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1.
Braz. j. biol ; 82: e235612, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153466

RESUMO

Abstract The experiment was carried out on mango cv. Dusehri to investigate the effect of N, P and K fertilizers on vegetative, reproductive growth, yield and fruit quality. Eight different fertilizer combinations such as T1 (control), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) and T8 (NPK) were used. Individual or combine fertilizer application of N (1000 g), P (750 g) and K (750 g) were applied during growing season in February and August. All the treatments significantly influenced on vegetative growth, flowering, fruiting, yield and other physiochemical attributes of mango as compared to control. Least effect was observed with individual fertilizer application while combine fertilizer treatments enhanced most of the investigated parameters. Especially, qualitative traits showed non-significant differences between treated and untreated mango trees. However, among the different treatments T8 (NPK) showed significance for fruiting aspects such as maximum size of growth flushes (177.51 mm), total number of panicles/tree (845), total number of flowers/panicle (974), sex ratio (69.18%), fruit retention (13.85%), total number of fruits/tree (379), yield (82 kg/tree), fruit weight (197.5 g), pulp weight (135.5 g) and physiochemical parameters namely TSS (24.53), Vit. C (57.63 mg/100 mL) and total sugar (20.84%). In general, combine application of NPK (T8) were the most effective in enhancing fruiting aspects, yield, physiochemical characteristics as well as improved fruit quality of mango trees.


Resumo O experimento foi realizado em manga cv. Dusehri para investigar o efeito dos fertilizantes N, P e K no crescimento vegetativo, reprodutivo, produtividade e de qualidade do fruto. Foram utilizadas oito combinações diferentes de fertilizantes: T1 (controle), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) e T8 (NPK). Cada tratamento de N (1.000 g), P (750 g) e K (750 g) foi aplicado duas vezes durante a estação de crescimento em fevereiro e agosto. Todos os tratamentos influenciaram significativamente o crescimento vegetativo, floração, frutificação, produtividade e outros atributos físico-químicos da manga em relação ao controle. Menos efeito foi observado com a aplicação individual de fertilizante, enquanto os tratamentos combinados aumentaram a maioria dos parâmetros investigados. Especialmente as características qualitativas mostraram diferenças não significativas entre mangueiras tratadas e não tratadas. No entanto, entre os diferentes tratamentos, T8 (NPK) apresentou significância para aspectos de frutificação, como tamanho máximo de folgas de crescimento (177,51 mm), número total de panículas/árvore (845), número total de flores/panícula (974), razão sexual (69,18%), retenção de frutos (13,85%), número total de frutos/árvore (379), produção (82 kg/árvore), peso do fruto (197,5 g) e peso da polpa (135,5 g), além de parâmetros físico-químicos, como TSS (24,53), vitamina C (57,63 mg/100 mL) e açúcar total (20,84%). Em geral, a aplicação combinada de NPK (T8) foi a mais eficaz no aprimoramento dos aspectos de frutificação, produtividade, características físico-químicas, além da melhoria da qualidade dos frutos das mangueiras.

2.
Braz J Biol ; 82: e235612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681899

RESUMO

The experiment was carried out on mango cv. Dusehri to investigate the effect of N, P and K fertilizers on vegetative, reproductive growth, yield and fruit quality. Eight different fertilizer combinations such as T1 (control), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) and T8 (NPK) were used. Individual or combine fertilizer application of N (1000 g), P (750 g) and K (750 g) were applied during growing season in February and August. All the treatments significantly influenced on vegetative growth, flowering, fruiting, yield and other physiochemical attributes of mango as compared to control. Least effect was observed with individual fertilizer application while combine fertilizer treatments enhanced most of the investigated parameters. Especially, qualitative traits showed non-significant differences between treated and untreated mango trees. However, among the different treatments T8 (NPK) showed significance for fruiting aspects such as maximum size of growth flushes (177.51 mm), total number of panicles/tree (845), total number of flowers/panicle (974), sex ratio (69.18%), fruit retention (13.85%), total number of fruits/tree (379), yield (82 kg/tree), fruit weight (197.5 g), pulp weight (135.5 g) and physiochemical parameters namely TSS (24.53), Vit. C (57.63 mg/100 mL) and total sugar (20.84%). In general, combine application of NPK (T8) were the most effective in enhancing fruiting aspects, yield, physiochemical characteristics as well as improved fruit quality of mango trees.


Assuntos
Mangifera , Animais , Aves , Fertilizantes , Frutas , Árvores
4.
J Clin Neurosci ; 75: 218-220, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32249175

RESUMO

Pneumocephalus describes the presence of air within the cranial cavity and is often self-limiting. Tension pneumocephalus is a neurosurgical emergency manifested by headaches, seizures, reduced consciousness and even death resulting from raised intracranial pressure. Differentiating both entities clinically is often challenging but crucial. We present a case involving a sixty-year-old male who was transferred to our unit after he collapsed while undergoing rehabilitation. The patient had undergone a combined bifrontal craniotomy and transnasal endoscopic resection of recurrent sinonasal adenocarcinoma with anterior skull base involvement eight days prior. Imaging demonstrated the classic Mt. Fuji sign and a diagnosis of tension pneumocephalus was formed. The patient proceeded for definitive management which included a multi-layered repair of the anterior skull base. The three mechanisms that propose the development of tension pneumocephalus include the ball-valve mechanism, the inverted soda-bottle effect and rarely, infection from gas forming organisms. A review of current literature on PubMed/MEDLINE revealed tension pneumocephalus after skull base surgery to be a rare entity with only eleven cases reported. Most patients achieved complete recovery of symptoms post-treatment. Clinicians should recognise tension pneumocephalus as a potential complication after skull base surgery. Accurate diagnosis requires appreciation of imaging features and a high index of suspicion. Prompt management is imperative to prevent possible devastating outcomes.


Assuntos
Pneumocefalia/diagnóstico por imagem , Pneumocefalia/etiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Base do Crânio/diagnóstico por imagem , Base do Crânio/cirurgia , Craniotomia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Neuroendoscopia/efeitos adversos , Procedimentos Neurocirúrgicos/efeitos adversos
5.
Nat Mater ; 19(4): 381-385, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31959951

RESUMO

The search continues for nickel oxide-based materials with electronic properties similar to cuprate high-temperature superconductors1-10. The recent discovery of superconductivity in the doped infinite-layer nickelate NdNiO2 (refs. 11,12) has strengthened these efforts. Here, we use X-ray spectroscopy and density functional theory to show that the electronic structure of LaNiO2 and NdNiO2, while similar to the cuprates, includes significant distinctions. Unlike cuprates, the rare-earth spacer layer in the infinite-layer nickelate supports a weakly interacting three-dimensional 5d metallic state, which hybridizes with a quasi-two-dimensional, strongly correlated state with [Formula: see text] symmetry in the NiO2 layers. Thus, the infinite-layer nickelate can be regarded as a sibling of the rare-earth intermetallics13-15, which are well known for heavy fermion behaviour, where the NiO2 correlated layers play an analogous role to the 4f states in rare-earth heavy fermion compounds. This Kondo- or Anderson-lattice-like 'oxide-intermetallic' replaces the Mott insulator as the reference state from which superconductivity emerges upon doping.

7.
Phys Rev Lett ; 121(12): 127001, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30296157

RESUMO

We report an angle-resolved photoemission spectroscopy study of the iron-based superconductor family, Ba_{1-x}Na_{x}Fe_{2}As_{2}. This system harbors the recently discovered double-Q magnetic order appearing in a reentrant C_{4} phase deep within the underdoped regime of the phase diagram that is otherwise dominated by the coupled nematic phase and collinear antiferromagnetic order. From a detailed temperature-dependence study, we identify the electronic response to the nematic phase in an orbital-dependent band shift that strictly follows the rotational symmetry of the lattice and disappears when the system restores C_{4} symmetry in the low temperature phase. In addition, we report the observation of a distinct electronic reconstruction that cannot be explained by the known electronic orders in the system.

8.
Neurogastroenterol Motil ; 30(10): e13385, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29971854

RESUMO

BACKGROUND: Postoperative ileus (POI) is abdominal surgery-induced impaired gastrointestinal (GI) motility. We aimed to investigate the effects of DA-9701, a prokinetic agent formulated from Pharbitis Semen and Corydalis tuber, likely mediated via corticotrophin-releasing factor (CRF) pathways, in a POI model. METHODS: A laparotomy with cecal manipulation was performed to induce POI in guinea pigs. GI transit was measured based on charcoal migration after intragastric administration of DA-9701 1, 3, and 10 mg kg-1 . CRF1 receptor antagonist, CP-154 526 (subcutaneous) or agonist, human/rat (h/r) CRF (intraperitoneal) was injected. Then, plasma adrenocorticotropic hormone (ACTH) levels were measured, and the average intensity of the CRF expression was analyzed in the proximal colon and hypothalamus, and c-Fos in the hypothalamus. KEY RESULTS: DA-9701 significantly increased delayed GI transit in POI in a dose-dependent manner and decreased plasma ACTH levels at 10 mg kg-1 . CP-154 526 significantly decreased plasma ACTH levels but was not as effective on GI transit as DA-9701 was. h/r CRF did not significantly affect GI transit and plasma ACTH levels. No significant difference was observed in GI transit and plasma ACTH levels in both groups administered DA-9701 with h/r CRF and h/r CRF alone. CRF expression in the proximal colon decreased after DA-9701 administration, but not significantly, compared with levels in POI alone. However, CRF expression in the hypothalamus was significantly lower in the DA-9701-pretreated POI than in the untreated POI. CONCLUSIONS AND INFERENCES: The DA-9701-induced improvement in GI transit and inhibition of plasma ACTH levels was mediated by the central CRF pathway.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Trânsito Gastrointestinal/efeitos dos fármacos , Íleus/metabolismo , Preparações de Plantas/farmacologia , Complicações Pós-Operatórias/metabolismo , Animais , Modelos Animais de Doenças , Cobaias , Íleus/fisiopatologia , Laparotomia/efeitos adversos , Masculino , Complicações Pós-Operatórias/fisiopatologia
9.
Saudi Med J ; 39(2): 137-141, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29436561

RESUMO

OBJECTIVES: To investigate the presence of Legionella spp in cooling tower water. Legionella proliferation in cooling tower water has serious public health implications as it can be transmitted to humans via aerosols and cause Legionnaires' disease. METHODS: Samples of cooling tower water were collected from King Fahd Hospital of the University (KFHU) (Imam Abdulrahman Bin Faisal University, 2015/2016). The water samples were analyzed by a standard Legionella culture method, real-time polymerase chain reaction (RT-PCR), and 16S rRNA next-generation sequencing. In addition, the bacterial community composition was evaluated. RESULTS: All samples were negative by conventional Legionella culture. In contrast, all water samples yielded positive results by real-time PCR (105 to 106 GU/L). The results of 16S rRNA next generation sequencing showed high similarity and reproducibility among the water samples. The majority of sequences were Alpha-, Beta-, and Gamma-proteobacteria, and Legionella was the predominant genus. The hydrogen-oxidizing gram-negative bacterium Hydrogenophaga was present at high abundance, indicating high metabolic activity. Sphingopyxis, which is known for its resistance to antimicrobials and as a pioneer in biofilm formation, was also detected. CONCLUSION: Our findings indicate that monitoring of Legionella in cooling tower water would be enhanced by use of both conventional culturing and molecular methods.


Assuntos
Carga Bacteriana , DNA Bacteriano/análise , Sequenciamento de Nucleotídeos em Larga Escala , Legionella/isolamento & purificação , RNA Ribossômico 16S/análise , Reação em Cadeia da Polimerase em Tempo Real , Comamonadaceae/genética , Comamonadaceae/isolamento & purificação , Legionella/genética , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Microbiologia da Água
10.
Science ; 357(6346): 71-75, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28684521

RESUMO

The interactions that lead to the emergence of superconductivity in iron-based materials remain a subject of debate. It has been suggested that electron-electron correlations enhance electron-phonon coupling in iron selenide (FeSe) and related pnictides, but direct experimental verification has been lacking. Here we show that the electron-phonon coupling strength in FeSe can be quantified by combining two time-domain experiments into a "coherent lock-in" measurement in the terahertz regime. X-ray diffraction tracks the light-induced femtosecond coherent lattice motion at a single phonon frequency, and photoemission monitors the subsequent coherent changes in the electronic band structure. Comparison with theory reveals a strong enhancement of the coupling strength in FeSe owing to correlation effects. Given that the electron-phonon coupling affects superconductivity exponentially, this enhancement highlights the importance of the cooperative interplay between electron-electron and electron-phonon interactions.

11.
Scott Med J ; 62(2): 58-62, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28606006

RESUMO

Conducting a literature search can be a daunting prospect if you have not done it before. This article aims to provide a beginner's guide to searching the medical education literature, by describing how to construct an effective search strategy, the resources that are available and the basics of how searching works.


Assuntos
Educação Médica/métodos , Armazenamento e Recuperação da Informação/métodos , Literatura , Humanos , Ferramenta de Busca
12.
Neurogastroenterol Motil ; 29(10): 1-6, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28516458

RESUMO

BACKGROUND: Postoperative ileus (POI) is a transient gastrointestinal (GI) dysmotility that commonly develops after abdominal surgery. YH12852, a novel, potent and highly selective 5-hydroxytryptamine 4 (5-HT4 ) receptor agonist, has been shown to improve both upper and lower GI motility in various animal studies and may have applications for the treatment of POI. Here, we investigated the effects and mechanism of action of YH12852 in a guinea pig model of POI to explore its therapeutic potential. METHODS: The guinea pig model of POI was created by laparotomy, evisceration, and gentle manipulation of the cecum for 60 seconds, followed by closure with sutures under anesthesia. Group 1 received an oral administration of vehicle or YH12852 (1, 3, 10 or 30 mg/kg) only, while POI Group 2 was intraperitoneally pretreated with vehicle or 5-HT4 receptor antagonist GR113808 (10 mg/kg) prior to oral dosing of vehicle or YH12852 (3 or 10 mg/kg). Upper GI transit was evaluated by assessing the migration of a charcoal mixture in the small intestine, while lower GI transit was assessed via measurement of fecal pellet output (FPO). KEY RESULTS: YH12852 significantly accelerated upper and lower GI transit at the doses of 3, 10, and 30 mg/kg and reached its maximal effect at 10 mg/kg. These effects were significantly blocked by pretreatment of GR113808 10 mg/kg. CONCLUSION AND INFERENCES: Oral administration of YH12852 significantly accelerates and restores delayed upper and lower GI transit in a guinea pig model of POI. This drug may serve as a useful candidate for the treatment of postoperative ileus.


Assuntos
Motilidade Gastrointestinal/efeitos dos fármacos , Íleus , Pirimidinas/farmacologia , Agonistas do Receptor 5-HT4 de Serotonina/farmacologia , Animais , Modelos Animais de Doenças , Cobaias , Masculino , Complicações Pós-Operatórias
13.
Artigo em Inglês | MEDLINE | ID: mdl-28417537

RESUMO

BACKGROUND: Methane has been associated with constipation-predominant irritable bowel syndrome, slowing intestinal transit time by augmenting contractile activity. However, the precise mechanism underlying this effect remains unclear. Therefore, we investigated the mechanisms underlying the effect of methane on contractile activity, and whether such effects are mediated by nerve impulses or muscular contraction. METHODS: We connected guinea pig ileal muscle strips to a force/tension transducer and measured amplitudes of contraction in response to electrical field stimulation (EFS; 1, 2, 8, 16 Hz) following methane infusion in the presence of tetradotoxin (TTX), atropine, guanethidine, or GR 113808. We then performed calcium imaging using Oregon Green 488 BAPTA-1 AM in order to visualize changes in calcium fluorescence in response to EFS following methane infusion in the presence of TTX, atropine, or a high K+ solution. KEY RESULTS: Methane significantly increased amplitudes of contraction (P<.05), while treatment with TTX abolished such contraction. Methane-induced increases in amplitude were inhibited when lower-frequency (1, 2 Hz) EFS was applied following atropine infusion (P<.05). Neither guanethidine nor GR 113808 significantly altered contraction amplitudes. Methane significantly increased calcium fluorescence, while this increase was attenuated following atropine infusion (P<.05). Although calcium fluorescence was increased by the high K+ solution under pretreatment with TTX, the intensity of fluorescence remained unchanged after methane infusion. CONCLUSIONS AND INFERENCES: The actions of methane on the intestine are influenced by the cholinergic pathway of the enteric nervous system. Our findings support the classification of methane as a gasotransmitter.


Assuntos
Sistema Nervoso Entérico/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Íleo/efeitos dos fármacos , Metano/toxicidade , Contração Muscular/efeitos dos fármacos , Animais , Cobaias , Masculino , Músculo Liso/efeitos dos fármacos , Técnicas de Cultura de Órgãos
14.
Nat Commun ; 8: 13917, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28067228

RESUMO

The study of photoexcited strongly correlated materials is attracting growing interest since their rich phase diagram often translates into an equally rich out-of-equilibrium behaviour. With femtosecond optical pulses, electronic and lattice degrees of freedom can be transiently decoupled, giving the opportunity of stabilizing new states inaccessible by quasi-adiabatic pathways. Here we show that the prototype Mott-Hubbard material V2O3 presents a transient non-thermal phase developing immediately after ultrafast photoexcitation and lasting few picoseconds. For both the insulating and the metallic phase, the formation of the transient configuration is triggered by the excitation of electrons into the bonding a1g orbital, and is then stabilized by a lattice distortion characterized by a hardening of the A1g coherent phonon, in stark contrast with the softening observed upon heating. Our results show the importance of selective electron-lattice interplay for the ultrafast control of material parameters, and are relevant for the optical manipulation of strongly correlated systems.

15.
Sci Rep ; 6: 37910, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27897228

RESUMO

Charge density wave (CDW) formation, a key physics issue for materials, arises from interactions among electrons and phonons that can also lead to superconductivity and other competing or entangled phases. The prototypical system TiSe2, with a particularly simple (2 × 2 × 2) transition and no Kohn anomalies caused by electron-phonon coupling, is a fascinating but unsolved case after decades of research. Our angle-resolved photoemission measurements of the band structure as a function of temperature, aided by first-principles calculations, reveal a hitherto undetected but crucial feature: a (2 × 2) electronic order in each layer sets in at ~232 K before the widely recognized three-dimensional structural order at ~205 K. The dimensional crossover, likely a generic feature of such layered materials, involves renormalization of different band gaps in two stages.

16.
Nat Commun ; 7: 12924, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27671444

RESUMO

Topological quantum materials represent a new class of matter with both exotic physical phenomena and novel application potentials. Many Heusler compounds, which exhibit rich emergent properties such as unusual magnetism, superconductivity and heavy fermion behaviour, have been predicted to host non-trivial topological electronic structures. The coexistence of topological order and other unusual properties makes Heusler materials ideal platform to search for new topological quantum phases (such as quantum anomalous Hall insulator and topological superconductor). By carrying out angle-resolved photoemission spectroscopy and ab initio calculations on rare-earth half-Heusler compounds LnPtBi (Ln=Lu, Y), we directly observe the unusual topological surface states on these materials, establishing them as first members with non-trivial topological electronic structure in this class of materials. Moreover, as LnPtBi compounds are non-centrosymmetric superconductors, our discovery further highlights them as promising candidates of topological superconductors.

17.
Nano Lett ; 16(10): 6331-6336, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27648493

RESUMO

Charge density wave (CDW) formation in solids is a critical phenomenon involving the collective reorganization of the electrons and atoms in the system into a wave structure, and it is expected to be sensitive to the geometric constraint of the system at the nanoscale. Here, we study the CDW transition in TiSe2, a quasi-two-dimensional layered material, to determine the effects of quantum confinement and changing dimensions in films ranging from a single layer to multilayers. Of key interest is the characteristic length scale for the transformation from a two-dimensional case to the three-dimensional limit. Angle-resolved photoemission spectroscopy (ARPES) measurements of films with thicknesses up to six layers reveal substantial variations in the energy structure of discrete quantum well states; however, the temperature-dependent band gap renormalization converges at just three layers. The results indicate a layer-dependent mixture of two transition temperatures and a very-short-range CDW interaction within a three-dimensional framework.

18.
J Clin Neurosci ; 32: 139-41, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27320374

RESUMO

We describe a patient with neuro-Behçets disease (NBD) that presented with symptoms of raised intracranial pressure including papilloedema. MRI revealed tumour-like lesions which, on biopsy, confirmed an active vasculitis. Treatment was commenced with prednisone and cyclophosphamide which proved unsuccessful with enlargement of the cerebral mass lesions. Infliximab and mycophenolate were trialled also without benefit. The patient required ventriculoperitoneal shunts to relieve the symptoms of hydrocephalus. Rituximab was then commenced with significant symptomatic and imaging improvement. The case is unique, in our experience, in the need for shunting to relieve the symptoms of hydrocephalus related to vasculitis.


Assuntos
Síndrome de Behçet/diagnóstico , Encéfalo/diagnóstico por imagem , Imunossupressores/uso terapêutico , Papiledema/etiologia , Rituximab/uso terapêutico , Adulto , Síndrome de Behçet/complicações , Síndrome de Behçet/tratamento farmacológico , Ciclofosfamida/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Infliximab/uso terapêutico , Imagem por Ressonância Magnética/métodos , Ácido Micofenólico/uso terapêutico , Papiledema/tratamento farmacológico , Prednisona/uso terapêutico , Resultado do Tratamento
19.
Biosens Bioelectron ; 80: 161-170, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26827146

RESUMO

Interactions of bacteria with target molecules (e.g. antibiotics) or other microorganisms are of growing interest. The first barrier for targeting gram-negative bacteria is layer of a Lipopolysaccharides (LPS). Liquid crystal (LC) based sensors covered with LPS monolayers, as presented in this study, offer a simple model to study and make use of this type of interface for detection and screening. This work describes in detail the production and application of such sensors based on three different LPS that have been investigated regarding their potential to serve as sensing layer to detect bacteria. The LPS O127:B8 in combination with a LC based sensor was identified to be most useful as biomimetic sensing surface. This LPS/LC combination interacts with three different bacteria species, one gram-positive and two gram-negative species, allowing the detection of bacterial presence regardless from their viability. It could be shown that even very low bacterial cell numbers (minimum 500 cell ml(-1)) could be detected within minutes (maximum 15 min). The readout mechanism is the adsorption of bacterial entities on surface bond LPS molecules with the LC serving as an optical amplifier.


Assuntos
Antibacterianos/farmacologia , Técnicas Biossensoriais , Bactérias Gram-Negativas/isolamento & purificação , Cristais Líquidos/química , Adsorção , Antibacterianos/química , Bactérias Gram-Negativas/química , Bactérias Gram-Negativas/efeitos dos fármacos , Lipopolissacarídeos/química , Fenômenos Ópticos
20.
Artigo em Inglês | MEDLINE | ID: mdl-26312738

RESUMO

A new UV-Visible spectroscopic method assisted with microwave for the determination of glucose in pharmaceutical formulations was developed. In this study glucose solutions were oxidized by ammonium molybdate in the presence of microwave energy and reacted with aniline to produce a colored solution. Optimum conditions of the reaction including wavelength, temperature, and pH of the medium and relative concentration ratio of the reactants were investigated. It was found that the optimal wavelength for the reaction is 610 nm, the optimal reaction time is 80s, the optimal reaction temperature is 160°C, the optimal reaction pH is 4, and the optimal concentration ratio aniline/ammonium molybdate solution was found to be 1:1. The limits of detection and quantification of the method are 0.82 and 2.75 ppm for glucose solution, respectively. The use of microwaves improved the speed of the method while the use of aniline improved the sensitivity of the method by shifting the wavelength.


Assuntos
Glucose/análise , Micro-Ondas , Espectrofotometria Ultravioleta/métodos , Compostos de Anilina/análise , Química Farmacêutica , Concentração de Íons de Hidrogênio , Limite de Detecção , Molibdênio/análise , Soluções , Temperatura , Fatores de Tempo
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