Influence of Plasticizers and Drugs on the Physical-Mechanical Properties of Hydroxypropylcellulose Films Prepared by Hot Melt Extrusion

Abstract

Hydroxypropylcellulose (HPC) films containing drugs or hydrophilic or hydrophobic plasticizers were prepared by a hot melt extrusion process. Polyethylene glycol 8000 (PEG 8000) 2%, triethyl citrate (TEC) 2%, acetyltributyl citrate (ATBC) 2%, and polyethylene glycol 400 (PEG 400) 1% were the plasticizing agents studied. In addition, either hydrocortisone (HC) 1% or chlorpheniramine maleate (CPM) 1% was incorporated into the films as a model drug. The physical-mechanical properties of the films that were investigated included tensile strength (TS), percentage elongation (%E), and Young's modulus (YM). Differential scanning calorimetry (DSC) was utilized to determine glass transition temperatures (Tg's). These parameters were studied as a function of time and temperature. The glass transition temperatures initially decreased with the inclusion of the drugs and plasticizers. However, after 6 months aging, films containing PEG 400 and HC showed a marked increase in Tg. The films containing PEG 400 showed physical-mechanical instability in all parameters studied. All extruded films exhibited a marked decrease in TS in contrast to a large increase in %E when testing was performed perpendicular to flow versus in the direction of flow. In addition, a consistent film of HPC in the absence of drugs or plasticizers could not be extruded due to the excessive stress on the equipment. Although the theoretical percentage of CPM on aging remained fairly constant over the processing temperature ranges in this study, the HC levels remaining in the extruded films during storage were a function of time and temperature.

Oral immunization of rhesus macaques with adenoviral HIV vaccines using enteric-coated capsules

“…In order to ensure the adhesion of the enteric coating polymer dispersion, the amount of plasticizer (TEC) was adjusted to manufacturer recommended specifications for enteric coatings (Table 1). Because pharmaceutical acrylic polymers are brittle, fragile and exhibit strong adhesiveness [52], the addition of plasticizers and glidants, such as talc (Table 1), ensures the favorable elasticity of the coatings by decreasing polymer tensile strength [52,53], lowering the film forming temperature without adverse mechanical effects [54][55][56][57][58], and facilitating GI transit through mucosal surfaces by avoiding polymer dispersion agglomeration.…”

Taste Masking of Griseofulvin and Caffeine Anhydrous Using Kleptose Linecaps DE17 by Hot Melt Extrusion

“…They found that all the studied plasticizers showed good plasticizing effect, except for PEG 400 which initially showed good effect, but on storage the films became unstable (12). Whereas in the present study, the authors are focusing on screening different polyols as plasticizers at concentration of 10-20% w/w, except for maltitol studied at 20 and 30% w/w concentration.…”

“…Some polymers cannot be extruded without using plasticizers or drug at particular concentration in the formulation, since these polymers produce excessive torque between the screws when extrusion is performed with polymer alone. For example, Repka and coworkers have reported that hydroxypropyl cellulose (HPC) films cannot be extruded without using plasticizers in the formulation (12). Plasticizers are typically ingredients with low molecular weight, either in liquid or solid state.…”

Off-line and on-line measurements of drug-loaded hot-melt extruded films using Raman spectroscopy

“…Several authors have successfully used HME technology to prepare various dosage forms including tablets, pellets, granules, and films (Zhang et al, 1992;Follonier et al, 1995;Aitken-Nichol et al, 1996;Repka et al, 1999;Young et al, 2002). HME may be used to disperse drugs in a given matrix at the molecular level, thus forming solid solutions.…”