Evaluation Study of In-Situ Gel Using Catanionic Surfactant Mixtures

The present study described the gelation temperature, gelation time, viscosity study, pH, properties of thermosensitive gel prepared of poloxamer 407 and carbopol 934P which are not affected by the concentration of each component. i.e. addition of Drugs or reference catanionic mixture. The use of Catanionic drug-surfactant mixtures was proven to be an efficient novel method of obtaining sustained drug release from Insitu gels. The effects of changes in the pH and ionic strength on the catanionic aggregates was also investigated, and this method of sustaining the release was found to be quite resilient to variations in both. Although the phase behavior was somewhat affected, large micelles and vesicles were still readily found. The drug release was significantly sustained even under NaCl. Comparing the diffusion coefficients for drugs being released from gels with those for drugs from catanionic mixtures in gels revealed differences in the order of magnitude of 10 to 100. This means that the release of a drug can be extended over time, for example, from 30 minutes to 12 hours, potentially improving both the efficiency of the formulation and the patient compliance.