Things we should just know Flashcards
What are the two natural Gelling agents
Alginic Acid
Tragacanth
What are the two semi-synthetic- cellulose derivatives (Type of gelling agents)
Methylcellulose (Runny)
HPMC (Thicker, time release)
What are the synthetic Gelling agents
Carbomers *Neutralizer, Thickener
Poloxamers Absorbing, mostly pharmacy compound **Reverse thermal
What does the DLVO theory describe?
Estimating the stability of hydrophobic solutions
With regard to DLVO theory what forces of attraction predominates the repulsive forces?
Small distance (Primary minimum) and long distance (Secondary attraction)
Three ways of stabilizing a dispersed system
Change viscosity
Add buffer to maintain stability
Add Electrolytes for compatibility
What are the external phase Polar Liquids (Medium)
Water, Simple Syrup, Cherry
What are the external phase non-polar liquids (Medium)
Oils,Fatty Esters, hydrocarbons
What are the properties of structured vehicles in solutions? (High and low concentration)
They serve as protective colloids at low concentration while at high concentrations they are viscous inducing agents
What are the three flocculating agent categories we discussed with regards to suspensions
Electrolytes
Ionic Surfactants
Polymeric flocculating agents
What is an issue with the usage of polysaccharides as a viscosity modifier?
They increase the susceptibility to microbial growth
Acacia gum
Tragacanth
Alginates
What are the water soluble cellulose derivatives viscosity modifiers?
Methylcellulose
Microcrystalline cellulose
What are the Hydrated silicates viscosity modifiers?
Bentonite
What are the Acrylic acid polymer viscosity modifiers?
Carbopol/Carbomer
What are the inorganic Colloids?
Milk of magnesia Two phase system
What are the organic colloids?
Single phase system,Carbomer
What is alginic acid?
Natural gelling agent that is prone to microbrial growth,
What is Tragacanth?
Natural gelling agent that is used fora stable PH
What is Methylcellulose?
Semi-synthetic cellulose derivative that maintains viscosity over wide ph range,
This makes thinner gels htough and hydrates in HOT water
What is HPMC?
Makes thick boi gels
Semi-synthetic cellulose derivative gelling agent
What is Carbomers or Carbopol?
Synthetic gelling agent that thickens AND requires PH neutralizers
When it gets thick it gets ph spicy
What is Poloxamers?
Synthetic gelling agent that forms reverse thermal gels!
What are colloidal gold, sulfur, and silver examples of?
Lyophobic colloids
What are the 5 Viscosity modifiers for suspensions?
PWHAC
Polysaccharides
Water soluble cellulose derivatives
Hydrated Silicates
Acrylic acid polymers
Colloidal silicin dioxide
Types of bioreactors
Liquid and solid state
Low concentrations of phospholipids and surfactants have been shown to?
Extert a fibrillation-inhibitory effect
What is the sweeter than sucrose value for cyclamate?
30 times
What is the sweeter than surcose value for saccharin?
300x
What is less sweet then sugar?
Sorbitol, mannitol, aspartame
What is the sweeter than sucrose value for stevia?
200x
