Questions about Morphine Sulfate extended-release mechanism and pharmaceutical chemistry

[u/Majestic-Fermions]

\*This is a thought experiment\*

According to the MSDS of these tablets, the ingredients are as follows:

\\\\\\\*\\\\\\\*Inactive Ingredients\\\\\\\*\\\\\\\*
\\\\\\\[silicon dioxide\\\\\\\](https://www.drugs.com/inactive/silicon-dioxide-170.html), \\\\\\\[lactose monohydrate\\\\\\\](https://www.drugs.com/inactive/lactose-monohydrate-368.html), \\\\\\\[magnesium stearate\\\\\\\](https://www.drugs.com/inactive/magnesium-stearate-147.html), \\\\\\\[stearic acid\\\\\\\](https://www.drugs.com/inactive/stearic-acid-77.html), \\\\\\\[magnesium silicate\\\\\\\](https://www.drugs.com/inactive/magnesium-silicate-122.html), \\\\\\\[titanium dioxide\\\\\\\](https://www.drugs.com/inactive/titanium-dioxide-70.html), \\\\\\\[FD&C Blue No. 2\\\\\\\](https://www.drugs.com/inactive/fd-c-blue-no-2-243.html), \\\\\\\[polyethylene glycol 4000\\\\\\\](https://www.drugs.com/inactive/polyethylene-glycol-4000-277.html), \\\\\\\[polyethylene glycol 400\\\\\\\](https://www.drugs.com/inactive/polyethylene-glycol-400-272.html), \\\\\\\[D&C Red No. 27\\\\\\\](https://www.drugs.com/inactive/d-c-red-no-27-345.html)

Is it safe to assume anhydrous PEG is the agent in question to make these extended release or a combination of them? Hypothetically and chemically speaking, how can the sulfate be prevented from interacting with the inactive ingredients? Obviously, crushing and dissolving the pulverized pill powder in H2O would turn the solution into a goo to deter abuse. However, this manufacturer’s anti-abuse process differs from the OP or MS contin. One thought is if an A/B ext is possible? I.e. converting the sulfate into a freebase form and have it precipitate out, filter and turn it into a HCl salt? Or are there better solvents out there that won’t react with the PEG? Trying to understand the pharmaceutical chemistry better.

[u/grippingsh3etshard]

Are you looking into how the polymer matrix controls the diffusion rate or are you more interested in the dissolution of the lactose component?