Formulation and Quality – Chemical
2019 PharmSci 360
As a solvent-free continuous process, twin-screw melt granulation (TSMG) is an emerging technique for improving the flowability and tabletability of powder blends. During TSMG, thermal binders melt and are spread over API particles under distributive and dispersive mixing by rotating crews. Using acetaminophen (APAP, API) and hydroxypropyl cellulose (Klucel EXF, binder), the effect of Klucel level on the tabletability of melt-extruded granules was investigated. APAP granules containing 5%-15% Klucel could be compressed into tablets with tensile strength up to 3.5 MPa. However, 20% Klucel content led to considerably lower tabletability, attributable to high mechanical strength of APAP granules. The formation of strong granules and the loss of tabletability are known as "over-granulation". The over-granulation in TSMG was attributed to thick HPC scaffold and low porosity in 20% Klucel granules. As a result, these granules underwent a lower degree of fracture under compression and more extensive elastic recovery during decompression.