Reduction in scattering from a turbid medium by photo-bleaching
First Claim
1. A method for reducing elastic scattering from a sample comprising an analyte residing at a significant depth in the sample and a non-uniformly distributed photo-bleachable substance, the method comprising:
- photo-bleaching the non-uniformly distributed photo-bleachable substance in the sample to induce a reduction in elastic scattering in the sample;
generating analyte spectra from inelastic scattering from the sample, wherein some or all of the analyte resides at a depth in the sample greater than an effective elastic scattering length of the sample, wherein the effective elastic scattering length is 1/us'"'"', wherein us'"'"' is an isotropic scattering coefficient of the sample, and wherein the inelastic scattering is relatively weak in relation to the elastic scattering; and
collecting the analyte spectra, wherein a sufficient amount of the analyte resides at the depth in the sample greater than an effective elastic scattering length of the sample such that the collected analyte spectra has a higher signal to noise ratio than without photo-bleaching.
3 Assignments
0 Petitions
Accused Products
Abstract
A method is proposed whereby photo-bleaching is used not only to change the absorption and fluorescence of a sample but is also employed to change its scattering characteristics. When the compounds which are bleached are contained in regions wherein the real part of the index of refraction is greater than or equal to the average index of the medium, the bleaching will result in reduction in the scattering at wavelengths longer than the wavelength of the bleaching source. This reduction can be useful in measuring the concentration of analytes located at significant depths within turbid media.
-
Citations
9 Claims
-
1. A method for reducing elastic scattering from a sample comprising an analyte residing at a significant depth in the sample and a non-uniformly distributed photo-bleachable substance, the method comprising:
-
photo-bleaching the non-uniformly distributed photo-bleachable substance in the sample to induce a reduction in elastic scattering in the sample; generating analyte spectra from inelastic scattering from the sample, wherein some or all of the analyte resides at a depth in the sample greater than an effective elastic scattering length of the sample, wherein the effective elastic scattering length is 1/us'"'"', wherein us'"'"' is an isotropic scattering coefficient of the sample, and wherein the inelastic scattering is relatively weak in relation to the elastic scattering; and collecting the analyte spectra, wherein a sufficient amount of the analyte resides at the depth in the sample greater than an effective elastic scattering length of the sample such that the collected analyte spectra has a higher signal to noise ratio than without photo-bleaching. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
Specification