scholarly journals Biopharmaceutical characterization of topical liposome formulations bearing 5-fluorouracil

2003 ◽  
Vol 48 ◽  
pp. 21-24
Author(s):  
Marija Glavas-Dodov ◽  
Emilija Fredro-Kumbaradzi ◽  
Sema Calis ◽  
Katerina Goracinova ◽  
Kristina Mladenovska ◽  
...  
Keyword(s):  
Drug Release ◽  
Aqueous Phase ◽  
Topical Administration ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Modified Release ◽  
Total Drug ◽  
Drug Release Rate ◽  
Gel Formulations

Liposome dispersions and liposome gel formulations for topical administration were evaluated as modified release delivery systems for 5-fluorouracil. Drug substance has been entrapped in the internal aqueous compartment of liposomes during the preparation. The concentration of 5-fluorouracil in the hydration medium was varied and the effect on the liposome characteristics was considered. Liposome gel formulations were prepared by incorporation of liophylized liposomes into a structured vehicle of chitosan. The decrease of the amount of aqueous phase bearing total drug quantity (drug/aqueous phase ratio from 1:100, 1:60, 1:40) led to an increase of the percentage of liposome-entrapped drug, and decreased percentage of drug release, while particle size analysis showed no changes in vesicle size. Liposome gel formulations showed initially a higher drug release rate in comparision with liposome dispersions, which could be related to the release of “free” 5-fluorouracil, leaked from liposomes due to the process of liophylization. This was followed by slower release (after 1.5 hour) as a result of the influence of the viscosity of the gel matrix.

Acyclovir Loaded Solid Lipid Nanoparticle Based Cream: A Novel Drug Delivery System

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
EL- Assal I. A. ◽  
Retnowati .
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Antiviral Agent ◽  
Study Drug ◽  
Particle Size Analysis ◽  
Stability Study ◽  
Size Analysis ◽  
Solid Lipid ◽  
Dermal Delivery

Objective of the present investigation was enthused by the possibility to develop solid lipid nanoparticles (SLNs) of hydrophilic drug acyclovir. Also study vitro and vivo drug delivery. Methods: Drug loaded SLNs (ACV-SLNs) were prepared by high pressure homogenization of aqueous surfactant solutions containing the drug-loaded lipids in the melted or in the solid state with formula optimization study (Different lipid concentration, drug loaded, homogenization / stirring speed and compritol 888ATO: drug ratio). ACV - SLN incorporated in cream base. The pH was evaluated and rheological study. Drug release was evaluated and compared with simple cream- drug, ACV – SLN with compritol 888ATO and marketed cream. The potential of SLN as the carrier for dermal delivery was studied. Results: Particle size analysis of SLNs prove small, smooth, spherical shape particle ranged from 150 to 200 nm for unloaded and from 330 to 444 nm for ACV loaded particles. The EE% for optimal formula is 72% with suitable pH for skin application. Rheological behavior is shear thinning and thixotropic. Release study proved controlled drug release for SLNs especially in formula containing compritol88 ATO. Stability study emphasized an insignificant change in SLNs properties over 6 month. In-vivo study showed significantly higher accumulation of ACV in stratum corneum, dermal layer, and receptor compartment compared with blank skin. Conclusion: AVC-loaded SLNs might be beneficial in controlling drug release, stable and improving dermal delivery of antiviral agent(s).

Bentonite Clays Characterization in the Town of Sossego – Paraiba State

2015 ◽  
Vol 820 ◽  
pp. 65-70
Author(s):  
I.D.S. Pereira ◽  
V.N.F. Lisboa ◽  
I.A. Silva ◽  
J.M.R. Figueirêdo ◽  
G.A. Neves ◽  
...  
Keyword(s):  
Industrial Applications ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Drilling Fluids ◽  
X Ray Diffraction ◽  
Mineralogical Characterization ◽  
Bentonite Clays ◽  
The Town ◽  
Petroleum Drilling

Bentonite exhibt a range of industrial applications moving millions of dollars on the market per year. Among several applications if highlights it is use for petroleum drilling fluids. Thus, this work aims to characterize physical, mineralogical and technologically, the bentonitics clays of Sossego County, Paraíba, Brazil. Mineralogical characterization of clays was done through the following techniques: particle size analysis by laser diffraction, thermogravimetric and differential thermal analysis, chemical analysis and x-ray diffraction. The clays were turned in by treatment with sodium in Na2CO3 and then determined whether the apparent viscosity, plastic and volume of filtrate of clay-water dispersions. The results showed that the samples are of polycationic, showing levels of MgO, CaO and K2O, similar to those from Boa Vista County, Paraíba, Brazil, and consist of clay mineral kaolinite, quartz and esmec. The clays showed rheological properties that indicate potential for use in drilling fluids.

Powders for Additive Manufacturing: From Design to Certification

2021 ◽  
Vol 1016 ◽  
pp. 1473-1478
Author(s):  
Oriana Tassa ◽  
Laura Alleva ◽  
Roberto Sorci
Keyword(s):  
Particle Size Analysis ◽  
Alloy Design ◽  
Size Analysis ◽  
Metal Powders ◽  
Process Standardization ◽  
Production Chain ◽  
Post Process ◽  
Treatment Conditions ◽  
New Process

Rina Consulting Centro Sviluppo Materiali (CSM) has been involved in the study and development of powder metallurgy for different applications, thanks to its participation in many research industrial and funded projects. The entire metal powder production chain takes place within the company's own researcher and facilities. This allows to produce high quality powders starting from alloy design, VIGA atomization and chemical, rheological and particle size analysis. In recent years, the development has mainly concerned manufacturing processes. Currently only a limited number of metal alloys can be processed by AM. For that reason, the alloy design becomes a really important topic to enlarge AM capabilities to other materials and applications. Starting from commercial Thermodynamic and Kinetic codes and proprietary models on solidification and micro-segregation, the alloy chemical composition can be fine-tuned to optimize the microstructure, considering the target properties of the material and the relevant AM processing windows, taking into account also the post process treatment conditions. Moreover, the knowledge of the production plants allows CSM to have a wide vision on the realization and the characterization of the metal powders focusing to achieve the best powder quality suitable for AM applications. Finally, AM is a relatively “new” process, standardization is still an ongoing activity involving several communities and organizations like ASTM, AWS and ISO; in this contest CSM has already designed the guidelines for qualification and certification processes and has created a dedicated laboratory to qualify powders of AM players.

scholarly journals PREPARATION AND CHARACTERIZATION OF ANTI-ACNE ETHOSOMES USING COLD AND THIN-LAYER HYDRATION METHODS

2018 ◽  
Vol 10 (1) ◽  
pp. 338
Author(s):  
Rachmawati Ramadhana Mustofa ◽  
Iskandarsyah .
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Thin Layer ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Multilamellar Vesicles ◽  
Zeta Potentials ◽  
Small Unilamellar Vesicles

Objective: This study aimed to prepare and characterize anti-acne ethosomes using the cold- and thin-layer hydration methods.Methods: A sonication step was included during ethosome preparation to improve the quality of the cold method. Azelaic acid, Phospholipon 90G,ethanol, propylene glycol, and phosphate buffer (pH 7.4) were used in the procedures. Prepared ethosomal suspensions were characterized usingtransmission electron microscopy, particle-size analysis, and spectrophotometry.Results: Ethosomes prepared using the thin-layer hydration method (F1) had small unilamellar vesicles, while those prepared using the cold methodwith 15-min sonication (F4) showed spherical, elliptical, unilamellar, and multilamellar vesicles. F1 ethosomes had a Dmean volume of 648.57±231.26,whereas those prepared using the cold method with 5- (F2), 10- (F3), and 15-min (F4) sonication had Dmean volumes of 2734.04±231.49 nm,948.90±394.52 nm, and 931.69±471.84 nm, respectively. Polydispersity indices of F2, F3, and F4 ethosomes were 0.74±0.21, 0.86±0.05, and 0.91±0.03,respectively, with a poor particle-size distribution, compared to that of F1 (0.39±0.01). Zeta potentials of F1–F4 ethosomes were −38.27±1.72 mV,−23.53±1.04 mV, −31.4±1.04 mV, and −34.3±1.61 mV, respectively. Entrapment efficiencies of F1–F4 ethosomes were 90.71±0.11%, 53.84±3.16%,72.56±0.28%, and 75.11±1.42%, respectively.Conclusion: Anti-acne ethosomes produced using the thin-layer hydration method had superior properties than those produced using the coldmethod with 15-min sonication.

Synthesis and Characterization of Nanocrystalline Hydroxyapatite Powder

2015 ◽  
Vol 1087 ◽  
pp. 142-146 ◽  
Author(s):  
Rosli Asmawi ◽  
Mohd Halim Irwan Ibrahim ◽  
Azriszul Mohd Amin ◽  
Najwa Mustapha ◽  
Iis Sopyan
Keyword(s):  
Particle Size ◽  
Calcium Phosphate ◽  
High Surface ◽  
High Surface Area ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Heating Process ◽  
X Ray Diffraction ◽  
Nanocrystalline Hydroxyapatite

Nanocrystalline hydroxyapatite (HA) powder was synthesized by a simple heating process involving simple chemical reaction. The characterization of the produced powder showed that the powder is nanosize with particle in the range of 30-70 mm in diameter and almost evenly spherical in shape. The powder also has a high surface area of 43.16 m2/g. Field Emission Scanning Electron Microscopy (FESEM) observation showed the crystallite and particle size become bigger with an increment of calcination temperature, indicating increasing of crystallinity.. FESEM observation showed the particle size become bigger with an increment of calcinations temperature. It is in agreement with the crystallite size analysis, obtained by Scherer’s formula and particle size analysis, measured by nanoSizer. X-ray Diffraction (XRD) and Fourier Transform Infra Red Spectroscopy (FTIR) analyses exhibited the same result, where HA phase was clearly observed at at various temperatures up to 600 ̊C. However, at temperature more than 600 ̊C, Tri calcium phosphate (TCP) phase appeared suppressing the HA phase, producing biphasic calcium phosphate.

Characterization and Granulometric Correction Soil for the Production of Soil-Cement Blocks for Two Method, Particle Size and X-Ray Florescence to be Inserted in Phase Change Materials (PCMS)

2014 ◽  
Vol 798-799 ◽  
pp. 355-359 ◽  
Author(s):  
Valter Bezerra Dantas ◽  
U.U. Gomes ◽  
A.B. Vital ◽  
G.S. Marinho ◽  
Ariadne de Souza Silva
Keyword(s):  
Particle Size ◽  
Phase Change Materials ◽  
Clay Content ◽  
Particle Size Analysis ◽  
Liquid Limit ◽  
Size Analysis ◽  
X Ray ◽  
Soil Cement

This paper presents the results of tests for characterization of soil samples collected in Mossoró-RN, UFERSA-RN Campus (5 ° 12'34 .68 "South latitude, 37 ° 19 '5.74 "west longitude), for the purpose of producing soil-cement for the manufacture of pressed blocks. Objective of improving the quality of soil-cement, and provide conditions for the use of the soil making it ideal for the production of soil-cement block. Tests of compaction, particle size analysis, plastic limit, liquid limit and correct particle size, X-ray fluorescence and morphology by scanning electron microscopy (SEM). It was concluded that the soil needs correction particle size, due to the high clay content. The method combined grading, sieving, sedimentation and blooming X-ray as the fastest and most accurate in correcting soil particle size.

Analysis of the Incorporation of Scheelite Residue in Kaolinitic Clay of Boa Saúde-RN

2012 ◽  
Vol 727-728 ◽  
pp. 844-849 ◽  
Author(s):  
Tércio G. Machado ◽  
Uilame Umbelino Gomes ◽  
Flanelson M. Monteiro ◽  
Samara M. Valcacer ◽  
Gilson G. da Silva
Keyword(s):  
Raw Materials ◽  
Particle Size Analysis ◽  
Northeastern Brazil ◽  
Size Analysis ◽  
Bending Tests ◽  
Materials Used ◽  
Kaolinitic Clay ◽  
The City ◽  
Mineral Waste

The scheelite occurs mainly in northeastern Brazil, with highest abundance in the states of Rio Grande do Norte and Paraíba - Scheelite Seridó Province. Mining is considered an activity that provides a high environmental degradation due to the large amount of minerals and waste involved. Most mining companies have no technologies or processes that allow the recycling of mineral waste generated. The aim of this study is to evaluate the influence of different percentages of reject on the mechanical properties of scheelite and aesthetic (staining of the final product after firing) of the clay of the city of Boa Saúde - RN. The raw materials used were characterized by XRD, XRF and particle size analysis. Assay was performed by water absorption, linear retraction and bending tests on three points for the characterization of the final product. The raw materials used were from the city of Currais Novos-RN.

scholarly journals Formulation and Characterization of Eplerenone Nanoemulsion Liquisolids, An Oral Delivery System with Higher Release Rate and Improved Bioavailability

Pharmaceutics ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 40 ◽  
Author(s):  
Ahmed Khames
Keyword(s):  
Drug Release ◽  
Delivery System ◽  
Release Rate ◽  
Oral Delivery ◽  
Oral Route ◽  
Drug Release Rate ◽  
Enhanced Absorption ◽  
Oral Delivery System ◽  
Characterization Studies

Because Eplerenone (EPL) is a Biopharmaceutical Classification System (BCS) class-II drug and is prone to extensive liver degradation, it suffers from poor bioavailability after oral administration. This work aimed to prepare liquisolids loaded with EPL-nanoemulsions (EPL-NEs) that have a higher drug release rate and improved bioavailability by the oral route. Based on solubility studies, mixtures of Triacetin (oil) and Kolliphor EL/PEG 400 surfactant/co-surfactant (Smix) in different ratios were used to prepare EPL-NE systems, which were characterized and optimized for droplet size, zeta potential, polydispersity index (PDI), and drug content. Systems were then loaded onto liquisolid formulations and fully evaluated. A liquisolid formulation with better drug release and tableting properties was selected and compared to EPL-NEs and conventional EPL oral tablets in solid-state characterization studies and bioavailability studies in rabbits. Only five NEs prepared at 1:3, 1:2, and 3:1 Smix met the specified optimization criteria. The drug release rate from liquisolids was significantly increased (90% within 45 minutes). EPL-NE also showed significantly improved drug release but with a sustained pattern for four hours. Liquisolid bioavailability reached 2.1 and 1.2 relative to conventional tablets and EPL-NE. This suggests that the EPL-NE liquisolid is a promising oral delivery system with a higher drug release rate, enhanced absorption, decreased liver degradation, and improved bioavailability.

Sign in / Sign up

Export Citation Format

Share Document