The solubility of pure PAL in distilled water was found to be 1.56 μg/ml indicating poor solubility. The solubility studies showed a linear increase in drug solubility with increased carrier levels. At 0.7% concentration of Plasdone S630, Povidone K25, and Povidone K30, the increase in solubility was 12, 9, and 6 folds, respectively, compared with pure drug (Table 2 and Fig. 1). The increase in solubility in the presence of carrier can probably be explained by increased wettability of PAL. Hydrophilic carriers are known to interact with drug molecules mainly by electrostatic forces and occasionally by other type of forces such as hydrogen bonds [25-28].
Kamal Dua et al (2010) developed the objective of the present investigation was to study the effect of various water soluble carriers like urea, mannitol, PVP and PVP/VA-64 on in vitro dissolution of aceclofenac from solid dispersions. Aceclofenac binary solid dispersions (SD) with different drug loadings were prepared using the melting or fusion method. In vitro dissolution of pure drug, physical mixtures and solid dispersions were carried out. Solid dispersion of aceclofenac with all four carriers (urea, mannitol, PVP and PVP/VA-64) showed considerable increase in the dissolution rate in comparison with physical mixture and pure drug in 0.1 N HCl, pH1.2 and phosphate buffer, pH, 7.4. FT-IR spectroscopy and differential scanning calorimetry studies indicated no interaction between aceclofenac and carriers in solid dispersions in solid state. Dissolution enhancement was attributed to decreased crystallinity of the drug and to the wetting, eutectic formation and solubilizing effect of the carrier from the solid dispersions of aceclofenac. In conclusion, dissolution of aceclofenac can be enhanced by the use of various hydrophilic carriers like urea, mannitol, PVP and PVP/VA-64. 50
117 Read more
The main objective of this study was to investigate the effect of various hydrophilic carriers on the dissolution behavior of aceclofenac. Solid dispersion was prepared using Poly Vinyl Pyrrolidone (PVP), Mannitol or Urea as hydrophilic carriers by kneading and physical mixing methods. The micromeritic properties, Fourier transform infra-red (FTIR) spectroscopy, percentage practical yield, drug content, wettability and in vitro drug releasewere evaluated. The Solid dispersion was prepared in 1:1, 1:3 and 1: 5 weight ratios of the drug to carrier. FTIR studies showed that there was no interaction between the drug and carrier. In vitro release profiles of all Solid dispersions (F1 to F18) were comparatively evaluated and also compred with pure Aceclofenac. Among the Solid dispersions, F15 (1:5) using PVP showed minimal wetting time of 13 seconds and maximum drug
15 Read more
All solid dispersions prepared by kneading method and solvent evaporation method shows increment in solubility as well as drug release profile as compare to physical mixtures with low standard deviation values in percent drug content ensured uniformity of drug content in each batch. The solubility was enhanced from 0.62 mg/ml (plain rifapentine) to 6.34 mg/ml (SP8) by using hydrophilic carrier in solid dispersion formulation by using simple solvent evaporation technique. Figure 4 and 6 shows the in vitro dissolution profiles of rifapentine from SDs containing various ratios of drug to PVP-K30 in which max % drug release was obtained in batch SP8 (93.91±0.22). Figure 5 and 7 shows the in vitro dissolution profiles of rifapentine from SDs containing various ratios of drug to HPMC in which max % drug release was obtained in batch SH8 (90.36±0.22 ). In contrast, the dissolution rate of rifapentine from all PVP-K30 and
So to increase the solubility, dissolution rate and absorption it was aimed to formulate solid dispersion of Nifedipine by incorporating the drug with hydrophilic carriers such as Polyethylene glycol 6000 and Urea. In the present work, four formulations of Nifedipine solid dispersions(F 1 -F 4 ) were prepared using two hydrophilic carriers such as Poly ethylene
Celecoxib is a non-steroidal anti-inflammatory drug. The present study was planned to prepare and evaluate the solid dispersions of Celecoxib. Solid dispersions of Celecoxib were prepared by using various hydrophilic carriers like PVP-K-40, PEG 6000, PEG 4000 and Dextrin in various ratios by melt-in solvent method and solvent evaporation technique. The prepared solid dispersions were subjected to solubility studies (in water, 0.1N HCl and phosphate buffer pH 7.4) and drug content uniformity studies. The in-vitro release studies were carried out with USP type I dissolution apparatus (100 rpm, 37 ± 2 o C) in phosphate buffer pH 7.4 and stability studies were carried out at 40 ± 2 o C and 75± 5% RH. The cumulative amount of drug release at the end of 2 hours of Celecoxib: PVP was 96.86%, Celecoxib: PEG-4000 was 97.06 %, Celecoxib: PEG-6000 was 97.32% and Celecoxib: dextrin was 98.05%. Therefore, it can be concluded that the dissolution rate of poorly soluble drug Celecoxib can be significantly enhanced by formulating it into solid dispersions.
In vitro release study in phosphate buffer pH 6.8 shows that the rate of drug release was faster in case of hydrophilic surfactant (Tween 80), this is due to the hydrophilic nature of surfactant, microspheres prepared using span 80 were expected to release the drug faster than microspheres prepared using Tween 80 due to their smaller particle size. But increased surface area available for drug release was not effective enough as compared to hydrophilic nature of the microspheres. But within the same type of surfactant, increase in surfactant concentration leads to reduced particle size, increase surface area and increased drug release.
12 Read more
In renal dialysis patients, HLA-A*02 was the most frequent allele in both carriers (25.5%) and non-carriers (21.2%) of S. aureus. Allele A*68 was not observed in the carrier group, but the allele was observed six times in the non- carrier group (p = 0.0097). Regarding HLA-B and HLA-DRB1, no allele was shown to be involved in protection against or susceptibility to carriage of S. aureus. In kidney transplant patients, allele A*03 was more frequent in the non-carrier (20.83%) than in the carrier (5.88%) group (p = 0.0486). HLA-B*15 was present in carriers (5.88%) and non-carriers (25%) (p = 0.0179). Regarding class II alleles, DRB1*03 appeared to be related to susceptibility to carriage of S. aureus (p = 0.0319).
To study the scale dependency of discrete droplet formation and stability of dropwise condensation, we quantified the droplet distri- bution for nano- to macroscale droplets during condensation on a vertical flat plate. The experimental setup is described elsewhere (26). Briefly, the sample is cooled to 0.05° ± 0.1°C. Saturated water vapor was sparged from a second water bath of deionized (DI) water at 73° ± 3°C. The resulting condensation area spanned roughly 2.5 cm horizontally and 1 cm vertically and represented the topmost area of a vertical pate. To capture droplet data during all stages of a sweeping period and to ensure statistical significance, we captured one image every 20 s. Figure 3 shows the self-similar nature for both hydrophilic PEGylated and hydrophobic surfaces. On both hydro- phobic (Fig. 3, A and B) and hydrophilic (Fig. 3, C and D, and movie S1) surfaces, all droplets remained as spherical caps and dropwise con- densation ensued without film formation.
lower than that in hydrophilic guidewire group. Further- more, hydrophilic guidewire had more chances advanced into coronary artery and carotid artery due to the inher- ent characteristic of hydrophilic guidewire. Though no adverse events happened in the study, it was a potential change was commonly rare except those accompanied by switchover. Even taking the guidewire exchange into account, the cost in non-hydrophilic group was still lower than that in hydrophilic guidewire group. Further- more, hydrophilic guidewire had more chances advanced into coronary artery and carotid artery due to the inher- osity, which might prolong the fluoroscopy time and procedure time in these patients, but guidewire ex- change was commonly rare except those accompanied by switchover. Even taking the guidewire exchange into account, the cost in non-hydrophilic group was still study. Higher chances of guidewire exchange were ob- served in non-hydrophilic group because of severe tortu- osity, which might prolong the fluoroscopy time and procedure time in these patients, but guidewire ex- change was commonly rare except those accompanied uncomfortable and cause back strain for operators . However, there are some limitations in the present study. Higher chances of guidewire exchange were ob- served in non-hydrophilic group because of severe tortu- osity, which might prolong the fluoroscopy time and patients compared with the right radial approach (RRA) [28-31], nevertheless, leaning over the patient to ma- nipulate catheters through the left radial artery may be uncomfortable and cause back strain for operators . However, there are some limitations in the present it has been reported that for coronary diagnostic proce- dures, left radial approach (LRA) is associated with lower fluoroscopy time and radiation dose adsorbed by patients compared with the right radial approach (RRA) [28-31], nevertheless, leaning over the patient to ma- room setup and familiarity of manipulating the catheter from the right side as in the femoral approach. Although it has been reported that for coronary diagnostic proce- dures, left radial approach (LRA) is associated with lower fluoroscopy time and radiation dose adsorbed by tinely used in clinical practice due to feasibility with room setup and familiarity of manipulating the catheter
SDs were performed include. Incorporation of polymer(Ploxamer F68,Eudragit Epo and HP- betaCD) enhanced the dissolution rate of nimodipine. In addition, the dissolution of the drug is improved. The enhancement of dissolution of drug from drug polymer systems can be ascribed to several factors. The mechanism of dissolution rate improvement from solid dispersion is lack of crystallinity and particle size reduction considered to be important factors for dissolution rate enhancement. mixing of drug with a hydrophilic polymer results in greater wetting and increase surface available for dissolution by reducing interfacial tension between the hydrophilic drug and dissolution media. It was noted that drug polymer system sink immediately, while pure drug keeps floating on the surface for a longer time interval.(12) The dissolution parameters of drug (nimodipine) solid dispersion with various polymers Ploxamerf68,Eudragitepo and HPbetaCD in same concentration of each polymer. The dissolution rate of pure drug is low as 22% of the drug gets dissolved 60min respectively. Solid dispersions formulated with all the polymers exhibited significant improvement in the dissolution parameters of drug. The order of dissolution enhancement with various binary systems was found to be (F-9,6>F-3,1,2>F-4,5,8,7) for nimodipine. The increase in the dissolution rate of the solid mixtures might be due to size reduction and increase in the wettability of the drug molecules in presence of the polymers. Polymers also lowering the surface tension, hence increasing the solubilizing effect.
10 Read more
BRs contain multiple polyhydroxy groups and thus exhibit hydrophilic property. In light of this property, hydrophilic magnetic materials were chosen as sorbents, and a fast and convenient MSPE-ISD method based on hydrophilic interaction was developed for the determin- ation of endogenous BRs in plant tissues. By employing hydrophilic magnetic material as both a microextraction sorbent and “microreactor”, the MSPE-ISD method integrates extraction and derivatization together, which largely simplifies the analytical process. First, BRs were extracted onto the surface of a magnetic sorbent through hydrophilic interaction in the acetonitrile extract of the plant sample; in the meantime, hydrophobic interferents from the extract were removed. Subsequently, magnetic sorbents served as a “microreactor”, where the cap- tured BRs were rapidly and efficiently derivatized with 4-dimethylphenyl boronic acid (DMPBA). The BR deriva- tives could be desorbed from the sorbents with water as the desorption solvent for further UPLC-ESI-MS/MS analysis. The proposed MSPE-ISD procedure could be accomplished within 10 min, and endogenous BRs could be detected in 100 mg fresh weight plant tissues.
11 Read more
Further, ∆ ∅ ° values of L-valine in both the surfactant solutions are negative. This indicates that hydrophobic- hydrophilic and hydrophobic-hydrophobic interactions dominate over hydrophilic- hydrophilic interactions in aqueous CTAB/TTAB-L-valine system The increase in ∆ ∅ ° with rise in temperature in both the aqueous surfactant solutions may be due to release of some solvent molecules from the loose hydration spheres of the solute in solution . It is worth mentioning that the values of ∆ ∅ ° from water to aqueous surfactant solutions at all the studied temperatures follow the sequence: CTAB > TTAB
DOI: 10.4236/sgre.2017.89019 297 Smart Grid and Renewable Energy With the increase of the photogeneration due to the intensification of the il- luminated light, another phenomenon which appears is the carriers concentra- tion gradient electric field. His orientation is illustrated in Figure 1 and its ex- pression is given by Equation (1). The expression of the electric field is inversely proportional to the carriers mobilities. Since the carriers mobility decrease with the increase of the temperature, consequently the electric field will increase with the increase of the temperature in the base of the solar cell. According to its orientation, it opposes to the movement of electrons toward the junction and to the move of holes to the rear side, and then has as effect to brake them. These braking releases also energy in the base of the solar cell and that contributes to heat the base of the solar cell. These three phenomena (energy released by ther- malization, carriers collisions and carriers braking) lead to an increase of the heat in the base of the solar cell.
15 Read more
Fro m NPH head, it was analyzed that as the voltage is increase the men iscus also expands on the surface. Thus another head was fabricated to re move the above mention instabilities. In this case a prominent head was introduced, in such a way that its acts like a converging nozzle head. The model and the fabricated structure of the pro minences hydrophilic (PH) nozzle a re shown in the fig. 7. The idea is to minimize the contact interaction area between the meniscus and the nozzle orifice. Firstly, the ink reservoir was developed and before using EDM the angle of the nozzle is developed using the pushing mechanism. When the electrostatic force is applied on the surface of the nozzle head, the voltage shapes in cone jet mode but the results are still not synchronized and the e xpanding behavior and hydrophilic behavior of the head makes it highly unstable.
Type-2 diabetes mellitus is a chronic progressive disorder characterized by defective insulin secretion and increased insulin resistance. It is widely accepted that it required intense and tight glycemic control to prevent several cardiovascular complications. Metformin hydrochloride is an orally administered biguanide, widely used in the management of type-2 diabetes, a common disease that combines defects of both insulin secretion and insulin action.  It is a hydrophilic drug which slowly and incompletely absorbed from the gastrointestinal tract; the absolute bioavailability is reported to be of 50 - 60% has relatively short biological half life of 1.5 - 4.5 h. [7, 8] However, frequent dosing schedule and risk of gastrointestinal symptoms make its dose optimization complicated. Thus, it is reasonable to assume the requirement of extended release metformin formulation to prolong its duration of action and to improve patient compliance.
recognizing not only the needs of the child affected with Duchenne or Becker muscular dystrophy, but also his mother who is a potential carrier. A unique opportunity exists for healthcare providers to share appropriate resources and information for mothers who are carriers. This may include educational pamphlets or reputable internet sources. One such online resource is PPMD, (www.parentprojectmd.org) and their DuchenneConnect Registry (www.duchenneconnect.org). The PPMD website provides information on care, research, and advocacy including detailed information for DBMD carriers. DBMD carriers are also encouraged to join the DuchenneConnect Registry.
62 Read more
Microsphere carriers were not suitable for loading endostar. Most drug-loaded microspheres are too large in diameter to be administered intravenously, because large- sized particulate carriers embolize easily in the blood ves- sels, triggering an opsonization effect in the immune system and they also have difficulty crossing endothelial barriers in various hosts. 30 Moreover, the effect of some medicines
In spite of the limitations of the current review and meta-analyses, the results from two previously pub- lished reviews [20, 23] in terms of UTI risk reduction associated to the use of hydrophilic coated catheters were verified. It should be noted that the meta- analyses of this study were limited to randomised clinical trials only to ensure high level of evidence but this is a limitation per se since few high quality trials exist and the available ones are compromised by quality issues . On the other hand, the results from this study also verify the results by several ob- servational studies that focused on the frequencies of UTIs [38, 39], urethral trauma , urethral compli- cations , microscopic haematuria, and pain .
11 Read more
carriage. 12, 26, 27 Hospitalization and household contact (most mothers and their children carry the same strain) have also been associated positively with nasal carriage rates. 22, 28 Patients undergoing haemodialysis, with end stage liver disease, with HIV, with skin disease, or with obesity have also been associated with having higher carriage rates. 3 Most (80%) individuals who develop a skin infection are S. aureus nasal carriers. 3 Using bacteriophage typing as a technique to discriminate different strains of S. aureus, 29 the majority of the cases where nasal colonization and skin infection occurred together, the infecting S. aureus was the same type as the colonizing. 3 Moreover, S. aureus nasal carriage increases the risk of nosocomial auto-infection after surgery, in patients undergoing dialysis, or in an immunosuppressed state by a factor of three. 30 Conversely, non-carriers have fourfold increased mortality rate from S. aureus bacteraemia compared to carriers. 30 This can be explained by the high titers of neutralizing antibodies that are found in carriers and are specific to the superantigens produced by their autologous colonizing strain. 31
128 Read more