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1.
Discov Nano ; 18(1): 148, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047966

RESUMO

Tuning the electronic properties of transition metals using pyrophosphate (P2O7) ligand moieties can be a promising approach to improving the electrochemical performance of water electrolyzers and supercapacitors, although such a material's configuration is rarely exposed. Herein, we grow NiP2O7, CoP2O7, and FeP2O7 nanoparticles on conductive Ni-foam using a hydrothermal procedure. The results indicated that, among all the prepared samples, FeP2O7 exhibited outstanding oxygen evolution reaction and hydrogen evolution reaction with the least overpotential of 220 and 241 mV to draw a current density of 10 mA/cm2. Theoretical studies indicate that the optimal electronic coupling of the Fe site with pyrophosphate enhances the overall electronic properties of FeP2O7, thereby enhancing its electrochemical performance in water splitting. Further investigation of these materials found that NiP2O7 had the highest specific capacitance and remarkable cycle stability due to its high crystallinity as compared to FeP2O7, having a higher percentage composition of Ni on the Ni-foam, which allows more Ni to convert into its oxidation states and come back to its original oxidation state during supercapacitor testing. This work shows how to use pyrophosphate moieties to fabricate non-noble metal-based electrode materials to achieve good performance in electrocatalytic splitting water and supercapacitors.

2.
Discov Nano ; 18(1): 59, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37382728

RESUMO

The major center of attraction in renewable energy technology is the designing of an efficient material for both electrocatalytic and supercapacitor (SC) applications. Herein, we report the simple hydrothermal method to synthesize cobalt-iron-based nanocomposites followed by sulfurization and phosphorization. The crystallinity of nanocomposites has been confirmed using X-ray diffraction, where crystalline nature improves from as-prepared to sulfurized to phosphorized. The as-synthesized CoFe-nanocomposite requires 263 mV overpotential for oxygen evolution reaction (OER) to reach a current density of 10 mA/cm2 whereas the phosphorized requires 240 mV to reach 10 mA/cm2. The hydrogen evolution reaction (HER) for CoFe-nanocomposite exhibits 208 mV overpotential at 10 mA/cm2. Moreover, the results improved after phosphorization showing 186 mV to reach 10 mA/cm2. The specific capacitance (Csp) of as-synthesized nanocomposite is 120 F/g at 1 A/g, along with a power density of 3752 W/kg and a maximum energy density of 4.3 Wh/kg. Furthermore, the phosphorized nanocomposite shows the best performance by exhibiting 252 F/g at 1 A/g and the highest power and energy density of 4.2 kW/kg and 10.1 Wh/kg. This shows that the results get improved more than twice. The 97% capacitance retention after 5000 cycles shows cyclic stability of phosphorized CoFe. Our research thus offers cost-effective and highly efficient material for energy production and storage applications.

3.
Nanomaterials (Basel) ; 12(23)2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36500743

RESUMO

The green, sustainable, and inexpensive creation of novel materials, primarily nanoparticles, with effective energy-storing properties, is key to addressing both the rising demand for energy storage and the mounting environmental concerns throughout the world. Here, an orange peel extract is used to make cobalt oxide nanoparticles from cobalt nitrate hexahydrate. The orange peel extract has Citrus reticulata, which is a key biological component that acts as a ligand and a reducing agent during the formation of nanoparticles. Additionally, the same nanoparticles were also obtained from various precursors for phase and electrochemical behavior comparisons. The prepared Co-nanoparticles were also sulfurized and phosphorized to enhance the electrochemical properties. The synthesized samples were characterized using scanning electron microscopic and X-ray diffraction techniques. The cobalt oxide nanoparticle showed a specific capacitance of 90 F/g at 1 A/g, whereas the cobalt sulfide and phosphide samples delivered an improved specific capacitance of 98 F/g and 185 F/g at 1 A/g. The phosphide-based nanoparticles offer more than 85% capacitance retention after 5000 cycles. This study offers a green strategy to prepare nanostructured materials for energy applications.

4.
J Oral Maxillofac Pathol ; 26(1): 77-81, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571313

RESUMO

Background: Bacteria and their products involved in periodontitis evoke an immunoinflammatory response in the host tissue. Inflammatory diseases, such as periodontitis, are often not just a local event, but may have systemic ramifications, including elevations in the numbers of circulating leukocytes, acute-phase proteins and oxidative stress markers. It is now emerging that also erythrocytes are affected by chronic inflammatory diseases. This phenomenon, named "anemia of inflammation," is not caused by marrow deficiencies or other diseases. The present study aimed to assess whether there was any relation between chronic periodontitis and hematological parameters. Materials and Methods: A total of 80 patients were included in the study and were divided into the healthy and periodontitis groups. Blood sample was obtained from each participant for hematological analysis of leukocytes, erythrocytes, platelets, red blood cell (RBC) distribution width (RDW), mean corpuscular volume (MCV), platelet count and neutrophil-leukocyte ratio (NLR). Further, the values were gathered and subjected to statistical analysis. Unpaired t-test was performed to assess the statistical significance between the groups and P < 0.05 and < 0.001 were considered to be statistically significant. Results: Results show statistically significant difference seen in leukocytes, lymphocytes, RDW, MCV, platelet count and NLR which was higher in patients with periodontitis, all other parameters are nonsignificant. Conclusion: Thus, within limitations, it can be concluded that increased levels of leukocytes, lymphocytes, RDW, MCV, platelet count and NLR depict the inflammatory state and destructive nature of periodontitis.

5.
Int J Pharm Investig ; 5(4): 234-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26682194

RESUMO

INTRODUCTION: The work was aimed to develop an enteric-coated hydroxypropyl methylcellulose (HPMC) capsules (ECHC) plugged with 5-fluorouracil (5-FU)-loaded microsponges in combination with calcium pectinate beads. MATERIALS AND METHODS: The modified quasi-emulsion solvent diffusion method was used to prepare microsponges. A 3(2) factorial design was employed to study the formulation and the effects of independent variables (volume of organic solvent and Eudragit-RS100 content) on dependent variables (particle size, %entrapment efficiency, and %cumulative drug release). The optimized microsponge (F4) was characterized by scanning electron microscopy, powder X-ray diffraction, and thermogravimetric analysis. F4 was plugged along with the calcium pectinate beads in HPMC capsules coated with enteric polymer Eudragit-L100 (Ed-L100) and/or Eudragit-S100 (Ed-S100) in different proportions. An in vitro release study of ECHC was performed in simulated gastric fluid for 2 h, followed by simulated intestinal fluid for next 6 h and then in simulated colonic fluid (in the presence and absence of pectinase enzyme for further 16 h). The optimized formulation was subjected to in vivo roentgenographic and pharmacokinetic studies in New Zealand white rabbits to analyze the in vivo behavior of the developed colon-targeted capsules. RESULTS: Drug release was retarded on coating with Ed-S100 in comparison to a blend of Ed-S100:Ed-L100 coating. The percentage of 5-FU released at the end of 24 h from ECHC3 was 97.83 ± 0.12% in the presence of pectinase whereas in the control study, it was 40.08 ± 0.02%. CONCLUSION: Thus, enteric-coated HPMC capsules plugged with 5-FU-loaded microsponges and calcium pectinate beads proved to be a promising dosage form for colon targeting.

6.
Expert Opin Drug Deliv ; 9(7): 863-78, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22663167

RESUMO

INTRODUCTION: Microparticulate drug delivery systems have, due to their advantages, guided researchers across the globe to explore them as drug carriers. This has, sequentially, led to the development of microsponges in 1988. These porous microspheres were exclusively designed for chronotherapeutic topical drug delivery but attempts to utilize them for oral, pulmonary and parenteral drug delivery were also made. Researchers have extensively studied their properties and characteristics affecting the drug release and loading. Various advances were made with this carrier particle resulting in the development of various novel development techniques and carrier particles. AREAS COVERED: This review deals with the considerations of the drug material to be entrapped in microsponges, pharmaceutical considerations for fabrication of microsponges, their potential for oral drug delivery, clinical perspectives and also provides an insight on the recent advances made in this field and future prospect. EXPERT OPINION: Clinical studies show that these carriers can increase drug efficacy. Due to their potential advantages over other carrier particles, microsponges form a prospective platform for the oral delivery of pharmaceuticals and biopharmaceuticals. Although these carriers have several advantages, they too possess some drawbacks which limit their commercialization for oral application.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Microesferas , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Humanos , Porosidade
7.
Int J Pharm ; 427(2): 153-62, 2012 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-22306039

RESUMO

The work was aimed at developing calcium-pectinate matrix tablet for colon-targeted delivery of meloxicam (MLX) microsponges. Modified quassi-emulsion solvent diffusion method was used to formulate microsponges (MS), based on 3(2) full factorial design. The effects of volume of dichloromethane and EudragitRS100 content (independent variables) were determined on the particle size, entrapment efficiency and %cumulative drug release of MS1-MS9. The optimized formulation, MS5 (d(mean)=44.47 µm, %EE=98.73, %CDR=97.32 and followed zero order release) was developed into colon-targeted matrix tablet using calcium pectinate as the matrix. The optimized colon-targeted tablet (MS5T2) shielded MLX loaded microsponges in gastrointestinal region and selectively delivered them to colon, as vizualized by vivo fluoroscopy in rabbits. The pharmacokinetic evaluation of MS5T2 in rabbits, revealed appearance of drug appeared in plasma after a lag time of 7h; a t(max) of 30 h with Fr=61.047%, thus presenting a formulation suitable for targeted colonic delivery. CLSM studies provided an evidence for colonic luminal retentive ability of microsponges at the end of 8h upon oral administration of MS5T2. Thus calcium pectinate matrix tablet loaded with MLX microsponges was developed as a promising system for the colon-specific delivery that has potential for use as an adjuvant therapy for colorectal cancer.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Colo/metabolismo , Tiazinas/administração & dosagem , Tiazóis/administração & dosagem , Algoritmos , Animais , Anti-Inflamatórios não Esteroides/farmacocinética , Soluções Tampão , Química Farmacêutica , Difusão , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Emulsões , Excipientes , Fluoroscopia , Meloxicam , Tamanho da Partícula , Pectinas , Coelhos , Reprodutibilidade dos Testes , Reologia , Solubilidade , Solventes , Propriedades de Superfície , Comprimidos , Tiazinas/farmacocinética , Tiazóis/farmacocinética
8.
Rev Recent Clin Trials ; 7(2): 158-64; discussion 164-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22353199

RESUMO

This drug utilization or prescription-monitoring study was conducted to evaluate the drug-prescribing trend of anti-asthmatic drugs in various hospitals (health care centre) of Shamli, (Prabuddha Nagar, Uttar Pradesh, India). The study was conducted in three famous hospitals of Shamli on three hundred thirty (330) patients, using a developed prescription auditing Performa. Data was recorded from the co-operating patients, attending the outpatient department using a chance random sample method for six months by interviewing and information was filled in the performa. The collected data was studied statistically for determining the most prominently prescribed medication for the treatment. The collected information suggested that ß-agonist were the most frequently prescribed anti-asthmatic drugs followed by corticosteroids, Methylxanthine, anti-histaminics and leukotriene antagonist. Also the performed prescription analysis revealed that there is significant difference in the prescriptions for multiple drug therapy (90%) as compared to single drug therapy (10%). Also even after the commercial development of pulmonary targeted systems, oral dosage form like tablets (54.93%) were preferred over inhalation (31.69%). Thus, it can be concluded that the present prescribing pattern of antiasthmatics in Shamli does not completely meet standard guidelines for the asthma treatment. Hence there is a need of awareness amongst the physicians of Shamli so that they can follow the guidelines while treating asthma. Also the patients must be encouraged to use newly developed inhalational drug delivery systems for improving the treatment.


Assuntos
Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Prescrições de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/normas , Padrões de Prática Médica , Administração por Inalação , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Estudos Prospectivos , Adulto Jovem
9.
Recent Pat Drug Deliv Formul ; 5(2): 146-62, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21453249

RESUMO

The eye due to its special attributes is an effortlessly accessible location for topical drug administration. Topical administration not only provides local targeting of drugs but also offers a better control over the systemic delivery. Bioavailability of drugs from ocular dosage forms is dependent to the precorneal loss factors (physiological and anatomical constraints of eye) thus, very small fraction of the drug is absorbed through ocular route. The effective dose of medication administered ophthalmically may be altered by changing the formulation. Various research reports have been documented for ocular drug delivery, both on academic level as well as commercial level resulting in augmented increase in the numbers of patents in this field. The primary objective of the present review is to provide an overview of the ocular drug delivery systems with special emphasis on the intellectual aspects of these systems. This paper also attempts to extend the information on ocular drug delivery systems already existing in the literature by focusing on the update on the patents granted as well as applications published for these systems during the last decade.


Assuntos
Sistemas de Liberação de Medicamentos , Implantes de Medicamento , Oftalmopatias/tratamento farmacológico , Soluções Oftálmicas/administração & dosagem , Patentes como Assunto , Humanos
10.
Braz. j. pharm. sci ; 51(3): 591-605, July-Sept. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-766309

RESUMO

The work was aimed at developing novel enteric coated HPMC capsules (ECHC) plugged with 5 Florouracil (5-FU) loaded Microsponges in combination with calcium pectinate beads. Modified quasi-emulsion solvent diffusion method was used to formulate microsponges based on 32 factorial design and the effects of independent variables (volume of organic solvent and Eudragit RS100 content) on the dependent variables (Particle size, %EE & % CDR) were determined. The optimized microsponges (F4) were characterized by SEM, PXRD, TGA and were plugged along with calcium pectinate beads in HPMC capsules and the HPMC capsules were further coated with enteric polymer Eudragit L 100 (Ed-L100) and/ or Eudrgit S 100 (Ed-S 100) in different proportions. In vitro release study of ECHC was performed in various release media sequentially SGF for 2 h, followed by SIF for the next 6 h and then in SCF (in the presence and absence of pectinase enzyme for further 16 h). Drug release was retarded on coating with EdS-100 in comparison to blend of EdS-100: EdL-100 coating. The percentage of 5-FU released at the end of 24 h from ECHC 3 was 97.83 ± 0.12% in the presence of pectinase whereas in control study it was 40.08 ± 0.02% drug. The optimized formulation was subjected to in vivo Roentgenographic studies in New Zealand white rabbits to analyze the in vivo behavior of the developed colon targeted capsules. Pharmacokinetic studies in New Zealand white rabbits were conducted to determine the extent of systemic exposure provided by the developed formulation in comparison to 5-FU aqueous solutions. Thus, enteric coated HPMC capsules plugged with 5-FU loaded microsponges and calcium pectinate beads proved to be promising dosage form for colon targeted drug delivery to treat colorectal cancer.


O trabalho teve como objetivo o desenvolvimento de novas cápsulas com revestimento entérico HPMC (ECHC) conectadas com microesponjas carregadas com fluoruracila (5-FU) em combinação com grânuos de pectinato de cálcio. O método de difusão de solvente modificado quasi-emulsão foi usado para formular microesponjas com base no planejamento fatorial 32 e determinaram-se os efeitos das variáveis independentes (volume de solvente orgânico e conteúdo Eudragit RS100) sobre as variáveis dependentes (tamanho de partícula, EE% e % CDR). As microesponjas otimizadas (F4) foram caracterizadas por SEM, PXRD, TGA e ligadas aos grânulos de pectinato de cálcio em cápsulas de HPMC e estas foram, ainda, revestidas com polímero entérico Eudragit L 100 (Ed-L100) e/ou Eudrgit S 100 (Ed S 100) em diferentes proporções. No estudo de liberação in vitro de ECHC foi realizada em vários meios de liberação sequencial SGF durante 2 h, seguido de SIF para as próximas 6 h, e, em seguida, em SCF (na presença e na ausência de enzima pectinase por mais 16 h). A liberação do fármaco foi retardada em revestimento com a EDS-100, em comparação com mistura de EDS-100: EDL-100, de revestimento. O percentual de 5-FU liberado de ECHC 3 ao final de 24 h foi 97,83 ± 0,12% em presença de pectinase, enquanto que para o controle foi de 40,08 ± 0,02% do fármaco. A formulação otimizada foi submetida a estudos Roentgenográficos in vivo, em coelhos brancos Nova Zelândia, para analisar o comportamento das cápsulas desenvolvidas direcionadas ao cólon. Os estudos de farmacocinética em coelhos brancos da Nova Zelândia foram conduzidos para determinar a extensão da exposição sistêmica propiciada pela formulação desenvolvida, em comparação com solução aquosa de 5-FU. Assim, cápsulas entéricas de HPMC revestidas e conectadas com microesponjas carregadas com 5-FU e grânulos de pectinato de cálcio se mostraram promissoras como formulação para liberação do fármaco no cólon no tratamento do câncer colorretal.


Assuntos
Coelhos , Comprimidos com Revestimento Entérico/análise , Cápsulas/farmacocinética , Neoplasias do Colo/classificação , Derivados da Hipromelose , Química Farmacêutica , Fluoruracila/análise
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