Melting point can not determine the Gibbs free energy directly. So sometimes, the higher melting point polymorph can be meta-stable form at certain temperature.
Thank you SO much for adding that bit about habits- I was struggling to understand the relationship between unit cell and habits and now it is very clear! Carpark analogy helped a lot! Yay!
if the solubility of the stable form is below industry standard, what to choose for formulation ? if you choose a metastable form, it might transition into a stable form with time. What is the best practice ?
Yes, that is a tricky question. I guess the answer depends on whether you get enough bioavailability for your active. If not then a metastable form is an option but I think most companies would go with the stable form and use an alternative solubilisation strategy (eg milling, salt formation or mixing in an amorphous polymer).
Melting point can not determine the Gibbs free energy directly. So sometimes, the higher melting point polymorph can be meta-stable form at certain temperature.
Thank you SO much for adding that bit about habits- I was struggling to understand the relationship between unit cell and habits and now it is very clear! Carpark analogy helped a lot! Yay!
That's good to hear - I like a good analogy
❤❤❤Thank you so much
if the solubility of the stable form is below industry standard, what to choose for formulation ? if you choose a metastable form, it might transition into a stable form with time. What is the best practice ?
Yes, that is a tricky question. I guess the answer depends on whether you get enough bioavailability for your active. If not then a metastable form is an option but I think most companies would go with the stable form and use an alternative solubilisation strategy (eg milling, salt formation or mixing in an amorphous polymer).
@@PharmaDrama : Thank you for response. Your channel was very helpful in brushing up my pharmaceutical crystallization knowledge.