scholarly journals СУЧАСНИЙ СТАН СТВОРЕННЯ, ВИРОБНИЦТВА ТА ДОСЛІДЖЕННЯ ТАБЛЕТОВАНИХ ЛІКАРСЬКИХ ПРЕПАРАТІВ Повідомлення 19. Сучасний стан розробки та дослідження мультипартикулярних пелетних систем.

Author(s):  
М. Б. Демчук ◽  
С. М. Гуреєва ◽  
Т. А. Грошовий

<p align="center"><strong>MODERN STATE OF CREATION, PRODUCTION AND RESEARCH OF DRUGS</strong></p><p align="center"><strong>M</strong><strong>.</strong><strong>B</strong><strong>. </strong><strong>Demchuk</strong><strong>, </strong><strong>S</strong><strong>.</strong><strong>M</strong><strong>. </strong><strong>Gureyeva</strong><strong><sup>1</sup></strong><strong>, </strong><strong>T</strong><strong>.</strong><strong>A</strong><strong>. </strong><strong>Hroshovyi</strong><strong></strong></p><p>TernopilStateMedicalUniversityby I.Ya. Horbachevsky</p><p><sup>1</sup>JSC “Farmak”</p><p><strong>Noti</strong><strong>ce</strong><strong> 19.</strong> The current state of development and research of multiple unit pellet systems.</p><p><strong>Summary: </strong>the literature on technological aspects of creations of pellets, features of compression pellet to obtain multiple unit pellet systems are summarized<strong>.</strong></p><p><strong>Keywords: </strong>pellets, methods of pellets, pellet pressing, multiple unit pellet systems.</p><p><strong>Introduction. </strong>Oral modified-release multiple-unit dosage forms have always been more effective therapeutic alternative to conventional or immediate release single-unit dosage forms. With regards to the final dosage form, the multiparticulates are usually formulated into single-unit dosage forms such as filling them into hard gelatin capsules or compressing them into tablets.</p><p>Pelletization is a technique that enables the formation of spherical beads or pellets with a mean diameter usually ranging from 0.5 to2.0 mm. These pellets can evantually be coated and very often used in controlled-release dosage forms. The use of pelletization and pellets leads to an improvement in the flowability, appearance and mixing properties, thus avoiding excessive dust and reducing segregation and, generally, eliminating undesirable properties and improving the physical or chemical properties of fine powders.</p><p>The pharmaceutical industry has developed a great interest in pelletization due to a variety of reasons:</p><p>– prevention of segregation of co-agglomerated components, resulting in an improvement of the uniformity of the content;</p><p>– prevention of dust formation;</p><p>– increasing bulk density and decreasing bulk volume;</p><p>– the defined shape and weight improves the appearance of the product;</p><p>– improvement of the handling properties, due to the free-flowing properties;</p><p>– improvement of the hardness and friability of pellets;</p><p>– controlled release application of pellets due to the ideal low surface area-to-volume ratio that provides an ideal shape for the application of film coatings.</p><p>Pellets are prepared by different techniques, such as extrusion and spheronisation, rotogranulation, solution, suspension or powder layering, spray-drying or spray-congealing.</p><p>Extrusion / spheronisation is a multistage process for obtaining pellets with uniform size from wet granulates (extrudates). The process is more labour-intensive and more expensive than the conventional wet-granulation technique, as its use should be limited only to the production of spherical pellets for controlled release of drugs.</p><p>The fluid-bed granulation consists in the spraying of a granulation solution onto the suspended particles, which then are dried rapidly in the hot air stream.</p><p>Rotogranulation is one of the most recent methods for the production of spheroids. The single-unit spheronizing system can be described using terms like centrifugal granulator, rotary fluidized-bed granulator, rotary fluid bed, rotary processor or rotor granulator.</p><p>Layering a suspension or a solution of a drug on a seed material (usually, a coarse crystal or nonpareil) can produce pellets that are uniform in size distribution and generally posess very good surphace morphology. These characteristics are especially desirable when pellets will be coated for the purpose of achieving a controlled release.</p><p>Dry powder layering is similar to the solution or suspension layering. Instead of these dispersions, the layering is performed using a drug powder.</p><p>Spray-drying represents another process with limited application in the development of pharmaceutical pelletized products, based on globulation. During spray-drying, a drug solution or suspension is sprayed, with or without excipients, into a hot-air stream, generating dry and highly spherical particles.</p><p>Spray-congealing (spray-chilling) is a technique similar to spray-drying. Spray-congealing is a process in which a drug is allowed to melt, disperse or dissolve in hot melts of gums, waxes, fatty acids or other melting solids. The dispersion is then sprayed into a stream of air and other gases with a temperature below the melting point of the formulation components.</p><p><strong>Conclusions.</strong> The basic requirements and approaches to development multiple unit pellet system, aspects and examples receipt of pellets and tablets based on them are described.</p>

2000 ◽  
Vol 1 (4) ◽  
pp. 62-70 ◽  
Author(s):  
Manuel Efentakis ◽  
Antonios Koutlis ◽  
Marilena Vlachou

Author(s):  
Zeynep Atak ◽  
Mehmet Koç ◽  
Figen Kaymak-Ertekin

There are various food-processing technologies with the aim of protecting foodstuffs from environmental factors and increasing their shelf life. One of these is encapsulation technology, which has recently been used with an increased interest. With the fluidized bed coating, which is one of the physical methods used for encapsulation, the solid core materials are fluidized via the air stream and a film layer is formed on the surface of the core material with the coating material. The applicability of the fluid bed coating technique, as well as particulate properties, is significantly influenced by process variables used in the system, environmental variables and thermodynamic factors. The release characteristics of capsules formed during the process can be changed by various mechanisms such as heating, dissolution, mechanical or chemical fracture etc. and controlled release can be achieved. The fluidized bed coating method not only has the advantage of controlled release but also provides a homogeneous powder product, reduction of fine particles, development of transport and storage facilities, protection of reactive components, and prevention unwanted taste and odour. In this study, researches on fluid bed coating mechanism, fluid bed coating systems and applications of fluid bed systems in the food industry have been reviewed.


Plants ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 124
Author(s):  
María J. Pascual-Villalobos ◽  
Manuel Cantó-Tejero ◽  
Pedro Guirao ◽  
María D. López

(E)-anethole is a phenylpropanoid that is the main compound found in the essential oils (EOs) of anise and fennel seeds, and either fumigant or direct contact activity of this compound has been demonstrated against aphids and stored product pests. In this work, solid microspheres were prepared by three methods—oil emulsion entrapment, spray-drying, and complexed with β-cyclodextrin. Fumigation activity of each microsphere preparation was tested against the green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), on pepper leaves. The best insecticidal activity was with (E)-anethole encapsulated in oil emulsion beads and introduced to aphids as a vapour over 24 h, with an LC50 of 0.415 μL/L compared to 0.336 μL/L of vapors from free (E)-anethole. Scanning electron microscopy of the beads revealed a compact surface with low porosity that produced a controlled release of the bioactive for more than 21 d, whilst most of the volatile was evaporated within two days if applied unformulated. Spray drying gave spherical particles with the greatest encapsulated yield (73%) of 6.15 g of (E)-anethole incorporated per 100 g of powder. Further work will be done on improving the formulation methods and testing the solid microspheres in all aphid stages scaling up the experimental assay. It is foreseen that nanotechnology will play a role in future developments of low risk plant protection products.


2020 ◽  
Vol 14 (3) ◽  
pp. 210-224
Author(s):  
Gayatri Patel ◽  
Bindu K.N. Yadav

Background: The purpose of this study was to formulate, characterize and in-vitro cytotoxicity of 5-Fluorouracil loaded controlled release nanoparticles for the treatment of skin cancer. The patents on nanoparticles (US8414926B1), (US61654404A), (WO2007150075A3) etc. helped in the selection polymers and method for the preparation of nanoparticles. Methods: In the present study nanoparticles were prepared by simple ionic gelation method using various concentrations of chitosan and sodium tripolyphosphate (TPP). Several process and formulation parameters were screened and optimized using 25-2 fractional factorial design. The prepared nanoparticles were evaluated for particle size, shape, charge, entrapment efficiency, crosslinking mechanism and drug release study. Results: The optimized 5-Fluorouracil loaded nanoparticle were found with particle size of of 320±2.1 nm, entrapment efficiency of 85.12%± 1.1% and Zeta potential of 29mv±1mv. Scanning electron microscopy and dynamic light scattering technique revealed spherical particles with uniform size. The invitro release profile showed controlled release up to 24 hr. Further study was carried using A375 basal cell carcinoma cell-line to elucidate the mechanism of its cytotoxicity by MTT assay. Conclusion: These results demonstrate that the possibility of delivering 5-Fluorouracil to skin with enhanced encapsulation efficiency indicating effectiveness of the formulation for treatment of basal cell carcinoma type of skin cancer.


2009 ◽  
Vol 620-622 ◽  
pp. 429-432 ◽  
Author(s):  
Gui Min Zhang ◽  
Zheng Yi Fu ◽  
Yu Cheng Wang ◽  
Hao Wang ◽  
Wei Min Wang ◽  
...  

Two different kinds of mullite precursors with composition 3Al2O3•2SiO2 (3:2) were prepared by conventional drying ethanol solution and spray-drying aqueous solution of aluminum nitrate nanohydrate and tetraethoxysilane, respectively. The results of scanning electron microscope (SEM) indicate that one powder consists of irregular particles with size of 1-10μm, the other powder is made of inhomogeneously sized hollow spherical particles with mean size of 0.5-5μm. The TG-DTA curves indicate the hollow spherical particles are unfavorable to eliminate the decomposed products. After the precursors were sintered by Spark Plasma Sintering at 1450°C for 10min, the microstructures of the former are made of fine equiaxed grains with sizes of around 0.5μm, the latter consist of elongated grains distributed in the matrix of fine grains with imhomogenous size of 0.5~10μm due to the liquid phase forming. The different microstructures lead to the former sintered body is transparent, while, the sample from spray-drying is opaque.


Sign in / Sign up

Export Citation Format

Share Document