Statistical optimization and in-vitro evaluation of hollow microcapsules of an anti-hypertensive agent.

The present work attempts to formulate and evaluate hollow microcapsules of an antihypertensive drug--ramipril, which will remain in vicinity of absorption site. The emulsion diffusion solvent evaporation method was employed for preparation of microspheres using Eudragit E100. Glycerol monostearate and sodium lauryl sulfate were used as surfactants, which showed good effect of film integrity. The different proportion of Eudragit E100 and ramipril at varying speed were employed for formulating hollow microspheres using 3(2) full factorial design. The formulated microspheres were subjected to evaluation of various parameters such as particle size analysis using motic microscope, drug loading efficiency and in vitro drug release. The main effect plot showed negative impact of polymer concentration and drug complex concentration, whereas positive impact of rotation speed on the % release of drug and drug encapsulation efficiency. The optimized batch of microcapsules was formulated as a hard gelatine capsule dosage form containing loading (plain drug) as well as sustained fraction of drug in form of microcapsules. It was found that dosage form also showed good in vitro release profile.

Nanoparticles for triggering and regulation of immune response of vaccines: perspective and prospective.

Nanoparticles mediated vaccine delivery is an emerging technology and considered as better adjuvant for delivering vaccines when compared to conventional delivery system. The purpose of this delivery system is to provide simple stable formulation that elicits lifelong immunity preferably with single shot. In line to develop the biodegradable polymer vaccine delivery system it is necessary to understand about the nature of polymer, type of antigen to be encapsulated, broad idea about immunological sketch. In this review, we attempt to provide an overview about the nano particle vaccine delivery system and interaction between nano particle and the immune system.

Preparation and statistical optimization of alginate based stomach specific floating microcapsules of simvastatin.

The present study involves preparation and characterization of floating microcapsules with simvastatin as model drug for prolongation of gastric residence time. The main objective is to improve solubility of simvastatin beta-CD complex (1:2) by co-precipitation method and then to deliver the same in sustained release dosage form. Sustained-release simvastatin microcapsules were prepared by the ionic gelation technique, using carbopol 941 as swellable floating polymer. A 3(3) full factorial design was used to study the effect of polymer concentration, drug complex and sodium alginate by plotting main effect plot and 3D surface plots. The formed microcapsules were subjected to various evaluation tests such as drug encapsulation efficiency, in vitro drug release and surface morphology by scanning electron microscopy. Powdered X-ray diffractometry and FTIR were used to investigate the complexation of simvastatin in the microcapsules. As the carbopol 941 is self swellable polymer, immediate floating was observed. The in vitro release studies and floating behavior were performed in HCI buffer of pH 1.2. The release profile and dissolution kinetic showed that drug release from the microcapsules follows zero order kinetics. It was concluded from the present investigation that porous carbopol 941 microcapsules are promising sustained release system as well as stomach specific carriers for delivery of simvastatin.

Microcapsules and transdermal patch: a comparative approach for improved delivery of antidiabetic drug.

Glibenclamide (GL)-loaded microcapsules (MC) and transdermal patches (TDP) were formulated and in vitro and in vivo parameters compared to find out the best route of drug administration. The formulation TDP1 having a drug-polymer ratio 1:1 showed comparatively higher GL release and better permeation across mice skin (p < 0.05). From the comparative study, it was concluded that the transdermal system of GL produced better improvement compared to oral microcapsule administration (p < 0.05). The transdermal system exhibited comparatively slow and continuous supply of GL at a desired rate to systemic circulation avoiding metabolism, which improved day-to-day glycemic control in diabetic subjects. Transdermal system of GL exhibited better control of hyperglycemia and prolonged plasma half-life by transdermal systems (9.6 +/- 1.2 h) in comparison with oral microcapsule (5.84 +/- 2.1 h), indicating that the drug, when administered by transdermal systems, will remain in the body for a longer period. From the glucose tolerance test, transdermal route effectively maintained the normoglycemic levels in contrast to the oral group (MC1), which produced remarkable hypoglycemia ranging from -12.6 +/- 2.1% to -18 +/- 2.3%. The significantly high (p < 0.05) area under the curve values observed with transdermal system (1,346.2 +/- 92.3 ng ml(-1) h(-1)) also indicate increased bioavailability of the drug from these systems compared to the oral route (829.8 +/- 76.4 ng ml(-1) h(-1)).