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level: Level 8 - part 1

Questions and Answers List

level questions: Level 8 - part 1

Question	Answer
○ Composed of two-phase system. Ex. Suspension and Emulsion ○ The solute has larger particles and can be sometimes visible with the naked eye. It has distinct layers together with the solvent	DISPERSED SYSTEM
○ Two phase system consisting of finely divided solids that are dispersed in a vehicle (Solid, liquid, or gas) ○ Also termed as mixtures, magmas, gels, and lotions ○ The substance (dispersed phase) is distributed to the vehicle (dispersing phase/medium) ○ The different types of suspensions only differ on the size of the dispersed phase (substance) and how fast they settle upon standing ○ Once mixed with water, their shelf-life would only last for 7 days (not refrigerated) and 14 days (refrigerated)	SUSPENSIONS
Suspensions, once the subst is mixed with water its shelf life would last for __	7 days no ref 14 days with ref
2 TYPES OF DISPERSION	1 Course Dispersion 2 Fine Dispersion
❖Has a dispersed phase particle size of 10-50 um (micrometer) ❖Usually represents the suspensions and emulsions ❖Has a greater tendency to separate from the dispersion medium (vehicle) ❖Upon settling down, the substances are visible since they have bigger particles	Course Dispersion
❖ Has a dispersed phase particle size of 0.5-10 um ❖ Usually represents magmas and gels	Fine Dispersion
Fine Dispersion ADVANTAGES	⚫ Supply drugs to the patient in liquid form, who have difficulty in swallowing ⚫ The dose of the liquid form may be adjusted easily to meet the patient’s requirement ⚫ Suitable dosage form for drug that is insoluble and poorly insoluble (That’s why antibiotics are usually in suspension/tablet/capsule form since they are poorly insoluble and unstable in the presence of aqueous vehicle for extended period of time)
SUSPENSIONS Basic Chemical and Physical Properties	⚫ Settle slowly, easily dispersed with gentle shaking ⚫ Particle size should remain fairly constant in long periods of undisturbed standing, does not cake on settling ⚫ Pour slowly and evenly in the container ⚫ Elegant appearance, resistant to microbial growth, and maintain chemical stability
is preferred because oral preparations should not feel drippy when intaken	micrometer particle size
Particle Size Reduction ❖ Mechanical process of reducing the particle size	Milling
Different machines are used for Milling	1 Hammer Milling 2 Fluid-energy Grinding/Jet Milling/Jet Micronizing 3 Ball Milling 4 Roller Milling
⚫ Grinds the powder by impact and forcing them out in a screen with a mesh size of 4-325 ⚫ Produces a particle size of 10-50 um; Has blades which rotate and reduce the size of the particles into the mesh	Hammer Milling
Produces <25 um through a violent turbulence in high-velocity air Reduces the particle size by particle-to-particle impaction and friction; Has a high-speed air on the pulverizing nozzle installed in the grinding chamber The airflow will drive the large particles toward the perimeter while the small particles move toward the center where they exit through tablet it has air velocity that push out the small particles to the mesh screen	Fluid-energy Grinding/Jet Milling/Jet Micronizing
⚫ Inside the container, it contains a number of steel/ceramic balls in a rotating drum ⚫ The balls will impact the particles and reduce them to 20-200 mesh by both attrition and impact	Ball Milling
⚫ There are 2 or more rollers that revolve at different speeds ⚫ The particles are reduced in mesh of 20-200 by compression and shearing action	Roller Milling
Formulation SUSPENSIONS	1. API – Active product ingredients 2. Dispersing medium 3. Wetting agent 4. Suspending agent 5. Flavorant/Colorant/Preservatives
Active product ingredients which renders the therapeutic effect so usually the API added to the suspension has minimum degree of solubility	API
aqueous or non aqueous and the criteria is that it should not be non toxic and cheap in price and high quality	Dispersing medium
displace the air to fill the small openings of the suspension particles. It will also release the entrap air with the disperse phase is added with dispersing medium	Wetting agent
control the sedimentation rate. Through this agent, the settle down of API is not fast.	Suspending agent