Table III.
Characterization methods for product after melt processing
| Parameter | Methods |
|---|---|
| Size distribution, sphericity, shape | Sieve analysis, digital imaging, laser diffraction (76,188,198) |
| Friability | Friabilator (33,48) |
| Flowability, compactibility, compressibility | FT4 powder rheometer, flow time (funnel), angle of repose, graduated cylinder (tapped/ bulk density, hausner ratio, carr index), texture analyzer (tensile strength profile) (48,169,198) |
| Hardness | Hardness tester, texture analyzer (32, 48,68) |
| Porosity | Mercury porosimeter (142,188,302) |
| True density, specific surface area (BET) | Helium pycnometer (81,158,188) |
| Surface topography and morphology | Scanning electron microscopy (SEM) (179,188) |
| Microstructure |
(Cryogenic) Transmission electron microscopy (TEM) (206) Synchrotron radiation computed microtomography (SRμ-CT) (157) |
| Surface structure | Atomic force microscopy (AFM), stereomicroscopy (179) |
| Coating thickness |
Optical coherence tomography (OCT) |
| Surface polymorphism | Attenuated total reflection fourier transform infrared spectroscopy (ATR-FTIR) (44) |
| Elemental composition & homogeneity | Energy dispersive x-ray microanalysis EDX) (84,306) |
| Chemical distribution & homogeneity | Raman confocal microscopy (raman mapping) (126) |
| Atomic composition & homogeneity | X-ray photoelectron spectroscopy (XPS) (188,366) |
| Buoyancy lag time | Floatability (visualization/counting method) (83,106,133,148,149) |
| Non-invasive, in vivo floating behavior | γ-scintigraphy with radiolabeled technetium (99mTc), radiographic incorporation studies (107) |
| Taste (e.g., bitterness) | Sensory studies with trained or untrained volunteer collective, electronic tongue, short-time dissolution profiles by using disintegration tester (33,196,199,200,203,238) |
| Dissolution | Dissolution tester I/II, data fitting to mathematical kinetic models for controlled release (e.g., zero order) or immediate release (30,57,106,188) |
| In vitro prediction of lipid digestion in vivo | Dissolution with biorelevant medium; in vitro lipolysis with pancreatin, construction of IVIVC-model in case in vivo data is available (9,182,189,190,191) |
| Storage stability at accelerated or intermediate conditions | Evaluation of quality attributes (e.g., dissolution, taste) (43,91,138,139) |