“…Most of these methods can be categorized into two groups: (i) those based on photochemically generated radicals using aryl azides [15,16], benzophenones [17][18][19], anthraquinones [20], photosensitive amino acids [21], dye bleaching [22], or photocatalytic reactions [23] and (ii) those based on reactive functional groups protected by a photocleavable group, such as caged amines [24,25], caged carboxy groups [26,27], caged oximes [28], caged biotins [29], and caged aldehydes [30]. The former category of methods is superior in terms of its capability to immobilize a wide range of ligands.…”