ABSTRACT
Objective: The aim of this study is to prepare floating hollow microspheres encapsulating Sorafenib (SFN) to enhance its oral bioavailability. Methods: Gastro-floating hollow adhesive microspheres containing SFN were produced by using an emulsion solvent evaporation technique with ether and ethanol as solvents. Ethyl cellulose and carbopol 934P were used as the encapsulating carriers. The effects of formulation parameters like, solvent volume ratio, and drug to polymer ratio (D: P ratio), encapsulation efficiency percentage EE%, floating percentage, and release of SFN after 12 h (Rel12) were investigated and analyzed using a (32) full factorial design. Results: The floating percentage of the microspheres was found to be 76.5%. The in vitro drug release from these hollow microspheres followed the Higuchi model equation. The in vivo results showed that approximately 1.96-fold improvement in the relative bioavailability of the microspheres compared with that of the commercial tablet. Conclusion: The results demonstrate that the hollow microspheres with good gastro-floating ability are a promising delivery system to enhance SFN bioavailability.
ABSTRACT
Current study is to develop the colon targeted matrix tablet using the natural polysaccharide sterculia gum as carrier and model drug ciprofloxacin HCl. The matrix tablets were prepared by wet granulation technology using the various proportions of sterculia gum with carbopol 934 P, sterculia gum and ethyl cellulose polymer blends. Gra-nules of all formulations were evaluated for rheological, post compressional properties and in vitro dissolution study in different pH buffers of pH 1.2 , pH 7.4 , pH 6.8 (saline phosphate buffer) without and with 4% rat cecal content in order to mimic GIT condition . Formulation SGC2 to SGC4 and SGE7 to SGE9 has released 13.6% to 38.9% in the initial 5h and released more amount of drug in stomach and small intestine than colon. Formulation SGC5 containing 45% of sterculia gum and 25% carbopol 934 p and Formulation SGE10 containing 45% of sterculia gum and 25% ethyl cellulose has released minimum 10.91 % to 13.04 % in the initial 5h and sustained the drug release up to 24 h and at the end of study released 75% to 79.99%. Formulations with 4% rat cecal content at the end of 24 h study drug released is 90.44% to 95.33% indicating higher amount of drug release is due to enzymatic break down of sterculia gum in the matrix tablet. Hence the above results conclude that the formulation SGC5 and SGE10 are potential in targeting the drug to colon to treat irritable bowel disease.
ABSTRACT
Current study is to develop the colon targeted matrix tablet using the natural polysaccharide sterculia gum as carrier and model drug ciprofloxacin HCl. The matrix tablets were prepared by wet granulation technology using the various proportions of sterculia gum with carbopol 934 P, sterculia gum and ethyl cellulose polymer blends. Gra-nules of all formulations were evaluated for rheological, post compressional properties and in vitro dissolution study in different pH buffers of pH 1.2 , pH 7.4 , pH 6.8 (saline phosphate buffer) without and with 4% rat cecal content in order to mimic GIT condition . Formulation SGC2 to SGC4 and SGE7 to SGE9 has released 13.6% to 38.9% in the initial 5h and released more amount of drug in stomach and small intestine than colon. Formulation SGC5 containing 45% of sterculia gum and 25% carbopol 934 p and Formulation SGE10 containing 45% of sterculia gum and 25% ethyl cellulose has released minimum 10.91 % to 13.04 % in the initial 5h and sustained the drug release up to 24 h and at the end of study released 75% to 79.99%. Formulations with 4% rat cecal content at the end of 24 h study drug released is 90.44% to 95.33% indicating higher amount of drug release is due to enzymatic break down of sterculia gum in the matrix tablet. Hence the above results conclude that the formulation SGC5 and SGE10 are potential in targeting the drug to colon to treat irritable bowel disease.
ABSTRACT
The present work aims at the development and evaluation of Floating matrix tablets of Cefpodoxime Proxetil were undertaken to prolong gastric residence time. A visible Spectrophotometric method has been employed for the estimation of Cefpodoxime Proxetil at 263 nm and Beer’s law is obeyed in the concentration range of 5-40 μg/ml. Total 7 formulations (B1-B7) were prepared using guargum with carbopol 934P was used in different concentrations. Fourier transform Infrared spectroscopy confirmed the absence of any drug/polymers/excipients interactions. The tablets were prepared by direct compression technique, using polymer such as hydroxy propyl methyl cellulose (HPMC K4M), guargum and carbopol 934P in different combinations with other standard excipients like sodium bicarbonate and lactose. Tablets were evaluated for physical characterization viz. hardness, friability, swelling index, floating capacity, thickness and weight variation. Further tablets were evaluated in-vitro drug release for 12 hr. The effect of polymer concentrations on buoyancy and drug release pattern was also studied. In-vitro drug release mechanism was evaluated by PCP V-3 software. Carbopol 934P had a negative effect on the floating properties also decreased the drug release. A lesser FLT and a prolonged floating duration could be achieved by varying the amount of effervescent and using different polymer concentrations. The entire matrix tablets showed significantly greater swelling index, exhibited controlled and prolonged drug release profiles and some floated over the dissolution medium for more than12 hr. The paddle speed affected the floating lag time and floating duration it had a negative effect on the floating properties. The optimized formulation followed the higuchi release model and showed non-fickian diffusion mechanism. It also showed no significant change in physical appearance, drug content, floatability or in-vitro dissolution pattern after storage at 45 oC at 75 % RH for three months.
ABSTRACT
Pharmaceutical formulations containing poloxamer 407 (P407), Carbopol 934P (C934P) or gelatin (GELA), with ethanolic propolis extract (PE), were designed for the treatment of oral mucosal diseases. PE was produced and its quality was assessed by measuring its specific gravity, pH, weight of dry residue and total flavonoid content. Monopolymeric and binary polymeric formulations were prepared and their gelling temperature (Tsol/gel), pH, continuous flow rheology and mucoadhesion were studied. PE exhibited good quality and the formulations were easy to prepare and showed a wide range of consistency. Most of the formulations showed thermoresponsive behaviour and only those containing 15% P407, plus 0.20% C934P or 1.0 % GELA, displayed Tsol/gel suitable for application to the oral mucosa. Monopolymeric formulations, containing C934P or GELA, and binary formulations exhibited pseudoplastic flow and low degrees of thixotropy. Monopolymeric formulations containing P407 exhibited pseudoplastic flow and rheopexy. The mucoadhesive properties of the systems could not be assessed. Fragments of formulation were found to remain stuck to parts of the mucin disc, owing to cohesive failure of the samples and of the sample/mucin interface. The data obtained on these formulations indicate a potentially useful role in the treatment of oral mucosal diseases
Formulações farmacêuticas contendo poloxamer 407 (P407), Carbopol 934P (C934P) ou gelatina (GELA), e extrato de própolis (EP) foram desenvolvidos para o tratamento de doenças da mucosa oral. EP foi produzido e sua qualidade foi avaliada quanto ao resíduo seco e ao teor de flavonóides totais. Formulações monopoliméricas e poliméricas binárias foram produzidas e a temperatura de gelificação (Tsol/gel), o pH, a reologia, assim como a mucoadesão das mesmas foram avaliados. O EP apresentou boa qualidade, as preparações foram fáceis de produzir e apresentaram uma ampla variação de consistência. A maioria das preparações apresentou comportamento de resposta térmica e apenas as formulações contendo 15% P407 e 0,20% C934P ou 1,0% GELA apresentaram Tsol/gel adequada para a administração na mucosa oral. Formulações monopoliméricas, contendo C934P ou GELA, e binárias exibiram comportamento de fluxo pseudoplástico e baixo grau de tixotropia. Formulações monopoliméricas de P407 exibiram fluxo pseudoplástico e reopexia. As propriedades mucoadesivas dos sistemas não puderam ser avaliadas. Fragmentos de formulações foram encontrados aderidos em alguns lugares do disco de mucina devido à falha de coesão das amostras e da interface amostra/mucina. Os resultados obtidos com essas formulações indicam a utilidade das mesmas no tratamento de doenças da mucosa oral.