Characterisation of Silicone Elastomer Vaginal Rings Containing HIV Microbicide TMC120 by Raman Spectroscopy

Silicone elastomer vaginal rings are currently being pursued as a controlled-release strategy for delivering microbicidal substances for the prevention of heterosexual transmission of HIV. Although it is well established that the distribution of drugs in delivery systems influences the release characteristics, in practice the distribution is often difficult to quantify in-situ. Therefore, the aim of this work was to determine whether Raman spectroscopy might provide a rapid, non-contact means of measuring the concentrations of the lead candidate HIV microbicide TMC120 in a silicone elastomer reservoir-type vaginal ring. Vaginal rings loaded with TMC120 were manufactured and sectioned before either Raman mapping an entire ring cross-section (100 µm resolution) or running line scans at appropriate time intervals up to 30 h after manufacture. The results demonstrated that detectable amounts of TMC120, above the silicone elastomer saturation concentration, could be detected up to 1 mm into the sheath, presumably as a consequence of permeation and subsequent reprecipitation. The extent of permeation was found to be similar in rings manufactured at 25 and 80°C.

Teachers and pupils: educational experiences and school based responses to the conflict in Northern Ireland

This article describes a study which examined (a) the impact of the political conflict on teachers' and ppils' experiences of education in Northern Ireland and (b) the impact of curricular-based interventions designed to support the ppils and reduce prejudice. The focus of the second part of the article is on the prejudice reduction initiatives identified. A total of 44 staff and 78 pupils spread across 8 schools participated and both teachers' and ppils' perspectives were identified, the latter being an extremely important dimension which has rarely been addressed in previous studies of this area. The findings, which highlight the complexity of the impact of the political conflict, are considered to have both practical and theoretical implications for prejudice reduction programs.