Described herein is a degradable linking agent of formula Photo1-LG-Photo2, wherein Photo1 and Photo2 independently represent at least one photoreactive group and LG represents a linking group comprising one or more silicon atoms or one or more phosphorous atoms. The degradable linking agent includes a covalent linkage between at least one photoreactive group and the linking group, wherein the covalent linkage between at least one photoreactive group and the linking group is interrupted by at least one heteroatom. A method for coating a support surface with the degradable linking agent, coated support surfaces and medical devices are also described.