We developed an assay to determine the mobilities (diffusion coefficients) of HIV and anti-HIV molecules in delivery vehicles. The assay tracks 1-dimensional diffusion of UV-photoactivateable, caged fluorescent particles over biologically relevant distances of ~100-500 microns.
An ultraviolet light source uncages a defined region of fluorophore-labeled gel (the delivery vehicle). The resulting fluorescence is measured over time and space with a microarray scanner. The diffusion coefficient is computed by analyzing the temporal and spatial distribution of the photoactivated fluorophore compared to its original uncaged region.
This technique can be expanded to fluorophore-labeled virus-like particles (VLPs) and microbicide-like molecules (MLMs) to model the diffusion of HIV and anti-HIV molecules in delivery vehicles.
