A method of preparing a substrate with a composition comprising (i) an organoborane initiator and (ii) a radical curable component disposed thereon includes the step of depositing the composition onto the substrate wherein at least one of (i) the organoborane initiator and (ii) the radical curable component is deposited onto the substrate in the form of a gradient pattern. An article comprises the substrate and the gradient pattern formed on the substrate. The gradient pattern is formed from a developed composition comprising the reaction product of (i) the organoborane initiator and (ii) the radical curable component. By forming the gradient pattern on the substrate, combinatorial and high-throughput methods of generating and testing the developed composition are possible, which enable characterization of the developed composition for various physical and chemical properties.