Solid dispersions have been efficient in improving the dissolution rate and bioavailability of hydrophobic drugs. The aim of the present study was enhancement of the dissolution profile of ...Spironolactone using solid dispersion.
Spironolactone solid dispersions (1:1, 1:2 and 2:1 drug: carrier weight ratio) were prepared by polyethylene glycol (PEG) 6000 as a carrier by hot melt method. The influence of several amounts of Tween 20, 60, and 80 were also studied. The dissolution profile was evaluated by USP Apparatus II.
The results showed that solid dispersions were efficacious to enhance the dissolution rate of Spironolactone in water; and the procedure indicated that there was an increase in dissolution rate for solid dispersions containing the surfactant Tweens. The solid dispersions were evaluated using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) studies; and the results showed no complex formation or change in crystal shape of drug.
It is concluded that solid dispersion technique can be successfully used for improvement of dissolution of Spironolactone.
Gliclazide is a second-generation hypoglycemic sulfonylurea, which is useful in the treatment of non-insulin-dependent diabetes mellitus. It has low bioavailability because of its limited water ...solubility and slow dissolution rate. In this study, solid dispersions of gliclazide were prepared by solvent method. Drug and carriers weight ratio were 1:9; 2:8; 3:7; 4:6; and 5:5. The weight ratio of carriers (polyvinyl pyrrolidone K-30 and polyethylene glycol 6000) was 1:1. The properties of solid dispersions were evaluated using scanning electron microscopy (SEM), Fourier-transform infra red (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and solubility and dissolution studies. SEM result showed that gliclazide was highly dispersed and was present as amorphous state in the solid dispersions. The FTIR spectroscopy showed no chemical interaction between gliclazide and carriers. DSC studies indicated melting point of gliclazide was decreased. The XRD studies indicated that crystallinity degree of gliclazide was decreased. Rate of dissolution and solubility of solid dispersions was increased than pure gliclazide (F < 0.05).
Mn0.25Fe2.75O4 nanoparticles have been successfully synthesized using a coprecipitation method. PEG 6000 polymer was added on the synthesis of Mn0.25Fe2.75O4 which aimed at decreasing and preventing ...the emergence of aggregation between particles. The characterization of the phase structure, absorption of functional groups, and distribution of Mn0.25Fe2.75O4-PEG 6000 nanoparticles have been successfully performed using the instruments of XRD, FTIR, and Small Angel X-Ray Scatterring (SAXS) respectively. XRD characterization results showed that the phase structure formed was in the form of magnetite and corresponded to the Inorganic Crystal Structure Database (ICSD) number 9013529. The bond of Fe-O and Mn-O consecutively on the wave numbers of 430 and 482 cm−1 which were the representation of Mn0.25Fe2.75O4 material have been successfully confirmed through the characterization using FTIR, meanwhile the stretching vibrating on the wave numbers of 1251, 1352, 1472, and 1629 cm−1 for functional groups C-H is the representation of PEG template which has the chemical structure of -OH-CH2-CH2-n OH. SAXS characterization showed that the primary and secondary particle sizes from the Mn0,25Fe2,75O4-PEG 6000 nanoparticle were 3.08 and 11.4 nm respectively. The value is the optimum results of the PEG 6000 template influence on the synthesize of Mn0.25Fe2.75O4-PEG 6000 nanoparticles which are potential to be a raw material of magnetic fluid and gel on hyperthermia therapy.
Species that can germinate under low water potential are likely to have greater utility for fodder production and restoration in arid habitats. We investigated seed germination response of four ...native grass species (Panicum acuminatum, Panicum turgidum, Pennisetum divisum and Polypogon monspeliensis) to five osmotic potentials (0, −0.3, −0.6, −0.9 and −1.2 MPa) using polyethylene glycol‐6000 and two light treatments (0, 12 h light per day). All the studied species exhibited high germination (> 77%) at ψ = 0 MPa except P. turgidum (42%). Polypogon monspeliensis seeds did not show any significant reduction in germination from ψ = 0 to −0.3 MPa (90–83%), but all other species did, averaging from 75.8 to 60.5%. At ψ = −0.6 MPa seed germination was reduced to around 20%. Germination of most species was unaffected by light, but P. divisum seeds that germinated in darkness were more tolerant to water deficit. Reduction of water potential to −0.3 MPa inhibited the germination timing for P. acuminatum (ca 1.69 days difference to 50% germination t50), P. divisum (ca 1.56 day) and P. monspeliensis (ca 1.14 days). Germination of P. acuminatum and P. monspeliensis were similar after stressful exposure to all osmotic potentials, while for P. divisum there was reduced germination (85% at −0.6 MPa to 58% −1.2 MPa), indicating a dormancy induction. Tolerance to low water potentials, and response after release from these low potentials, indicates the species are adapted to survive in drier environments.
BackgroundCutleaf geranium ( Geranium dissectum L) is a weed found in cereals and grasslands. Knowledge about the germination response of weeds under various environmental conditions is critical for ...their effective management, whereas such study has not been carried out thoroughly on this species.ObjectiveThis study was carried out to investigate the effect of some environmental factors on seed germination and emergence of cutleaf geranium.MethodsThe seeds were subjected to various environmental factors including water potentials, salinity, pH, high temperatures, burial depth and flooding at the temperature resulting in the highest germination (10 °C). All experiments were carried out twice, which were done consecutively.ResultsGermination percentage was halved at a water potential of -0.6 MPa, and no germination was observed at -2 MPa. Geranium dissectum seeds had negligible germination at 200 mM NaCl concentration. Seeds germinated over a pH range of 5-8, with the highest germination at pH between 6 and 7. Germination of this species reached from 85.0% after treatment at 80 °C but no seeds germinated after exposure to 120 °C. Maximum emergence was estimated 88.8%, which was halved at 2.2 cm depth. No emergence was observed at 4 cm or greater depths. Germination was 88.4% to 0% 15 days after flooding.ConclusionsThis species may not usually be found in areas with poor environmental conditions, and a semi-deep tillage or inclusion of rice in crop rotation may be used to control this weed.
Seed is a fundamental tool to carry out breeding processes and for the propagation of the crops; however, seed propagation generally has low and irregular germination. Passion fruit (Passiflora) ...species are economically important for Ecuador, which is the main exporter of passion fruit concentrate in Latin America. Ecuadorian farmers propagate new plants by seeds to establish new passion fruit orchards or to extend their cultivated area. The objective of this research was to determine the differences in germination and seedling development with the application of priming methods in five genotypes of passion fruit belonging to three different taxa that are of commercial use in Ecuador. The genotypes used were: INIAP 2009 and P10 (P. edulis f. flavicarpa), Gulupa (P. edulis f. edulis), and local germplasms POR1 (P. edulis f. flavicarpa) and PICH1 (P. maliformis). The priming methods were: water (control), hydrogen peroxide at 15%, potassium nitrate at 1%, PEG 6000 at −1.2 MPa, and gibberellic acid at 500 ppm. The results showed that there was a genotype-response depending on the priming method. Nevertheless, Polietilenoglicol (PEG 6000) could be considered as a promising method to encourage seed germination and promote seedling growth in the Passiflora species. More research regarding the use of this compound has to be carried out in order to determine in depth the physiological processes related to its functions to improve seed germination as well as production of vigorous seedlings.
The aim of this study was to evaluate the effect of water stress on the germination of Coffea arabica seeds and the growth and development of plants from these seeds. Seeds of the cultivars Bourbon ...Vermelho, Mundo Novo, and BA-10 were placed to germinate in the dark at 30 ºC in the presence and absence of 100 g/L of polyethylene glycol 6000. The water stress applied delayed the beginning of seed germination by seven days in relation to seeds of the control, which had achieved responses of up to 50%, but there were no differences between the treatments at the end of the experiment. Furthermore, the length of the primary root in seeds germinated under water stress was less than in the control treatment, especially for the cultivar Mundo Novo. Plants of the cultivars Bourbon Vermelho and Mundo Novo developed from seeds previously germinated under water stress exhibited reduced height and fewer leaf pairs than those from the control, whereas ‘BA-10’ responded in a similar way in both treatments. Thus, the cultivars Bourbon Vermelho and Mundo Novo were more sensitive to the water stress applied in the germination phase than ‘BA-10’.
Resumo: O objetivo deste estudo foi avaliar o efeito do estresse hídrico na germinação de sementes de Coffea arabica e o crescimento das plantas provenientes destas. Sementes das cultivares Bourbon Vermelho, Mundo Novo e BA-10 foram colocadas para germinar na presença e ausência de 100 g/L de Polietilenoglicol 6000, no escuro, a 30 ºC. O estresse hídrico aplicado atrasou o início da germinação das sementes em sete dias em relação àquelas do controle que tinham atingido respostas de até 50%, porém não houve diferenças entre os tratamentos no final do experimento. Além disto, as sementes germinadas sob estresse hídrico tiveram redução do comprimento da raiz primária em relação àquelas do controle, principalmente, para o Mundo Novo. Plantas das cultivares Bourbon Vermelho e Mundo Novo desenvolvidas a partir das sementes previamente germinadas sob estresse hídrico tiveram redução da altura e do número de pares de folhas em comparação com aquelas provenientes do controle, enquanto a cultivar BA-10 respondeu de forma semelhante nos dois tratamentos. Assim, as cultivares Bourbon Vermelho e Mundo Novo foram mais sensíveis ao estresse hídrico aplicado na fase de germinação que o ‘BA-10’.
Hydrophobic lubricants are commonly used to reduce the frictional forces generated during tableting but impart a hydrophobic film on the surface of the powder or granules. This negatively affects the ...performance properties of the resultant tablets by slowing disintegration and dissolution, which is especially problematic in the case of orally disintegrating tablets. In the present study a comparative evaluation of the lubricant capacity of Compritol® HD5 ATO was performed with commonly used amphiphilic lubricants, sodium stearyl fumarate and PEG 6000. The effect of concentration and mixing time of Compritol® HD5 ATO with the granulation, on material flow properties, tablet ejection force, hardness, disintegration time and rate of dissolution of paracetamol tablets was evaluated. The physical properties of the lubricants such as crystallinity, wettability, thermal behaviour and surface area were also measured. Compritol® HD5 ATO is crystalline, hydrodispersible and thermostable. It reduced the tablet ejection force, the desired hardness range was obtained at significantly lower compression forces and no significant effect of lubricant mixing time and concentration on the hardness and disintegration time of the tablets was observed when compared with Sodium stearyl fumarate and PEG 6000. Compritol® HD5 ATO was found to be an as effective a lubricant for a fast disintegrating paracetamol formulation containing microcrystalline cellulose, lactose and PVP prepared by wet granulation in comparison with sodium stearyl fumarate and PEG 6000.
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