mixing Flashcards
when mixing what do you want to achieve
you want to distribute the particles homogenously
importance of mixing is
dose uniformity
what are the boundaries for amount of active compound
+/- 5%
why is dose uniformity important
safety
reproducible during manufacture
what are the different types of mixes
positive
negative
neutral
what is a positive mix
the mix is spontaneous
need energy to separate the mix
miscible fluid
what is a negative mix
segregated and spontaneous
energy needed to mix
immiscible fluid
what is a neutral mix
components neither mix or segregate spontaneously
once mixed the mixture is stable
mechanisms of mixing
liquid
bulk transport
turbulent mixing
molecular diffusion
mechanisms of mixing
solid
convection mixing
shear mixing
diffusion mixing
in mixing of liquid:
- …….….. transport
- …………. mix
- ………….. diffusion
bulk
turbulent
molecular
in mixing of solid:
- ……….. mix
- ………… mix
- …………. mix
convection
shear
diffusive
different spatial arrangements
perfect
random
ordered
what is ordered mix
microionised particles adsorbed on surface of larger carrier particles
what is demixing
reverse process of mixing
