Chemical study and anti-inflammatory, analgesic and antioxidant activities of the leaves of Aristotelia chilensis (Mol.) Stuntz, Elaeocarpaceae.

Objectives: Aristotelia chilensis leaves (Elaeocarpaceae) are used in Chilean folk medicine to treat pain and inflammation. A bioguided study was carried out on serial extracts (hexane, dichloromethane, methanol, aqueous extract (INFU) and a crude mixture of alkaloids (ALK-MIX). All extracts were evaluated for (1) topical administration against both arachidonic acid and 12-deoxyphorbol-13-decanoate (TPA)-induced inflammation in mice and (2) per-os administration against inflammation by λ-carrageenan-induced paw oedema in guinea-pigs and (3) topical analgesia in tail flick and formalin models and per-os writhing test in mice.

Study of dissolution behavior of matrices tablets based on alginate-gelatin mixtures as prolonged diltiazem hydrochloride release systems.

The aim of this work was to develop prolonged diltiazem hydrochloride release matrices based on alginate-gelatin mixtures and establish the drug release mechanism. The erosion, swelling, and dissolution behavior of the tablets in different medium were evaluated. The different polyelectrolyte behavior and gel strength between type A Gelatin and type B Gelatin would explain the different swelling, erosion and dissolution behavior in the media with sudden pH change.

Comparative studies on polyelectrolyte complexes and mixtures of chitosan-alginate and chitosan-carrageenan as prolonged diltiazem clorhydrate release systems.

The aim of this work was to evaluate the possibility of using mixtures and/or polyelectrolyte complexes from both chitosan-alginate and chitosan-carrageenan as prolonged drug release systems. Different dissolution profiles were obtained by changing the polymer matrix system (chitosan-alginate or chitosan-carrageenan) and the method used to include these polymers into the formulation (physical mixture or polyelectrolyte complex). Drug dissolution profiles from the matrices have been discussed by considering the swelling behavior of the polymers used.