1. An in vitro study evaluated the release of wetting agents from Group IV contact lenses. Lenses were soaked overnight in either renu fresh multi-purpose or OPTI-FREE Express. Lenses were rinsed with phosphate buffered saline at a rate approximating tear film secretions for an eight-hour period. At designated times, surface tension (dynes/cm) of wetting agents rinsed from the lens was calculated using saline as the control and compared to the surface tension for the multi-purpose solutions. The results are an indication that renu fresh multi-purpose solution remains present on lens surfaces longer than competitive products.
