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1.
Braz. j. pharm. sci ; 51(3): 591-605, July-Sept. 2015. tab, graf
Article in English | LILACS | ID: lil-766309

ABSTRACT

The work was aimed at developing novel enteric coated HPMC capsules (ECHC) plugged with 5 Florouracil (5-FU) loaded Microsponges in combination with calcium pectinate beads. Modified quasi-emulsion solvent diffusion method was used to formulate microsponges based on 32 factorial design and the effects of independent variables (volume of organic solvent and Eudragit RS100 content) on the dependent variables (Particle size, %EE & % CDR) were determined. The optimized microsponges (F4) were characterized by SEM, PXRD, TGA and were plugged along with calcium pectinate beads in HPMC capsules and the HPMC capsules were further coated with enteric polymer Eudragit L 100 (Ed-L100) and/ or Eudrgit S 100 (Ed-S 100) in different proportions. In vitro release study of ECHC was performed in various release media sequentially SGF for 2 h, followed by SIF for the next 6 h and then in SCF (in the presence and absence of pectinase enzyme for further 16 h). Drug release was retarded on coating with EdS-100 in comparison to blend of EdS-100: EdL-100 coating. The percentage of 5-FU released at the end of 24 h from ECHC 3 was 97.83 ± 0.12% in the presence of pectinase whereas in control study it was 40.08 ± 0.02% drug. The optimized formulation was subjected to in vivo Roentgenographic studies in New Zealand white rabbits to analyze the in vivo behavior of the developed colon targeted capsules. Pharmacokinetic studies in New Zealand white rabbits were conducted to determine the extent of systemic exposure provided by the developed formulation in comparison to 5-FU aqueous solutions. Thus, enteric coated HPMC capsules plugged with 5-FU loaded microsponges and calcium pectinate beads proved to be promising dosage form for colon targeted drug delivery to treat colorectal cancer.


O trabalho teve como objetivo o desenvolvimento de novas cápsulas com revestimento entérico HPMC (ECHC) conectadas com microesponjas carregadas com fluoruracila (5-FU) em combinação com grânuos de pectinato de cálcio. O método de difusão de solvente modificado quasi-emulsão foi usado para formular microesponjas com base no planejamento fatorial 32 e determinaram-se os efeitos das variáveis independentes (volume de solvente orgânico e conteúdo Eudragit RS100) sobre as variáveis dependentes (tamanho de partícula, EE% e % CDR). As microesponjas otimizadas (F4) foram caracterizadas por SEM, PXRD, TGA e ligadas aos grânulos de pectinato de cálcio em cápsulas de HPMC e estas foram, ainda, revestidas com polímero entérico Eudragit L 100 (Ed-L100) e/ou Eudrgit S 100 (Ed S 100) em diferentes proporções. No estudo de liberação in vitro de ECHC foi realizada em vários meios de liberação sequencial SGF durante 2 h, seguido de SIF para as próximas 6 h, e, em seguida, em SCF (na presença e na ausência de enzima pectinase por mais 16 h). A liberação do fármaco foi retardada em revestimento com a EDS-100, em comparação com mistura de EDS-100: EDL-100, de revestimento. O percentual de 5-FU liberado de ECHC 3 ao final de 24 h foi 97,83 ± 0,12% em presença de pectinase, enquanto que para o controle foi de 40,08 ± 0,02% do fármaco. A formulação otimizada foi submetida a estudos Roentgenográficos in vivo, em coelhos brancos Nova Zelândia, para analisar o comportamento das cápsulas desenvolvidas direcionadas ao cólon. Os estudos de farmacocinética em coelhos brancos da Nova Zelândia foram conduzidos para determinar a extensão da exposição sistêmica propiciada pela formulação desenvolvida, em comparação com solução aquosa de 5-FU. Assim, cápsulas entéricas de HPMC revestidas e conectadas com microesponjas carregadas com 5-FU e grânulos de pectinato de cálcio se mostraram promissoras como formulação para liberação do fármaco no cólon no tratamento do câncer colorretal.


Subject(s)
Rabbits , Tablets, Enteric-Coated/analysis , Capsules/pharmacokinetics , Colonic Neoplasms/classification , Hypromellose Derivatives , Chemistry, Pharmaceutical , Fluorouracil/analysis
2.
Indian J Med Sci ; 2010 Apr; 64(4) 163-176
Article in English | IMSEAR | ID: sea-145502

ABSTRACT

Objective: To screen the Polyherbal preparation for anti-diabetic activity in rats. Materials and Methods: The blood glucose lowering activity of the Polyherbal preparation-I (1:1:1 of Wheat germ oil, Coriandrum sativum and Aloe vera) was studied in normal rats after oral administration at doses of 1.0 and 2.0 ml/kg and Polyherbal preparation-I, II (Wheat germ oil, fresh juice of C. sativum and Aloe vera in the ratio of 2:2:1), and III (Wheat germ oil, fresh juice of C. sativum and Aloe vera in the ratio of 1:2:2) on alloxan-induced diabetic rats, after oral administration at doses of 1.0 and 2.0 ml/kg. Blood samples were collected from the tail vein method at 0, 0.5, 1, 2, 4, 8, 12, and 24 h in normal rats and in diabetic rats at 0, 1, 3, 7, 15, and 30 days. Blood plasma glucose was estimated by the GOD/POD (glucose oxidase and peroxidase) method. The data was compared statistically using the one-way ANOVA method followed by the Dunnett multiple component test. Statistical significance was set at P<0.05. Results: The Polyherbal preparation-I produced significant (P<0.05) reduction in the blood glucose level of normal rats and Polyherbal preparation-I, II, and III produced significant (P<0.01) reduction in the blood glucose level of diabetic rats during 30 days study and compared with that of control and Glibenclamide. Conclusion: The Polyherbal preparation-I showed a significant glucose lowering effect in normal rats and Polyherbal preparation-I, II, and III in diabetic rats. This preparation is going to be promising anti-diabetic preparation for masses; however, it requires further extensive studies in human beings.


Subject(s)
Alloxan/administration & dosage , Alloxan/pharmacokinetics , Animals , Blood Glucose/blood , Diabetes Mellitus/chemically induced , Diabetes Mellitus, Experimental/chemically induced , Disease Models, Animal , Plant Preparations , Rats
3.
Article in English | IMSEAR | ID: sea-139809

ABSTRACT

Aim: The aim of this study to develop the controlled delivery of combination drug(s) to periodontal pocket. Materials and Methods: In the present investigation mucoadhesive gel formulations were prepared using carboxy methylcellulose (CMC), methylcellulose (MC), hydroxyethylcellulose (HEC), polyvinylpirrolidone (PVP), polycarbophil (PC), and poloxamer. Each formulation was characterized in terms of polarizing light microscopy, gelation, gel melting, hardness, compressibility, adhesiveness, cohesiveness, syringeability, adhesion to a mucin disk, rheological studies, drug release, and antibacterial activities. Addition of CMC and PVP to the gel favored hexagonal phase formation. The gelation temperature was decreased linearly with an increasing concentration of drug(s), whereas, the melting temperature increased with the concentration of drug(s). Increasing the concentrations of each polymeric component significantly increased formulation hardness, compressibility, adhesiveness, mucoadhesion, and syringeability, yet a decreased cohesiveness. Increased time of contact between the formulation and mucin significantly increased the required force of detachment. Drug release from all formulations was non-diffusion controlled and significantly decreased as the concentration of the polymer was increased, due to the concomitant increased viscosity of the formulations and the swelling kinetics of PC, following contact with the dissolution fluid. Result: Antibacterial studies revealed that a gel with 30% HEC had a growth inhibition zone on agar with all three strains. Conclusion: Formulations containing HEC exhibited superior physical characteristics for improved drug delivery to the periodontal pocket and are now the subject of long-term clinical investigations.


Subject(s)
Adhesiveness , Anti-Infective Agents, Local/administration & dosage , Biomechanical Phenomena , Compressive Strength , Delayed-Action Preparations/administration & dosage , Dental Stress Analysis , Doxycycline/administration & dosage , Drug Combinations , Drug Design , Escherichia coli/drug effects , Gels/chemistry , Hardness , Materials Testing , Metronidazole/administration & dosage , Microbial Sensitivity Tests , Periodontal Pocket/drug therapy , Porphyromonas gingivalis/drug effects , Rheology , Staphylococcus aureus/drug effects
4.
Braz. j. pharm. sci ; 45(4): 829-840, Oct.-Dec. 2009. tab, ilus
Article in English | LILACS | ID: lil-543679

ABSTRACT

The present study investigated a novel extended release system of promethazine hydrochloride (PHC) with acrylic polymers Eudragit RL100 and Eudragit S100 in different weight ratios (1:1 and 1: 5), and in combination (0.5+1.5), using freeze-drying and spray-drying techniques. Solid dispersions were characterized by Fourier-transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), Powder X-ray diffractometry (PXRD), Nuclear magnetic resonance (NMR), Scanning electron microscopy (SEM), as well as solubility and in vitro dissolution studies in 0.1 N HCl (pH 1.2), double-distilled water and phosphate buffer (pH 7.4). Adsorption tests from drug solution to solid polymers were also performed. A selected solid dispersion system was developed into capsule dosage form and evaluated for in vitro dissolution studies. The progressive disappearance of drug peaks in thermotropic profiles of spray-dried dispersions were related to increasing amount of polymers, while SEM studies suggested homogenous dispersion of drug in polymer. Eudragit RL100 had a greater adsorptive capacity than Eudragit S100, and thus its combination in (0.5+1.5) for S100 and RL 100 exhibited a higher dissolution rate with 97.14 percent drug release for twelve hours. Among different formulations, capsules prepared by combination of acrylic polymers using spray-drying (1:0.5 + 1.5) displayed extended release of drug for twelve hours with 96.87 percent release followed by zero order kinetics (r²= 0.9986).


O presente trabalho compreendeu estudo de um novo sistema de liberação prolongada de cloridrato de prometazina (PHC) com polímeros acrílicos Eudragit RL100 e Eudragit S100 em diferentes proporções em massa (1:1 e 1:5) e em combinação (0,5+1,5), utilizando técnicas de liofilização e de secagem por aspersão As dispersões sólidas foram caracterizadas por espectrofotometria no infravermelho por transformada de Fourier (FT-IR), calorimetria diferencial de varredura (DSC), difratometria de raios X (PXRD), Ressonância Magnética Nuclear (RMN), microscopia eletrônica de varredura (SEM) e, também, por estudos de solubilidade e de dissolução in vitro em HCl 0,1 N (pH 1,2), água bidestilada e tampão fosfato (pH 7,4). Realizaram-se, também, testes de adsorção da solução do fármaco nos polímeros sólidos. Desenvolveu-se sistema de dispersão sólida exclusiva dentro das cápsulas, que foi avaliado por meio de estudos de dissolução in vitro. Relacionou-se o desaparecimento progressivo de picos do fármaco em perfis termotrópicos de dispersões secas por spray à quantidade aumentada de polímero, enquanto os estudos de SEM sugeriram dispersão homogênea do fármaco no polímero. O Eudragit RL100 apresentou maior capacidade de adsorção do que o Eudragit S100 e, dessa forma, a combinação de (0,5+1,5) para S100 e para RL100 mostrou taxa de dissolução maior, com liberação de 94,17 por cento de fármaco em 12 horas. Entre as várias formulações, as cápsulas preparadas pela combinação de polímeros acrílicos utilizando secagem por aspersão (0,5+1,5) apresentou liberação prolongada do fármaco em 12 horas, com 96,78 por cento de liberação, seguindo cinética de ordem zero (r² = 0,9986).


Subject(s)
Hydrochloric Acid/pharmacokinetics , Chemistry, Pharmaceutical , Delayed-Action Preparations , Polymers/pharmacokinetics , Organic Chemistry Phenomena , Promethazine/pharmacokinetics , Drug Evaluation , Freeze Drying , Pharmaceutical Preparations
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