Solvent-Assisted Secondary Drying of Spray-Dried Polymers.
Pharm Res
; 37(8): 156, 2020 Jul 31.
Article
in En
| MEDLINE
| ID: mdl-32737611
ABSTRACT
PURPOSE:
The purpose of this work is to introduce solvent-assisted secondary drying, a method used to accelerate the residual solvent removal from spray dried materials. Spray-drying is used to manufacture amorphous solid dispersions, which enhance the bioavailability of active pharmaceutical ingredients (APIs) with low aqueous solubility. In the spray-drying process, API and excipients are co-dissolved in a volatile organic solvent, atomized into droplets through a nozzle, and introduced to a drying chamber containing heated nitrogen gas. The product dries rapidly to form a powder, but small amounts of residual solvent (typically, 1 to 10 wt%) remain in the product and must be removed in a secondary-drying process. For some spray-dried materials, secondary drying by traditional techniques can take days and requires balancing stability risks with process time.METHODS:
Spray-dried polymers were secondary dried, comparing the results for three state-of-the-art methods that employed a jacketed, agitated-vessel dryer (1) vacuum-only drying, (2) water-assisted drying, or (3) methanol-assisted drying. Samples of material were pulled at various time points and analyzed by gas chromatography (GC) and Karl Fischer (KF) titration to track the drying process.RESULTS:
Model systems were chosen for which secondary drying is slow. For all cases studied, methanol-assisted drying outperformed the vacuum-only and water-assisted drying methods.CONCLUSIONS:
The observation that methanol-assisted drying is more effective than the other drying techniques is consistent with the free-volume theory of solvent diffusion in polymers.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Polymers
/
Solvents
/
Desiccation
/
Volatile Organic Compounds
Language:
En
Journal:
Pharm Res
Year:
2020
Document type:
Article
Affiliation country:
United States