Patent ID: 8735167

Claim:
A method of amplified fluorescence quenching comprising: (a) providing a plurality of masked photosensitizers, each masked photosensitizer having a masking group bonded to a quenching photosensitizer through a releasable covalent bond which disrupts the conjugation of the quenching photosensitizer; (b) providing a fluorophor in quenching proximity to a first masked photosensitizer; (c) providing a reaction photosensitizer in releasing proximity to a masked photosensitizer, exciting the reaction photosensitizer with photoradiation, whereby the reaction photosensitizer releases the masking group from a masked photosensitizer, forming an unmasked photosensitizer; (d) exciting the unmasked photosensitizer with photoradiation, whereby this excited unmasked sensitizer induces fragmentation in a masked photosensitizer, inducing release of the masking group from the first masked photosensitizer, producing a quenching photosensitizer which (1) reduces the fluorescence of the fluorophor and (2) induces the release of the masking group from another masked photosensitizer; and (e) repeating step (d).