Patent ID: 8808668
Filing Date: 2014-08-19
Classification: A61K

Abstract:
1. A method of measuring x-ray attenuation of a sample with an x-ray attenuating compound, comprising a) adding the x-ray attenuating compound to the sample, the sample having an external stimulus in an amount sufficient to modulate the x-ray attenuating compound from a first conformational state to a second conformational state; b) exposing the x-ray attenuating compound to an energy source; and c) calculating the amount of the external stimulus present in the sample by measuring a difference in x-ray attenuation of the energy source provided by the first conformational state and the second conformational state of the x-ray attenuating molecule, wherein the x-ray attenuating compound, comprises: a molecule having at least two conformational states; a first k-edge atom attached to the molecule at a first position, wherein the first k-edge atom is iodine; and a second k-edge atom attached to the molecule at a second position, wherein the molecule changes from a first conformational state to a second conformational state in response to an external stimulus, wherein a first interatom distance between the first k-edge atom and the second k-edge atom in the first conformational state is within a first harmonic error of 0 to about 0.2, and wherein a second interatom distance between the first k-edge atom and the second k-edge atom in the second conformational state is within a second harmonic error with a remainder of about 0.8 to 0.99.