identified by computer index. The rate of total components by supercritical CO2 fluid extraction and steam distillation were 81.24% and 85.75% respectively. Some of them such as diphenylene-Methane, Phenyl-1-naphthylamine were discovered from the plant for the first time.


Assuntos
Artemisia annua/química , Óleos Voláteis/química , Óleos de Plantas/química , 1-Naftilamina/análogos & derivados , 1-Naftilamina/análise , Compostos Benzidrílicos/análise , Cromatografia com Fluido Supercrítico , Destilação , Medicamentos de Ervas Chinesas/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação
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