CONICET | Buscador de Institutos y Recursos Humanos

Fluid injection systems for in-situ formation of polymer matrices represent an attractive alternative for the development of drug delivery systems in the field of human medicine and animal. In particular, the utilization of polymer solutions capable of gelling in situ at temperatures close to the physiological, designed to assure long residence times and control drug release. Thus, the development of these applications in veterinary field has become of increasing commercial interest, generating intensive R&D work. The global market for advanced drug delivery systems amounted to $134.3 billion in 2008, and was forecast to grow to $139 billion in 2009. The estimate is $196.4 billion by 2014, for an annual growth rate of 7.2% in the 5-year period. The estimated sales for sustained-release systems are $ 36.1 billion in 2009 and $ 45.8 billion by 2014 for an annual growth rate of 4.9% (1). The poloxamers are thermosensitive materials more frequently used for their advantages such like easy availability, simple method for preparation of the gel, and good compatibility with various drugs and pharmaceutical excipients. Poloxamer gels are widely used in the pharmaceutical field, being generally like considered safe excipients (2). It is well known that poloxamer solutions present the reverse thermal gelation phenomenon, behaving as solution at low temperature and gelling as temperature increases (3, 4). The aim of the present work was to explore the potential of the combination of poloxamer 407, poloxamer 188, and carrageenan for their application as an injectable depot system for drug release to veterinary use. Progesterone was used as a model drug. The profiles of release and erosion in vitro were evaluated. It was also determined gelation temperature and gel strength of poloxamer gels.