Factors Affecting The Spray Drying Process

3. Does the rate of diffusion change over time? How might this affect your calculated diffusion

2. Explain your observations in detail in terms of concentration gradient, diffusion, osmosis, osmotic pressure, passive transport, and active transport.

In this experiment we observed carmine powder to better understand the concept of Brownian motion and the role of molecular movement in diffusion. The particles continuously moved in a completely random fashion, and the smaller particles moved with more speed than the larger particles.

D. Click Play. Do most of the solvent particles move into or out of the cell? (Hint: Does the cell expand or shrink?) ______________________________________________

1) The relationship between the rate of diffusion, volume and surface area is that the surface area of a subject somewhat correlates with the volume of the object. When the surface area and volume are set up as a ratio, this gives a good idea as to how fast the rate of diffusion will be. The higher surface area to volume ratio, the faster the rate of diffusion. This is because then there is more surfaces to diffuse through and there materials to diffuse, the rate of diffusion is a lot faster. Conversely, when there is a smaller surface area for more molecules to diffuse through, the rate of diffusion will be lower.

4. It is an advantage to choose a solvent that has a large value for kfp because the larger value produces a larger drop in freezing point. Having a larger drop in freezing point is an advantage because it allows for the data to be more easily read. A large drop in freezing point also produces more significant figures and more significant figures means the calculated molar mass is more precise.

Manufacturing theophylline formulations come with challenges for both the anhydrous and hydrate. For the anhydrous form, a study showed that the wet granulation of theophylline anhydrous in conjunction with microcrystalline cellulose, led to the formation of the monohydrate form of the drug. This is significant because the monohydrate has slower dissolution than the anhydrous form of theophylline. Thus the method of manufacture is highly important as the study showed directly compressed pellets had better dissolution profiles. Also it shows the importance of the choice of excipients as pellets manufactured via wet granulation in the absence of microcrystalline cellulose showed similar release to that of directly anhydrous theophylline.

The following hypothesis was made in regard to effect of the concentration gradient on the rate of diffusion: The higher the concentration gradient, the faster the rate of diffusion.

The kinetic energy causes the particles to vibrate and move randomly – moving around the area in which they are held. The random movement causes the particles to distribute randomly around the area. The higher concentrated solution has more particles that can move across the membrane compared to the lower, producing a net movement down the concentration gradient.

The purpose of this lab report is to synthesize luminol and then test its chemiluminescent properties. 5-nitro-2,3-dihydrophtalazine-1,4-dione was reduced using sodium hydrosulfite in a solution of 3 M sodium hydroxide in water to form luminol. The product was then used to chemically generate light by reacting luminol with 3 M sodium hydroxide, hydrogen peroxide, and potassium ferricyanide. The reaction created a bright, blue light emission. From glow sticks to revealing remnants of blood samples in crime scene investigations, luminol, C8H7N3O2, has a wide variety of real world applications.

Nanocrystals are made up of drug with only little amount of surfactant (below critical micelle concentration (CMC)) to stabilize formulation [14]. Most of the nanoparticles are made up of large amount of excipients which is not the case with nanocrystals as most of the part is only the drug. Besides lower amount of stabilizers makes toxicity issues associated with nanosuspensions negligible and offers ease of scale-up and better physical stability compared to amorphous form [15, 16]. Different methods are classified as top-down (high pressure homogenization, media milling, and sonication) and bottom-up techniques (nanoprecipitation) for effective production of Nanocrystals [17]. Development of nanocrystal based formulation of risperidone can be advantageous to tackle the problem of poor water solubility. Numerous solidification techniques are used to increase physical stability of nanosuspensions as spray drying, lyophilization and many more based upon the properties of drug and characteristics of final formulation. Amongst all these techniques lyophilization is used predominantly for nanosuspension solidification.

Hypothesis: If the solvent is denser, than the time it takes the sugar to dissolve will decrease.

b) If 5mL of water were added for every 1g of crude product then one of two things would happen; the solid would not dissolve or the impurities would still be present within the product. The solvent is used to dissolve all the impurities of the crude product and if less solvent is available, the impurities would remain within the product.

The water released from the clouds in the form of rain, sleet, snow or hail is called precipitation. For the formation of precipitation millions of droplets coalesce into drops large enough so as to sustain themselves during their descent. Two mechanisms have been put forth to explain this phenomenon, which are explained as follows:

The optimal solvent that will maximize the