Physical Pharmacy: Amorphous Solids

Amorphous solids aka

Supercooled liquids

Amorphous solids are usually formed through _____ temperature

low temperature

Amorphous molecules when subject to low temperature are arranged in _________

random manner

but since amorphous molecules are tend to form faster, they also break easily hence

faster rate of absorption

Amorphous solids tend to flow when subjected to ________ over time

sufficient pressure

amorphous is _________ soluble than crystalline their counterparts

more soluble

Do not have definite MP and X-ray diffraction pattern

Amorphous solid

Since Amorphous solids Do not have definite MP and X-ray diffraction pattern, they are defined by a ______

glass transition (Tg) temperature

is the temperature where an amorphous material converts from a glass to a supercooled liquid (rubbery state) upon heating

glass transition temperature

amorphous is similar with cubic crystals

isotropic

glass

amorphous solid

pitch and synthetic plastics

amorphous solid

polymers

Amorphous solids

gels

amorphous solids

methods of producing amorphous solids

-Thermodynamic pathway

-Kinetic pathway

thermodynamic pathway aka

Virtification process

kinetic pathway aka

amorphization process

done either by rapidly cooling of a molten liquid (quench-cooling) or by fast evaporation of a solvent form a solution (spray-drying)

Thermodynamic pathway

Most common or preferred method of producing amorphous solids

Thermodynamic pathways

Thermodynamic pathway involves

heating or dissolution

kinetic pathway involves

mechanical processing

done by gradually inducing and increasing defects in the crystal lattice by milling (mechanical process)

Kinetic pathway

kinetic pathway is suitable for

thermolabile drugs (heat-sensitive drugs)