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1.
Abstract

The pellets of ascorbic acid were prepared from wet granulation using modifided spherical agglomeration technique, named as wet pelletization, in liquid media. The wet granules made by conventional method were placed into the baffled cylinderical vessel which was previously filled with water saturated ethylether. The wet granules were composed of ascorbic acid, microcrystalline cellulose and 3% of aqueous PVP K-30 solution as binding agent. To prepare highly spherical pellets with narrow size distribution, the system, at first, was agitated strongly about 1,500 rpm for 10 min with screw type agitator. Then the medium was changed to an anhydrous ethylether and agitated slowly about 900 rpm until pellets are shaped and densified. The shape and size distribution of pellets depend largely on the amounts of binding solution and the proportion of microcrystalline cellulose at fixed agitation speed. This wet pelletization technique was simple, reproducible and might have application for the spheronization of other hydrophilic drugs.  相似文献   

2.
The pellets of ascorbic acid were prepared from wet granulation using modifided spherical agglomeration technique, named as wet pelletization, in liquid media. The wet granules made by conventional method were placed into the baffled cylinderical vessel which was previously filled with water saturated ethylether. The wet granules were composed of ascorbic acid, microcrystalline cellulose and 3% of aqueous PVP K-30 solution as binding agent. To prepare highly spherical pellets with narrow size distribution, the system, at first, was agitated strongly about 1,500 rpm for 10 min with screw type agitator. Then the medium was changed to an anhydrous ethylether and agitated slowly about 900 rpm until pellets are shaped and densified. The shape and size distribution of pellets depend largely on the amounts of binding solution and the proportion of microcrystalline cellulose at fixed agitation speed. This wet pelletization technique was simple, reproducible and might have application for the spheronization of other hydrophilic drugs.  相似文献   

3.
Calcium phosphate substitutes drug delivery systems are well known substances used in minor bone void-filling to release their therapeutic agent in situ. Few studies associating anaesthetics and analgesics have been performed to date. The aim of this work was to study the association of the analgesic, morphine, and the local anaesthetic, lidocaine, with a calcium deficient apatite matrix. Three types of biomaterials i.e. powders, granules and blocks, were prepared by isostatic compression, wet granulation and a combination of the two, evaluated and compared. The chemical structure of the associated therapeutic agent was studied and the characteristics of the drug delivery systems were appraised in terms of drug release. The integrity of the lidocaine hydrochloride structure, as determined by RMN 1H, was confirmed regardless of the formulation technique used (isostatic compression or wet granulation). However, analyses of morphine hydrochloride by RMN 1H revealed slight structural modifications. The association and formulation techniques that were used made it possible to obtain an in vitro release time varying from 1 to 4 days for lidocaine hydrochloride and from 1 to 3 days for morphine hydrochloride.  相似文献   

4.
The feasibility of dextrose monohydrate as a non-animal sourced diluent in high shear wet granulation (HSWG) tablet formulations was determined. Impacts of granulation solution amount and addition time, wet massing time, impeller speed, powder and solution binder, and dry milling speed and screen opening size on granule size, friability and density, and tablet solid fraction (SF) and tensile strength (TS) were evaluated. The stability of theophylline tablets TS, disintegration time (DT) and in vitro dissolution were also studied. Following post-granulation drying at 60?°C, dextrose monohydrate lost 9% water and converted into the anhydrate form. Higher granulation solution amounts and faster addition, faster impeller speeds, and solution binder produced larger, denser and stronger (less friable) granules. All granules were compressed into tablets with acceptable TS. Contrary to what is normally observed, denser and larger granules (at ≥21% water level) produced tablets with a higher TS. The TS of the weakest tablets increased the most after storage at both 25?°C/60% RH and 40?°C/75% RH. Tablet DT was higher for stronger granules and after storage. Tablet dissolution profiles for 21% or less water were comparable and did not change on stability. However, the dissolution profile for tablets prepared with 24% water was slower initially and continued to decrease on stability. The results indicate a granulation water amount of not more than 21% is required to achieve acceptable tablet properties. This study clearly demonstrated the utility of dextrose monohydrate as a non-animal sourced diluent in a HSWG tablet formulation.  相似文献   

5.
Abstract

Hardness, disintegration and dissolution of compressed tablets were assessed by compressing tablets from granulations prepared by dry and wet granulation process of two sections and by composite wet granulation process. Modified USP XVIII apparatus for disintegration, rotating basket apparatus USP XVIII and constant circulation apparatus were employed for measuring dissolution. The constant circulation apparatus was used in the studies as only it proved to be sensitive to reflect the differences in the dissolution rates and was a close analog of physiological situation. Four types of tablets containing acetylsalicylic acid, codeine phosphate and propoxyphene hydrochloride were prepared. Tablets prepared by partial dry and wet granulation process did not show significant differences in the rates of dissolution as compared to those prepared by complete wet granulation process.  相似文献   

6.
Hardness, disintegration and dissolution of compressed tablets were assessed by compressing tablets from granulations prepared by dry and wet granulation process of two sections and by composite wet granulation process. Modified USP XVIII apparatus for disintegration, rotating basket apparatus USP XVIII and constant circulation apparatus were employed for measuring dissolution. The constant circulation apparatus was used in the studies as only it proved to be sensitive to reflect the differences in the dissolution rates and was a close analog of physiological situation. Four types of tablets containing acetylsalicylic acid, codeine phosphate and propoxyphene hydrochloride were prepared. Tablets prepared by partial dry and wet granulation process did not show significant differences in the rates of dissolution as compared to those prepared by complete wet granulation process.  相似文献   

7.
We developed a method for the optimization of dissolution properties of solid oral dosage forms manufacturing using high shear wet granulation (HSWG) by using near-infrared spectroscopy (NIRS) with chemometrics in small-scale experiments. The changes in rheology and NIR spectra of the granules were monitored to verify the granulation mechanism and determine the suitable water amount for model formulation during the HSWG. Tablets were manufactured by altering the added water amount to investigate the impact of the granulation mechanism on drug product qualities. Model formulation granules were prepared with 10–20% w/w water in a funicular state, corresponding to the plateau region in score plots obtained by principal component analysis (PCA). The dissolution rate of model formulation tablets manufactured with more than 20% w/w of water was significantly delayed while tablets manufactured with 15% w/w water showed 100% dissolution at 15?min. NIRS and PCA are applicable to the optimization of dissolution properties via the process understanding of HSWG at the early formulation development stage and could facilitate drug development.  相似文献   

8.
Drug-loaded porous spherical hydroxyapatite granules for bone regeneration   总被引:1,自引:0,他引:1  
Porous spherical hydroxyapatite (HAp) granules, which are not only can be used for bone void filler, but also drug delivery systems, were prepared using a liquid nitrogen method. Various pore and channel structures of spherical granules were obtained by adjusting the ratio of water to HAp powder and the amount of sodium chloride (NaCl). By using the water to powder ratio at 2.0 ml/g and the amount of NaCl at 15 wt% by powder, the spherical granules have optimal pore volume, micro-channel structure and strength to handle as well as the ability to work as a drug delivery system. When the NaCl content was 15 wt%, the micro-channel structure was changed, but the pore volume was maintained. For the drug release test, dexamathasone (Dex) was loaded as a model drug on the prepared HAp granules by the immersion method, and the drug release behavior was curved by a UV/vis spectrophotometer. As a result, different drug release behavior was observed according to micro-channel structural differences. Therefore, it was concluded that the NACl could be applied as the pore and micro-channel structure control agent. Porous spherical HAp granules, which were fabricated by a liquid nitrogen method, show potential as bone void filler with the ability of controlled drug release.  相似文献   

9.
《Materials Letters》2004,58(3-4):397-402
Porous calcium phosphates have important biomedical applications such as bone defect fillers, tissue engineering scaffolds and drug delivery systems. While a number of methods to produce the porous calcium phosphate ceramics have been reported, this study aimed to develop a new fabrication method. The new method involved the use of polyurethane foams to produce highly porous calcium phosphate cements (CPCs). By firing the porous CPCs at 1200 °C, the polyurethane foams were burnt off and the CPCs prepared at room temperature were converted into sintered porous hydroxyapatite (HA)-based calcium phosphate ceramics. The sintered porous calcium phosphate ceramics could then be coated with a layer of the CPC at room temperature, resulting in high porosity, high pore interconnectivity and controlled pore size.  相似文献   

10.
The aim of this work was to study the application of design of experiment (DoE) approach in defining design space for granulation and tableting processes using a novel gentle-wing high-shear granulator. According to quality-by-design (QbD) prospective, critical attributes of granules, and tablets should be ensured by manufacturing process design. A face-centered central composite design has been employed in order to investigate the effect of water amount (X1), impeller speed (X2), wet massing time (X3), and water addition rate (X4) as independent process variables on granules and tablets characteristics. Acetaminophen was used as a model drug and granulation experiments were carried out using dry addition of povidone k30. The dried granules have been analyzed for their size distribution, density, and flow pattern. Additionally, the produced tablets have been investigated for; weight uniformity, breaking force, friability and percent capping, disintegration time, and drug dissolution. Results of regression analysis showed that water amount, impeller speed and wet massing time have significant (p?相似文献   

11.
Abstract

The objective of this work was to study the dissolution process of sodium diclofenac granules coated with a polymeric suspension of Eudragit L-30D-55® by fluidized bed. Methacrylic acid-methylmetacrylate copolymer, also known as Eudragit, has been used as a pH sensitive coating material to protect drug substances prior to delivery to the human intestines. The sodium diclofenac granules were prepared by wet granulation technology using microcrystalline cellulose (MICROCEL), sodium diclofenac, and polivinilpirrolidone K-30. The granules coating operation was carried out in a fluidized bed with top spraying by a double-fluid nozzle. The dissolutions studies of the coated granules were performed in triplicate in a dissolution test station according to “in vitro testing requirements” Method A (paddle method, rotation of 100 RPM and temperature fixed at 37°C). The dissolution mediums were 0.1N HCl solution and a pH 6.8 phosphate buffer solution, following the pH change dissolution procedure specified in USP for enteric-coated articles: 2 h of exposure to 750 mL of 0.1N HCl followed by testing in 1000 mL of pH 6.8 phosphate buffer, the pH being adjusted with 250 mL of 0.2 M tribasic sodium phosphate solution. The released amount of sodium diclofenac was periodically determined by UV spectrophotometry at wavelength of 276 nm, using a spectrophotometer UV-VIS HP 8453. The coated product showed gastric resistance properties confirming the feasibility of the fluidized bed for applying enteric coating in granules and pharmaceutical powders.  相似文献   

12.
Spherical Ca-deficient hydroxyapatite (HA) granules are expected to be useful drug carriers in bony sites because of their bone regeneration and adsorption ability. In order to control drug loading and release ability of the granules, a controlled surface microstructure was constructed. Spherical Ca-deficient granules composed of micron-sized rod-shaped particles were prepared by hydrothermal treatment of α-tricalcium phosphate (α-TCP) granules, and then, submicron HA particles were precipitated on the obtained granules by immersion in a supersaturated calcium phosphate (CP) solution. When bovine serum albumin was used as a drug model, precipitation of submicron particles causes the loading capability to increase and the release rate to decrease. The spherical Ca-deficient HA granules with the controlled surface microstructure are expected to be useful drug carriers that can act as scaffolds for bone repair.  相似文献   

13.
The objective of this work was to study the dissolution process of sodium diclofenac granules coated with a polymeric suspension of Eudragit L-30D-55® by fluidized bed. Methacrylic acid-methylmetacrylate copolymer, also known as Eudragit, has been used as a pH sensitive coating material to protect drug substances prior to delivery to the human intestines. The sodium diclofenac granules were prepared by wet granulation technology using microcrystalline cellulose (MICROCEL), sodium diclofenac, and polivinilpirrolidone K-30. The granules coating operation was carried out in a fluidized bed with top spraying by a double-fluid nozzle. The dissolutions studies of the coated granules were performed in triplicate in a dissolution test station according to USP XXIII (1995) “in vitro testing requirements” Method A (paddle method, rotation of 100 RPM and temperature fixed at 37°C). The dissolution mediums were 0.1N HCl solution and a pH 6.8 phosphate buffer solution, following the pH change dissolution procedure specified in USP for enteric-coated articles: 2 h of exposure to 750 mL of 0.1N HCl followed by testing in 1000 mL of pH 6.8 phosphate buffer, the pH being adjusted with 250 mL of 0.2 M tribasic sodium phosphate solution. The released amount of sodium diclofenac was periodically determined by UV spectrophotometry at wavelength of 276 nm, using a spectrophotometer UV-VIS HP 8453. The coated product showed gastric resistance properties confirming the feasibility of the fluidized bed for applying enteric coating in granules and pharmaceutical powders.  相似文献   

14.
Context: Niacin (vitamin B3) is a micronized active pharmaceutical ingredient (API) with poor flow properties making the production of high-dose sustained-release tablets by direct compression a challenge.

Objective: We evaluated various wet granulation processes as a simple and efficient approach to obtain high-dose (500 and 1000?mg) niacin sustained-release lipid matrix tablets.

Materials and methods: A high melting-point lipid (Compritol® 888 ATO) was used as the sustained-release agent. Tablets were prepared by various wet granulation techniques, with different process parameters and binder concentrations to identify the optimal process conditions.

Results: A binder (PVP) was needed to increase particle bonding and tablet strength. Process parameters, such as spray rate and quantity of liquid, had only a slight impact on the properties of the granules and resultant tablets, in the presence of low binder concentrations. Increasing binder concentration improved granule wetting, resulting in significant granule growth and improved flow properties. Sustained-release over 12?h was observed for all the compacted granules, irrespective of the drug dose. The sustained-release kinetics for 1000?mg niacin matrix tablets with Compritol 888 produced with the identified optimal parameters were similar to those for the market reference product, Niaspan® FCT 1000?mg. The tablets were stable for up to six months when stored at 25 and 40?°C.

Conclusions: Wet granulation with Compritol 888 presents an effective approach to improve material flow and compressibility. High-dose lipid matrix tablets with sustained release profiles can be successfully produced.  相似文献   

15.
以掺锶β-磷酸三钙/硫酸钙为原料,利用搅拌喷雾干燥法制备出掺锶β-磷酸三钙/硫酸钙复合小球,再将硅胶与制备的复合小球复合,通过在模具中堆垛聚集的方法,制备出硅胶/掺锶β-磷酸三钙/硫酸钙复合生物支架。采用XRD,SEM,FT-IR等方法分析制得复合多孔支架的成分、形貌以及结构特征,并研究复合生物支架的降解性、孔隙率、力学性能和细胞毒性等。结果表明:该复合多孔生物支架具有一定的不规则孔洞结构,小球与小球之间的孔隙约为0.2~1mm,而每个小球上也有大量的微孔,孔径在50~200μm之间,且平均孔隙率达到62%,基本能满足骨组织工程支架对孔隙率的要求;该复合多孔支架无细胞毒性,其降解周期约为80天,抗压强度约为0.1MPa,因此该支架在非承重骨组织修复方面具有良好的应用前景。  相似文献   

16.
Secondary protonated calcium phosphates such as brushite (CaHPO4·2H2O) or monetite (CaHPO4) have a higher resorption potential in bone defects than sintered ceramics, e.g. tricalcium phosphate or hydroxyapatite. However, processing of these phosphates to monolithic blocks or granules is not possible by sintering due to thermal decomposition of protonated phosphates at higher temperatures. In this study a low temperature technique for the preparation of spherical brushite granules in a cement setting reaction is presented. These granules were synthesized by dispersing a calcium phosphate cement paste composed of β-tricalcium phosphate and monocalcium phosphate together with a surfactant to an oil/water emulsion. The reaction products were characterized regarding their size distribution, morphology, and phase composition. Clinically relevant granule sizes ranging from 200?μm to 1?mm were obtained, whereas generally smaller granules were received with higher oil viscosity, increasing temperature or higher powder to liquid ratios of the cement paste. The hardened granules were microporous with a specific surface area of 0.7?m2/g and consisted of plate-like brushite (>95?% according to XRD) crystals of 0.5–7?μm size. Furthermore it was shown that the granules may be also used for drug delivery applications. This was demonstrated by adsorption of vancomycin from an aqueous solution, where a load of 1.45–1.88?mg drug per g granules and an almost complete release within 2?h was obtained.  相似文献   

17.
Abstract

The applicability of a 10 litre high shear mixer for melt granulation of dicalcium phosphate and lactose is examined. Polyethylene glycol (PEG) 3000 and 6000 were used as melting binders in concentrations of 15-20% w/w. The effects of binder concentration, massing time, impeller speed, and particle size of the PEG 6000 on granule size, granule size distribution and intragranular porosity are investigated.

It is shown that pellets of a narrow size distribution can be produced by the use of a high impeller speed. Granule size and size distribution are markedly influenced by binder concentration and massing time. The particle size of the PEG has only a minor effect on the granule growth. Granule growth mechanisms by melt granulation are discussed on the basis of the liquid saturations and the amounts of binder liquid and are compared with previous results on wet granulation.  相似文献   

18.
Abstract

Different types of maltodextrin were evaluated as binding agents in wet granulation process. Maltodextrins were added during wet granulation process in the dry form or as a solution. The granulation was performed in a planetary and a high shear mixer. Lactose monohydrate and dicalcium phosphate dihydrate were used as bulk materials. This study showed no difference in binding capacity between the different types of maltodextrin. Maltodextrins did not show any advantage as binding agent in comparison to native starch.  相似文献   

19.
The purpose of this study was to investigate the effect of three process variables: distribution of hydroxypropyl methylcellulose (HPMC) within the tablet matrix, amount of water for granulation, and tablet hardness on drug release from the hydrophilic matrix tablets. Tablets were made both by direct compression as well as wet granulation method. Three formulations were made by wet granulation, all three having the exact same composition but differing in intragranular:intergranular HPMC distribution in the matrix. Further, each formulation was made using two different amounts of water for granulation. All tablets were then compressed at two hardness levels. Dissolution studies were performed on all tablets using USP dissolution apparatus I (basket). The dissolution parameters obtained were statistically analyzed using a multilevel factorial-design approach to study the influence of the various process variables on drug release from the tablets. Results indicated that a change in the manufacturing process could yield significantly dissimilar dissolution profiles for the same formulation, especially at low-hardness level. Overgranulation could lead to tablets showing hardness-dependent drug-release characteristics. Studies showed that intergranular addition of a partial amount of HPMC (i.e., HPMC addition outside of granules) provided a significant advantage in making the formulation more robust over intragranular addition (i.e., that in which the entire amount of HPMC was added to the granules). Dissolution profiles obtained for these tablets were relatively less dependent on tablet hardness irrespective of the amount of water added during granulation.  相似文献   

20.
The applicability of a 10 litre high shear mixer for melt granulation of dicalcium phosphate and lactose is examined. Polyethylene glycol (PEG) 3000 and 6000 were used as melting binders in concentrations of 15-20% w/w. The effects of binder concentration, massing time, impeller speed, and particle size of the PEG 6000 on granule size, granule size distribution and intragranular porosity are investigated.

It is shown that pellets of a narrow size distribution can be produced by the use of a high impeller speed. Granule size and size distribution are markedly influenced by binder concentration and massing time. The particle size of the PEG has only a minor effect on the granule growth. Granule growth mechanisms by melt granulation are discussed on the basis of the liquid saturations and the amounts of binder liquid and are compared with previous results on wet granulation.  相似文献   

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