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1.
Eur J Pharm Biopharm ; 69(3): 986-92, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18396020

RESUMEN

The aim of this study was to evaluate the effect of lubricants on the characteristics of orally disintegrating (OD) tablets manufactured using the phase transition of sugar alcohol. OD tablets were produced by directly compressing a mixture containing lactose-xylitol granules, disintegrant, glidant and lubricant, and subsequent heating. The effect of the type of lubricant on the tablet characteristics was evaluated using magnesium stearate (Mg-St), sodium stearyl fumarate (SSF), and talc as lubricants. The hardness of the tablets increased to ca. 6kp as a result of heating, regardless of the kind of lubricant. The oral disintegration time of the tablets containing Mg-St or SSF increased with an increase in the hardness. In contrast, the oral disintegration time of the tablets containing talc was not changed despite of an increase in hardness. The water absorption rate of the tablets containing talc was much faster than that of the tablets containing other lubricants. The surface free energy measurement showed that the polarity of the tablet components containing talc was remarkably increased by heating. The water absorption rate of the tablets containing talc was also increased by heating. These results indicate that a more hydrophilic surface might be attained by heating the talc. Consequently, talc was demonstrated to be the most desirable lubricant for the preparation of OD tablets based on the principle of the phase transition of sugar alcohol.


Asunto(s)
Lubricantes/química , Alcoholes del Azúcar/química , Absorción , Administración Oral , Fenómenos Químicos , Química Física , Excipientes , Fumaratos , Dureza , Lactosa , Porosidad , Solubilidad , Ácidos Esteáricos , Propiedades de Superficie , Comprimidos , Talco , Agua/química , Xilitol/química
2.
Int J Pharm ; 355(1-2): 87-92, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18182258

RESUMEN

In order to evaluate the effect of preparation method on the properties of orally disintegrating (OD) tablets, OD tablets were prepared by compressing a mixture of high melting point sugar alcohol (HMP-SA) and low melting point sugar alcohol (LMP-SA) and subsequent heating. In the direct compression method (DCM) where the LMP-SA was added as a powder, both hardness and disintegration time were increased by decreasing the particle size of the LMP-SA. In the wet granule compression method (WGCM), where the LMP-SA was added as an aqueous binder solution, the tablets became harder with less heating compared to tablets prepared by DCM. Using 1% xylitol as the LMP-SA provided tablets with sufficient hardness when prepared by WGCM, as opposed to DCM where 5% xylitol was necessary to prepare tablets with similar hardness. These results suggest that uniformly distributed LMP-SA on the surface of HMP-SA particles in WGCM might diffuse more easily during the heating process compared to mechanically mixed LMP-SA in DCM, resulting in an increase in tablet hardness even with a short heating time and low content of LMP-SA. In addition, disintegration and hardness stability of the tablets were affected by the LMP-SA content when prepared by WGCM, suggesting that the LMP-SA content should be regulated to assure the stability of OD tablet characteristics.


Asunto(s)
Comprimidos/química , Fenómenos Químicos , Química Física , Cristalización , Composición de Medicamentos , Eritritol/administración & dosificación , Eritritol/química , Dureza , Tamaño de la Partícula , Porosidad , Polvos , Solubilidad , Trehalosa/administración & dosificación , Trehalosa/química , Difracción de Rayos X , Xilitol/química
3.
J Control Release ; 105(1-2): 16-22, 2005 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-15955365

RESUMEN

The aim of the present study was to assess the properties of rapidly disintegrating (RD) tablets manufactured by the phase transition method. RD tablets were produced by compressing powder containing erythritol (melting point: 122 degrees C) and xylitol (melting point: 93 approximately 95 degrees C), and then heating at about 93 degrees C for 15 min. The hardness and oral disintegration time of the heated tablets increased with an increase of the xylitol content. These results suggested that the heating process and xylitol content might influence the properties of RD tablets. Then we evaluated the physicochemical properties of the RD tablets, including the median pore size, crystallinity, hardness, and oral disintegration time of tablets made with and without heating. After heating, the median pore size of the tablets was increased and tablet hardness was also increased. The increase of tablet hardness with heating and storage did not depend on the crystal state of the lower melting point sugar alcohol. It is concluded that a combination of low and high melting point sugar alcohols, as well as a phase transition in the manufacturing process, are important for making RD tablets without any special apparatus.


Asunto(s)
Alcoholes del Azúcar/química , Comprimidos , Preparaciones de Acción Retardada , Composición de Medicamentos , Excipientes , Dureza , Porosidad , Polvos , Solubilidad
4.
J Control Release ; 102(2): 373-81, 2005 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-15653158

RESUMEN

Surface-modified DL-lactide/glycolide copolymer (PLGA) nanospheres with chitosan (CS) were prepared by the emulsion solvent diffusion method for pulmonary delivery of peptide, i.e., elcatonin. The nanosphere suspension was successfully aerosolized with a nebulizer similar to the drug solution, whereas the microsphere suspensions could not be aerosolized. After pulmonary administration, CS-modified PLGA nanospheres were more slowly eliminated from the lungs than unmodified PLGA nanospheres. CS-modified PLGA nanospheres loaded with elcatonin reduced blood calcium levels to 80% of the initial calcium concentration and prolonged the pharmacological action to 24 h, which was a significantly longer duration of action than that by CS-unmodified nanospheres. These results were attributed to the retention of nanospheres adhered to the bronchial mucus and lung tissue and sustained drug release at the adherence site. In addition, CS and CS on the surface of the nanospheres enhanced the absorption of drug. The rank order of the absorption of the model drugs with CS solution was carboxyfluorescein>FITC-dextran-4 (FD-4; Mw. 4000)>FD-21 (Mw. 21,000)>FD70 (Mw. 70,000), which corresponded to the molecular weights ([Mw.] given in parentheses). The absorption-enhancing effect may have been caused by opening the intercellular tight junctions.


Asunto(s)
Calcitonina/análogos & derivados , Calcitonina/administración & dosificación , Quitosano/química , Ácido Láctico/química , Pulmón/metabolismo , Ácido Poliglicólico/química , Polímeros/química , Uniones Estrechas/química , Absorción , Adhesividad , Administración por Inhalación , Aerosoles , Animales , Calcitonina/química , Calcitonina/farmacocinética , Fenómenos Químicos , Química Física , Sistemas de Liberación de Medicamentos , Emulsiones , Cobayas , Masculino , Microesferas , Peso Molecular , Membrana Mucosa , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Propiedades de Superficie
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