The present study involves preparation and evaluation of floating microspheres with cimetidine as model drug for prolongation of gastric residence time. The microspheres were prepared by the solvent evaporation method using polymers hydroxypropylmethyl cellulose and ethyl cellulose. The shape and surface morphology of prepared microspheres were characterized by optical and scanning electron mic...

Extraction and determination of naproxen from human plasma were performed using Vortex-Assisted Inverted Dispersive Liquid-Liquid MicroExtraction (VA−IDLLME) and High-Performance Liquid Chromatography (HPLC). The parameters affecting extraction recovery such as type and volume of extraction and disperser solvents, pH of sample solution, stirring rate, extraction time and salt addition were ...

The objective of this study was to evaluate the influence of gelator, vegetable oil, stirring speed, and temperature on the physical properties of obtained organogels. They were prepared under varying independent conditions and applying a fractional experimental design. From there a rheological characterization was developed. The physical characterization also included polarized light microscop...

The experiment of the rheocasting-rolling for semi-solid magnesium was carried out on the equipment made by ourselves in our laboratory. Semi-solid AZ91D magnesium slurry was prepared by cooling slope and mchanical sirring The evolution of microstructure under different technological parameters were studied. The results show that the technological parameters have great influence on the microstr...

A multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. For this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 M HCl containing NaCl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

a multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. for this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 m hcl containing nacl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

BACKGROUND A new organodithiophosphorus derivative, namely O-(1,3-Bispiperidino-2-propyl)-4-methoxy phenyldithiophosphonate, was synthesized and then the kinetic behavior of the transport process as a function of concentration, temperature, stirring rate and solvents was investigated. RESULTS The compound 1 was characterized by elemental analysis, IR, 1H and 31P NMR spectroscopies. The transp...

A multiple-unit oral floating system was prepared using the emulsification-solvent diffusion method to prolong the gastric emptying time of theophylline. For this purpose, theophylline, ethyl cellulose and dibutyl phthalate were dissolved in an ethanol/dichloromethane mixture, added to 0.1 M HCl containing NaCl (20%) or saturated theophylline and/or different concentrations of polysorbate 80 an...

AC-driven electrothermal flow is used to enhance the temporal performance of heterogeneous immuno-sensors in microfluidic systems by nearly an order of magnitude. AC electrokinetic forces are used to generate electrothermal flow, which in turn produces a circular stirring fluid motion that enhances the transport of diffusion-limited proteins. This provides more binding opportunities between sus...