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1.
J Biomater Appl ; 37(5): 859-871, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35999010

RESUMEN

In this study, an emulsion solvent evaporation method was used to produce Eudragit RL (ERL) nanoparticles (NPs) loaded with simvastatin (SIM) for the treatment of ulcerative colitis (UC). Accordingly, the effects of different formulation variables on the properties of NPs were evaluated using the Box-Behnken design. The optimized NPs were then coated by Eudragit FS30D (EFS30D). Drug release was studied in different physiological environments. Colitis was induced by 3% of acetic acid in rats, which received NPs of SIM (10 mg/kg/day), mesalazine (150 mg/kg/day), blank NPs and normal saline orally for 5 days. Macroscopic histopathological evaluation and biochemical analysis, including myeloperoxidase (MPO) activity and malondialdehyde (MDA) level in the colon tissues, were carried out in this study. The optimized SIM-ERL NPs showed the particle size of 182.48 ± 4.57 nm, the polydispersity index of 0.29 ± 0.12, the zeta potential of 26.45 ± 4.57 mV, drug loading % of 34.64 ± 0.48, the encapsulation efficiency % of 98.68 ± 0.69, and the release efficiency % of 35.78 ± 1.37. Coating the optimized NPs with EFS30D caused an increase in particle size and a decrease in the zeta potential of NPs. The optimized SIM-EFS30D/RL NPs improved the macroscopic and histopathological scores. Also, MPO activity and MDA level were reduced significantly by NPs, as compared to the control group. Therefore, this drug delivery system can be an alternative to the previous treatments of UC.


Asunto(s)
Colitis Ulcerosa , Nanopartículas , Ratas , Animales , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/patología , Simvastatina/uso terapéutico , Simvastatina/química , Nanopartículas/química , Sistemas de Liberación de Medicamentos/métodos , Tamaño de la Partícula , Concentración de Iones de Hidrógeno , Portadores de Fármacos/química
2.
Pharm Dev Technol ; 26(3): 335-348, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33430677

RESUMEN

A dual pH- and time-dependent polymeric coated capsule was developed to achieve the site specificity of simvastatin (SIM) release in the colon. To improve the SIM solubility, soluplus-based nanosuspension of the drug were prepared by applying the anti-solvent crystallization technique; this was then followed by lyophilization. Particle size, polydispersity index, and saturation solubility were evaluated. The optimized nanosuspension was combined with SLS and freeze-dried before filling into hard gelatin capsules. Drug release characteristics of the coated capsules were studied in HCl 0.1 N, the phosphate buffers 6.8 and 7.4, and the simulated colonic fluid (pH 6.8). The in-vitro cytotoxic effects of SIM nanoparticles against HT29 cells were then evaluated using the MTT assay. The prepared nanoparticles were spherical with a mean size of 261.66 nm, the zeta potential of -18.20 and the dissolution efficiency of 59.71%. X-ray diffraction and differential scanning calorimetry studies showed that the nanosizing technique transformed the crystalline drug into the more soluble amorphous form. The coated capsules had no release in the gastric media, providing the specific delivery of SIM in the colon. The cytotoxic effect of the SIM nanoparticles was significantly increased, as compared to the free SIM. The findings, therefore, showed that the coated capsules using the two polymers of ethyl cellulose and Eudragit S100 could be suitable for the colon target delivery of SIM.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Antineoplásicos/administración & dosificación , Preparaciones de Acción Retardada/química , Simvastatina/administración & dosificación , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Liberación de Fármacos , Células HT29 , Humanos , Concentración de Iones de Hidrógeno , Simvastatina/química , Simvastatina/farmacología
3.
IET Nanobiotechnol ; 14(2): 148-154, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32433032

RESUMEN

The objective of this study was to develop an in-situ gel containing lorazepam (LZM) loaded nanostructured lipid carriers (NLCs) for direct nose-to-brain delivery in order to increase drug therapeutic efficacy in the treatment of epilepsy. Accordingly, LZM loaded NLCs were formulated using emulsification solvent diffusion and evaporation method; then the effects of the formulation variables on different physicochemical characteristics of NLCs were investigated. Thermosensitive in-situ gels containing LZM-NLCs were prepared using a combination of chitosan and ß-glycerol phosphate (ß-GP). The anticonvulsant efficacy of LZM-NLCs-Gel was then examined using the pentylenetetrazole (PTZ) model. The optimised NLCs were spherical, showing the particle size of 71.70 ± 5.16 nm and the zeta potential of -20.06 ± 2.70 mV. The pH and gelation time for the chitosan solution with 15% (w/v) ß-GP were determined to be 7.12 ± 0.03 and 5.33 ± 0.58 min, respectively. The in-vivo findings showed that compared with the control group and the group that received LZM-Gel, the occurrence of PTZ-induced seizures in the rats was significantly reduced by LZM-NLCs-Gel after intranasal administration. These results, therefore, suggested that the LZM-NLCs-Gel system could have potential applications for brain targeting through nasal route and might increase LZM therapeutic efficacy in the treatment of epilepsy.


Asunto(s)
Quitosano/química , Geles/química , Lorazepam/farmacocinética , Nanoestructuras/química , Estado Epiléptico/tratamiento farmacológico , Administración Intranasal , Animales , Geles/administración & dosificación , Lípidos/química , Lorazepam/administración & dosificación , Lorazepam/uso terapéutico , Masculino , Nanoestructuras/administración & dosificación , Tamaño de la Partícula , Ratas , Ratas Wistar
4.
Int J Biol Macromol ; 151: 220-229, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32027902

RESUMEN

Hydrogel scaffolds have been frequently utilized due to their ability to absorb water and develop similar body cell conditions. Specific drug delivery to the tissues ensures less adverse side effects and more efficiency. In the present study, carboxymethyl chitosan (CMC)-methylcellulose (MC)-pluronic (P) and zinc chloride hydrogels containing meloxicam loaded into nanoparticles were developed and characterized. Nanoparticles were incorporated at 3.5, 4.5 and 5.5% (w/v). Hydrogels containing the same amounts of the meloxicam solution were also prepared. Gelation time, swelling and degradation of the hydrogels were investigated. Hydrogels were characterized by scanning electron microscopy (SEM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and rheological analysis. Meloxicam release, chondrocytes attachment and growth on the hydrogels were also studied. Gelation time, swelling and the degradation rate of the hydrogels were found to be decreased by nanoparticles and increased with the addition of the meloxicam solution. SEM images also showed three-dimensional networks. The ATR-FTIR bands were shifted to the lower wave numbers in the hydrogels containing nanoparticles and shifted to the upper ones in the hydrogels containing meloxicam solution. Storage (G') and loss (G″) modulus were increased by the nanoparticles and reduced by the meloxicam solution. 100% of meloxicam was released from the hydrogels containing the meloxicam solution within 20 days, but it was released slowly from the hydrogels containing nanoparticles in 37days. Chondrocytes metabolic activity was increased on the 6th and 10th days for all hydrogels. Hydrogel containing nanoparticles showed good biocompatibility, bioadhesion, cell growth and expansion. The hydrogel could be, therefore, suitable as a new composite biomaterial for the regeneration of articular cartilage and meloxicam delivery to control the pain and inflammation in osteoarthritis.


Asunto(s)
Quitosano/análogos & derivados , Portadores de Fármacos/química , Hidrogeles/química , Meloxicam/administración & dosificación , Metilcelulosa/química , Nanopartículas/química , Poloxámero/química , Fenómenos Químicos , Quitosano/química , Condrocitos/citología , Sistemas de Liberación de Medicamentos , Humanos , Cinética , Reología , Análisis Espectral
6.
Pharm Dev Technol ; 24(7): 891-901, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31062987

RESUMEN

This study was conducted to develop an in situ thermosensitive gel containing sertaconazole-loaded nanostructured lipid carriers (NLCs) for prolonged ocular drug delivery. To this end, sertaconazole-loaded NLCs (sertaconazole-NLCs) were prepared by emulsification solvent-diffusion method and the effects of different formulation variables were assessed using the fractional factorial design. Then, optimized sertaconazole-NLCs were incorporated into the pluronic F127 (PF127)/hydroxy propylmethylcellulose (HPMC) K4M hydrogel. The formulations were examined for pH, gelation temperature, rheological properties, in vitro permeation studies, and anti-fungal activity. The optimized sertaconazole-NLCs showed a mean particle size of 272.40 nm, encapsulation efficiency of 89.97%, zeta potential of 12.9 mV, and polydispersity index of 0.31. All the in situ formulations had acceptable pH, ranging from 5.89 to 6.28. The gelation temperature of the optimized formulation was 35.1 °C after dilution with simulated tear fluid (STF). Sertaconazole-NLCs showed a higher antifungal activity and permeation through the bovine cornea compared to the free drug and the in situ gel formulation. The cornea penetration of sertaconazole for the in situ gel of NLCs was also comparable to that for free drug. The obtained results indicated that the prepared nanocomposite system may have potential for treatment of fungal keratitis.


Asunto(s)
Antifúngicos/administración & dosificación , Portadores de Fármacos/química , Imidazoles/administración & dosificación , Lípidos/química , Nanopartículas/química , Tiofenos/administración & dosificación , Animales , Antifúngicos/farmacocinética , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Bovinos , Córnea/metabolismo , Liberación de Fármacos , Hidrogeles/química , Imidazoles/farmacocinética , Imidazoles/farmacología , Queratitis/tratamiento farmacológico , Nanopartículas/ultraestructura , Poloxámero/química , Temperatura , Tiofenos/farmacocinética , Tiofenos/farmacología
7.
J Pharm Bioallied Sci ; 10(4): 208-215, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30568378

RESUMEN

AIM: Glycyrrhiza glabra (G. glabra) or licorice with isoflavonoid, flavonoids, and triterpenoid glycosides (saponins) components are highly regarded in the cosmetic industry. This study has been planned as the first project for formulating a new herbal shampoo by utilizing the aqueous extracts of G. glabra. MATERIALS AND METHODS: The dried powdered root of G. glabra was extracted with boiled water through percolation method, and the pH was set by ammonia; then it was used with other constituents to formulate the herbal shampoo. The desirability of licorice shampoo was evaluated by physicochemical tests including visual inspection, detergency evaluation, pH assessment, percentage of solid contents, viscosity, foaming volume, and wetting time and compared with a commercial shampoo. Also, the product was checked for microbial control and consumers were asked about the quality of the licorice shampoo. RESULTS: The licorice shampoo has excellent cleansing ability, acceptable clarity, and viscosity. The volume of created foam and the wetting time were similar to the commercial shampoo. No microbial contamination was observed during the microbial control assessment tests. The licorice shampoo scored well on consumer's poll and was free from complication and also able to obviate hair and scalp problems. DISCUSSION AND CONCLUSION: The results indicated that the consumers were satisfied with using the formulated licorice shampoo. Licorice shampoo seems to be helpful in obviation of hair problems, but specific investigations are required to prove this claim. The shampoo was safe from microbial contamination and showed acceptable results in physicochemical evaluations. Licorice shampoo could be useful in the treatment of many hair diseases, so further research is needed for discovering the potential of licorice shampoo.

8.
Res Pharm Sci ; 12(2): 128-136, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28515765

RESUMEN

In the current study, floating dosage form containing acyclovir was developed to increase its oral bioavailability. Effervescent floating tablets containing 200 mg acyclovir were prepared by direct compression method with three different rate controlling polymers including Hydroxypropyl methylcellulose K4M, Carbapol 934, and Polyvinylpyrrolidone. Optimized formulation showed good floating properties and in vitro drug release characteristics with mean dissolution time and dissolution efficacy of about 4.76 h and 54.33%, respectively. X-ray radiography exhibited that the tablet would reside in the stomach for about 5 ± 0.7 h. After oral administration of floating tablet containing 200 mg acyclovir, the Cmax, Tmax , and AUC0-∞ of optimized gastroretentive formulation were found to be 551 ± 141 ng/mL, 2.75 ± 0.25 h and 3761 ± 909.6 ng/mL/h, respectively.

9.
Res Pharm Sci ; 10(5): 419-28, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26752990

RESUMEN

Celecoxib is used in the treatment of osteoarthritis, rheumatoid arthritis, acute pain, joint inflammation and sport injuries. Long term administration of the drug results in such complications as gastrointestinaland renal disturbances and cardio-vascular complications. The main objective of the present study was to investigate the feasibility of delivering celecoxib incorporated in gel formulations by iontophoresis. Sodium alginate, sodium carboxymethyl cellulose, hydroxypropyl methylcellulose (HPMC) and carbopol 934P were used to develop topical gel formulations of celecoxib. The gel formulations were evaluated for macroscopic and microscopic properties, pH determination, spreadability, rheological behaviour, and drug release characteristics both in vitro and ex vivo. Drug release was evaluated in the presence of iontophoresis field (0.1 to 0.5 mA/cm(2)) or without electrical current (passive diffusion) and celecoxib was measured spectrophotometrically at 252 nm. Most gel formulations showed acceptable physicochemical properties. Amongst formulations, gel formulation containing HPMC K4M which indicated greater performance in drug release behaviour was selected for further in vivo studies. The cumulative percent of drug released in vitro at the end of each experiment was 36%, 63%, and 89.7% for passive diffusion, direct electric current (DC) current density of 0.3 mA/cm(2), and 0.5 mA/cm(2), respectively. The findings of ex vivo drug transport across rat skin also showed a significantly higher release of celecoxib compared to passive flux for both AC and DC currents. A 0.5 mA/cm(2) of DC current increased drug flux to 73% compared to 41.5% of passive diffusion. It can be concluded from the results of this study that the application of iontophoresis enhances the flux of celecoxib, as compared to the passive diffusion.

10.
Adv Biomed Res ; 3: 111, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24804185

RESUMEN

BACKGROUND: Leishmaniasis is still one of the endemic parasitic infections in many countries comprising Iran. During the past decades, several medical and surgical approaches have been applied and studied to achieve the best option to treat the cutaneous leishmaniasis in Iran and the world. This study was carried out to evaluate the effect of topical Achilles millefolium in conjunction with intralesional glucantime on acute cutaneous leishmanial lesions. MATERIALS AND METHODS: sixty patients with confirmed acute cutaneous leishmaniasis were recruited in the study. Patients were randomly allocated into two groups to receive twice daily topical gel of Achilles millefolium 5% (containing 5% poly phenol) (group A) or placebo (group B) for four weeks along with weekly injection of intralesional Glucantime. RESULTS: There was no significant difference between the two groups according to age, gender, and duration of the disease. Also, there was no significant difference in complete and relative cure rates between the two groups (P = 0.35) using Visual Analog Scale (VAS). Application site reactions were occurred in 12 patients including redness in 8 cases in group-A and 2 cases in group-B, severe itching in one case in group-A and increasing wound secretion in another case in group-A (P = 0.014). CONCLUSIONS: Given the result of the present study, there is no significant difference in cure rates of lesions between yarrow and placebo topical gels as an adjuvant drugs with intralesional glucantime in treatment of acute cutaneous leishmanial lesions.

11.
J Microencapsul ; 31(6): 529-34, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24697183

RESUMEN

Repaglinide, an oral antidiabetic agent, has a rapid onset of action and short half-life of approximately 1 h. Designing a controlled release dosage form of the drug is required to maintain its therapeutic blood level and to eliminate its adverse effects, particularly the hypoglycaemia. Repaglinide sustained release matrix pellets consisting of Avicel, lactose and different polymers were prepared using extrusion-spheronisation method. The effect of different formulation components on in vitro drug release were evaluated using USP apparatus (paddle) for 12 h in phosphate buffer. The optimised formulation was orally administrated to normal and STZ induced diabetic rats. Most pellet formulations had acceptable physical properties with regard to size distribution, flowability and friability. Repaglinide pellets comprising Avicel 50%, lactose 47% and SLS 1% were released 94% of its drug content after 12 h. The optimised formulation was able to decrease blood glucose level in normal rats and those with diabetes throughout 8-12 h.


Asunto(s)
Carbamatos , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes , Piperidinas , Administración Oral , Animales , Glucemia/metabolismo , Carbamatos/química , Carbamatos/farmacocinética , Carbamatos/farmacología , Celulosa/química , Diabetes Mellitus Experimental/sangre , Evaluación Preclínica de Medicamentos , Implantes de Medicamentos/farmacocinética , Implantes de Medicamentos/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/farmacocinética , Hipoglucemiantes/farmacología , Lactosa/química , Masculino , Piperidinas/química , Piperidinas/farmacocinética , Piperidinas/farmacología , Ratas , Ratas Wistar
12.
Phys Chem Chem Phys ; 15(47): 20510-6, 2013 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-24177354

RESUMEN

In this study, the transfection ability and cytotoxicity of a series of phytanyl substituted gemini surfactants, rationally designed and synthesized in an attempt to create cationic surfactants that will improve transfection efficiencies of non-viral vectors was evaluated in OVCAR-3 cells at the charge ratios (N(+)/P(-)) of 2:1, 5:1, and 10:1. Particle sizes, zeta potentials, and small angle X-ray scattering (SAXS) profiles were also determined. For each gemini surfactant complex, the transfection efficiency and cytotoxicity are observed to go through a more or less well-evidenced maximum, occurring at different values of the charge ratio (N(+)/P(-)), depending on the surfactant structure. Considering both results of in vitro transfection efficiency and cytotoxicity, the optimal charge ratio to formulate the complexes containing phy-3-m was found to be 5:1. The particle size decreased, while zeta potential increased with increasing N(+)/P(-). Comparing particle size and zeta potential with transfection efficiency, no correlation between size/zeta potential and transfection ability was observed. Analysis of SAXS profiles indicates that the ability of phy-3-m delivery system to adopt multiple phases correlated well with their higher transfection efficiency in OVCAR-3 cells.


Asunto(s)
Diterpenos/química , Tensoactivos/química , Transfección , Cationes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Tamaño de la Partícula , Dispersión del Ángulo Pequeño , Tensoactivos/toxicidad , Difracción de Rayos X
13.
Brain Inj ; 27(12): 1454-60, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24088189

RESUMEN

OBJECTIVES: This pilot trial was conducted to establish whether Boswellia Serrata (BS), a traditional herbal medicine, could improve the outcome of patients who have diffuse axonal injury (DAI). METHODS: In total, 38 patients with pure DAI were enrolled in this 12-week, double-blind, randomized, cross-over study. The patients were randomly assigned to receive either placebo (group A, n = 20) or BS capsules (group B, n = 18) for 6 weeks and then switched to the other intervention for another 6 weeks. The disability rating scale (DRS) was used to assess the outcome at 2-, 6- and 12-weeks post-trauma. RESULTS: A non-significant trend for improvement of DRS total scores was observed after the use of BS. Regarding the DRS sub-scores, however, there was significant improvement in 'cognitive ability to self-care' during the second 6 weeks in group A on BS compared to an insignificant spontaneous recovery in group B during the same period on placebo. Moreover, both groups experienced a close-to-significant increase in the cognitive function-related items of the DRS during the periods they were on BS. The reported adverse events were all of mild quality and had similar frequency between the groups. CONCLUSION: These results suggest that BS resin does not significantly affect general outcome, but may enhance the cognitive outcome of patients with DAI.


Asunto(s)
Boswellia , Cognición/efectos de los fármacos , Lesión Axonal Difusa/tratamiento farmacológico , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Autocuidado/estadística & datos numéricos , Accidentes de Tránsito/estadística & datos numéricos , Adulto , Estudios Cruzados , Lesión Axonal Difusa/epidemiología , Lesión Axonal Difusa/fisiopatología , Evaluación de la Discapacidad , Método Doble Ciego , Femenino , Escala de Coma de Glasgow , Humanos , Puntaje de Gravedad del Traumatismo , Irán/epidemiología , Masculino , Fitoterapia/métodos , Proyectos Piloto , Recuperación de la Función , Resultado del Tratamiento
14.
J Drug Deliv ; 2012: 905191, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22577558

RESUMEN

Budesonide, a potent glucocorticoid, is used for the treatment of inflammatory bowel diseases. Current available oral formulations of budesonide have low efficacy against ulcerative colitis because of the premature drug release in the upper part of the gastrointestinal tract. In this paper a pH- and time-controlled colon-targeted pellet-based tablet of budesonide was established. Pellet cores were prepared by extrusion-spheronization method and further coated with xanthan gum (barrier layer), Eudragit NE30D and L30D55 combination (inner layer), and Eudragit FS30 (as enteric layer) sequentially to achieve the required release profile. The coated pellets then compressed into tablets using inert tabletting granules of Cellactose or Pearlitol. Release studies, performed in simulated gastric, intestinal, and colon pH were used in sequence to mimic the gastrointestinal transit. The influence of formulation variables like barrier layer thickness, inner layer composition, and enteric coat thickness on drug release were investigated and the coated pellets that contained 12% weight gain in xanthan gum layer, Eudragit L30D55 and Eudragit NE30D with a ratio of 3 : 7 in inner layer with 30% weight gain and 25% weight gain in Eudragit FS layer were found to protect the drug release in stomach and small intestine and 83.35 ± 2.4 of budesonide was released at 24 h. The drug release from the tablets prepared using 40% Cellactose 80 as tableting excipient was found to be closely similar to that of uncompressed pellets.

15.
J Colloid Interface Sci ; 377(1): 237-43, 2012 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-22515995

RESUMEN

An evaluation of the physical interactions between gemini surfactants, DNA, and 1,2-dialkyl-sn-glycero-3-phosphoethanolamine helper lipid is presented in this work. Complexation between gemini surfactants and DNA was first investigated using surface tensiometry where the surface tension profiles obtained were found to be consistent with those typically observed for mixed surfactant-polymer systems; that is, there is a synergistic lowering of the surface tension, followed by a first (CAC) and second (CMC) break point in the plot. The surfactant alkyl tail length was observed to exhibit a significant effect on the CAC, thus demonstrating the importance of hydrophobic interactions during complexation between gemini surfactants and DNA. The second study presented is an investigation of the mixing interactions between gemini surfactants and DOPE using Clint's, Rubingh's, and Motomura's theories for mixed micellar formation. The mixing interactions between the 16-3-16/16-7-16/16-12-16/16-7NH-16 gemini surfactants and DOPE were observed to be antagonistic, where the strength of antagonism was found to be dependent upon the gemini surfactant spacer group and the solution composition.


Asunto(s)
Fosfatidiletanolaminas/síntesis química , Tensoactivos/síntesis química , Animales , ADN/química , Estructura Molecular , Fosfatidiletanolaminas/química , Salmón , Tensoactivos/química
16.
Chem Pharm Bull (Tokyo) ; 60(2): 172-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22293475

RESUMEN

Acyclovir (ACV), a model drug for this study, is one of the most effective drugs against viruses of the herpes group. Absorption of orally administered ACV is variable and incomplete, with a bioavailability of ca. 15-30%. The drug is absorbed in the duodenum after oral administration and hence, preparation of a floating drug delivery system (FDDS) for ACV may increase oral absorption of the drug. ACV matrix tablets (200 mg) containing an effervescent base (sodium bicarbonate and citric acid) and a binary combination of hydroxypropyl methylcellulose (HPMC) K4M with carbopol or sodium carboxymethyl cellulose (Na CMC) or polyvinylpyrrolidone (PVP) and/or sodium alginate were prepared by the direct compression method. The tablets were evaluated for physicochemical properties and in vitro floating ability (floating lag-time and duration), bioadhesiveness and drug release. The drug release studies were carried out in 0.1 N HCl (pH 1.2) at 37±0.5°C. At appropriate time intervals, samples were withdrawn and assayed spectrophotometrically at λ(max)=259 nm. The floating test showed tablets containing 15% effervescent base had a floating lag time of 10-30 s and a duration of floating time of 24 h. The formulations containing HPMC-PVP, HPMC-Na CMC, HPMC-carbopol, and HPMC-sodium alginate released about 60-90% of their drug content during a 12-h period. Increasing carbopol caused slower drug release. We concluded that the proposed tablets with 15% effervescent base, 20-30% HPMC, 30% Na CMC (and/or 20% PVP or 20% sodium alginate) showed good floating and drug release properties in vitro, and should be considered as FDDS for ACV.


Asunto(s)
Aciclovir/administración & dosificación , Antivirales/administración & dosificación , Sistemas de Liberación de Medicamentos/normas , Aciclovir/farmacocinética , Antivirales/farmacocinética , Disponibilidad Biológica , Comprimidos/administración & dosificación , Comprimidos/química
17.
Acta Pharm ; 62(3): 341-56, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23470347

RESUMEN

Three layered pellets of budesonide were prepared for colon delivery by the extrusion-spheronization method. The coatings consisted of hydroxypropylmethyl cellulose (HPMC) (as barrier layer), Eudragit E (as rate controlling layer) and hydroxypropylmethyl cellulose acetate succinate (HPMC AS) (as enteric layer). The rate controlling layer was further modified using various pore formers. Dissolution studies were carried out at pH 1.2, 7.4 and 6.8. Pellet core composition and type and level of pore former affected the drug release from pellets. Pellets containing 20% (m/m) citric acid in the cores coated with HPMC at a coating level of 6% (m/m), Eudragit E containing Avicel RC 581 (30%) as pore former at a coating level of 30% (m/m) and HPMC AS at a coating level of 15% (m/m) had the best release profiles. These pellets showed promising results in alleviating the conditions of an experimental model of colitis induced by trinitrobenzenesulfonic acid in rats.


Asunto(s)
Antiinflamatorios/administración & dosificación , Budesonida/administración & dosificación , Sistemas de Liberación de Medicamentos , Excipientes/química , Animales , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Budesonida/química , Budesonida/uso terapéutico , Celulosa/química , Fenómenos Químicos , Ácido Cítrico/química , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/patología , Colon/efectos de los fármacos , Colon/inmunología , Colon/patología , Composición de Medicamentos , Concentración de Iones de Hidrógeno , Lactosa/química , Masculino , Metilcelulosa/análogos & derivados , Metilcelulosa/química , Tamaño de la Partícula , Ratas , Ratas Wistar , Solubilidad , Comprimidos Recubiertos
18.
Iran J Pharm Res ; 11(3): 733-45, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24250500

RESUMEN

The main objective of this study was to prepare colon-specific pellets of budesonide, using pectin as film coating. Pellet cores of budesonide were prepared by extrusion / spheronization technique. Pectin, in different ratios was combined with Eudragit RS30D, Eudragit NE30D or Surelease to produce film coating. The dissolution profiles of pectin coated pellets were investigated in pH of 1.2 (2 h), pH of 7.4 (4 h) and pH of 6.8 in the absence as well as presence of rat cecal contents (18 h). Finally the selected formulation was evaluated on trinitrobenzenesulfonic acid (TNBS) induced ulcerative colitis in rat model, in comparison with conventional UC treatments. The dissolution profiles of pectin coated pellets showed that the release of budesonide in presence of rat cecal content depended on adjuvant polymer, the ratio of pectin to polymer and film thickness. Coated pellets, prepared out of pectin and Surelease at a ratio of 1:3 at coating level of 35% (w/w), could increase budesonide release statistically in presence of rat cecal content, while they released no drug in pH of 1.2 and 7.4. Animal experiments revealed the therapeutic efficacy of pectin/Surelease-coated pellets of budesonide in alleviating the conditions of TNBS-induced colitis model as reflected by weight gain, as well as improvement of clinical, macroscopic and microscopic parameters of induced colitis. This confirmed the ability of the optimized formulation for targeted drug delivery of budesonide to colon.

19.
Dent Res J (Isfahan) ; 8(3): 113-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22013472

RESUMEN

BACKGROUND: Surface microhardness is a physical property which access the effect of chemical and physical agents on hard tissues of teeth, and a useful way to examine the resistance of fluoride treated enamel against caries. The purpose of this study was to evaluate microhardness of enamel following pH-cycling through demineralization and remineralization using suspensions of dentifrices with different fluoride contents. METHODS: In this in vitro study 56 enamel blocks of primary incisors were soaked in demineralizing solution and four dentifrices suspensions including: Crest 1100 ppm F (NaF), Crest 500 ppm F (NaF), Pooneh 500 ppm F (NaF,) and Pooneh without fluoride. The means and percentage changes of surface microhardness in pre-demineralization, after demineralization and remineralization stages in four groups were measured. The findings of four groups in three stages were compared by, ANOVA, Tukey and paired t-tests. (α=0.05) RESULTS: Average surface microhardness changes of Crest 1100 ppm F, was higher than Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride. The percentages of surface microhardness recovery for Crest 1100 ppm F, Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride were 45.4, 35.4, 28.6, and 23.7 respectively. Demineralization treatment decreased the surface microhardness of enamel (P<0.05) and the surface microhardness recovery in all groups were significant (P<0.0001). CONCLUSION: Surface microhardness of enamel after remineralization by Crest 1100 ppm F was higher than Crest 500 ppm F, Pooneh 500 ppm F, and Pooneh without fluoride.

20.
Drug Deliv ; 18(2): 122-30, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20954795

RESUMEN

Budesonide is an anti-inflammatory drug of choice for treatment of ulcerative colitis which affects the rectum and a part of or the entire colon. Delivery of budesonide specifically to the colon would increase the efficacy of the drug and reduce the side-effects. The aim of this study was to develop an oral matrix system formulation for budesonide to deliver the major part of the drug to the colon for treatment of ulcerative colitis that has not been reported before. Directly compressed matrix tablets were prepared using different molecular weights of dextran and three ratios of drug-to-polymer. The physical properties of the tablets including weight variation, hardness, content uniformity, and release profile in HCl 0.1 N, phosphate buffer pH 7.4 and 6.8 containing 4% rat caecal and colonic contents were studied. The efficacy of the desired formulation was also evaluated against acetic acid-induced colitis in rats. Physical properties of the tablets were in the ranges recommended by official references. More than 10% of the drug was released in HCl 0.1 N and pH 7.4, while a very drastic increase was observed after exposure to pH 6.8 containing rat caecal contents. The efficacy of the selected formulation against rat-induced colitis was also increased in comparison to the non-targeted formulation of budesonide. In conclusion, matrix tablets with a 1:10 drug-to-dextran ratio with high molecular weight could deliver the drug specifically to the colon and are promising for treatment of ulcerative colitis.


Asunto(s)
Antiinflamatorios/administración & dosificación , Antiinflamatorios/química , Budesonida/administración & dosificación , Budesonida/química , Colitis Ulcerosa/tratamiento farmacológico , Dextranos/administración & dosificación , Dextranos/química , Administración Oral , Animales , Química Farmacéutica/métodos , Colon/efectos de los fármacos , Colon/patología , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Masculino , Peso Molecular , Fenómenos Físicos , Polímeros/administración & dosificación , Polímeros/química , Ratas , Ratas Wistar , Recto/efectos de los fármacos , Recto/patología , Solubilidad , Comprimidos/administración & dosificación , Comprimidos/síntesis química , Comprimidos/química
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