Patent ID: 8133474

Claim:
A method for determining an analyte, comprising: providing a MRI or optical agent having the formula, wherein: A is a group comprising an aryl group, optionally substituted; B is a chelator group comprising at least one aromatic heterocycle; X 1 and X 2 can be the same or different and each is a heteroatom; L 1 and L 2 can be the same or different and each is a group comprising an alkyl or heteroalkyl group, optionally substituted; and Q 1 and Q 2 can be the same or different and each is a group comprising a binding moiety for an analyte; exposing the agent to a sample suspected of containing an analyte, wherein the agent interacts with the analyte, if present, to generate an analyte-bound MRI signal or optical signal that is shifted relative to the MRI signal or optical signal absent the analyte; and determining the shift in the MRI signal or an optical signal of the agent, or lack thereof, thereby determining the presence and/or amount of the analyte in the sample.