Modeling of drug release, erosion and diffusion fronts movement in high viscosity HPMC matrices containing a cellulolytic enzyme.

A formerly developed mathematical model describing drug release from hydrophilic matrices (HMs) took into account resistance to drug release given by its dissolution and by the presence of a growing gel layer. Such a model was applied to previously reported release data obtained from HMs made of hydroxypropyl methylcellulose (HPMC), where acetaminophen was used as model drug and a cellulolytic product was added as "active" excipient to attain zero-order release kinetics. The Levich theory applied to acetaminophen intrinsic dissolution rate (IDR) data highlighted the suitability of such a drug for modeling purposes, given its good surface wettability.

The Key Role of Wettability and Boundary Layer in Dissolution Rate Test.

Background/objectives: The present work proposes a mathematical model able to describe the dissolution of poly-disperse drug spherical particles in a solution (Dissolution Rate Test-DRT). DRT is a pivotal test performed in the pharmaceutical field to qualitatively assess drug bioavailability.

Methods: The proposed mathematical model relies on the key hallmarks of DRT, such as particle size distribution, solubility, wettability, hydrodynamic conditions in the dissolving liquid of finite dimensions, and possible re-crystallization during the dissolution process.

Supramolecular eutectogel as new oral paediatric delivery system to enhance benznidazole bioavailability.

Benznidazole (BNZ) serves as the primary drug for treating Chagas Disease and is listed in the WHO Model List of Essential Medicines for Children. Herein, a new child-friendly oral BNZ delivery platform is developed in the form of supramolecular eutectogels (EGs). EGs address BNZ's poor oral bioavailability and provide a flexible twice-daily dose in stick-pack format.

Ionic Strength Impacts the Physical Properties of Agarose Hydrogels.

Agarose is a natural polysaccharide known for its ability to form thermoreversible hydrogels. While the effects of curing temperature and polysaccharide concentration on mechanical properties have been discussed in the literature, the role of ionic strength has been less studied. In the present manuscript, we investigate the effects of supporting salt concentration and the role of cation (i.

Mucus Structure, Viscoelastic Properties, and Composition in Chronic Respiratory Diseases.

The respiratory mucus, a viscoelastic gel, effectuates a primary line of the airway defense when operated by the mucociliary clearance. In chronic respiratory diseases (CRDs), such as asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF), the mucus is overproduced and its solid content augments, changing its structure and viscoelastic properties and determining a derangement of essential defense mechanisms against opportunistic microbial (virus and bacteria) pathogens. This ensues in damaging of the airways, leading to a vicious cycle of obstruction and infection responsible for the harsh clinical evolution of these CRDs.