Fluorescence Ratio Imaging
نویسندگان
چکیده
In this paper, the properties of the mean and variance of three estimators of the ratio between two random variables x, y are discussed. Given n samples of x and y we can construct two different estimators. One is biased and the other is asymptotically unbiased. Using the noise characteristics (variance, covariance) a third, unbiased estimator can be constructed. 1. Introduction In fluorescence microscopy, ratio imaging is applied in a number of applications. In ratio labeling, the ratio between the intensities of different fluorochromes is used to expand the number of labels for an in situ hybridization procedure [1]. This number is normally restricted by the number of fluorochromes that can be spectrally separated by fluorescence microscopy. Fluorescence ratio imaging is also used to measure spatial and temporal differences in ion concentrations within a single cell. This is achieved by using fluorochromes whose excitation or emission spectrum change as function of the Ca ++ or pH concentration [2]. In a third application of ratio imaging, known as Comparative Genome Hybridization (CGH) [3,4], one tries to estimate the DNA sequence copy number as a function of the chromosomal location. This is achieved by measuring the ratio between " tumor " DNA and " normal " DNA to detect gene amplifications and deletions.
منابع مشابه
Comparative Studies of High Contrast Fluorescence Imaging Efficiency of Silica-coated CdSe Quantum Dots with Green and Red Emission
Herein we report the possibility of using green and red emitting silica-coated cadmium selenide (CdSe) quantum dots (QDs) for remarkable stem and cancer cellular imaging, efficient cellular uptake and fluorescence imaging of semi and ultra-thin sections of tumor for in vivo tumor targeted imaging applications. The comparative studies of high contrast cellular imaging behaviours of the silica-co...
متن کاملA Thin Layer Imaging with the Total Internal Reflection Fluorescence Microscopy
Total internal reflection fluorescence microscopy (TIRFM) is an optical technique that allows imaging of a thin layer of the sample with a thickness of about 100-200 nm. It is used in science of cell biology to study cellular processes, especially near the membranes of living cells. This method is based on the total internal reflection phenomenon, where the evanescent wave is generated in the l...
متن کاملEvaluation of Reflection Optical Imaging Characteristics Using Fluorescence with Near Infrared Wavelength at Different Depths of Tissue Equivalent Phantom
متن کامل
Excitation-and-collection geometry insensitive fluorescence imaging of tissue-simulating turbid media.
We present an imaging technique for the correction of geometrical effects in fluorescence measurement of optically thick, turbid media such as human tissue. Specifically, we use the cross-polarization method to reject specular reflection and enhance the diffusive backscattering of polarized fluorescence excitation light from the turbid media. We correct the nonuniformity of the image field caus...
متن کاملThe Development of Fluorescence Imaging Systems for Clinical Applications - Part I, Broad-Field Fluorescence Imaging
This article proposed a novel classification on fluorescence imaging for clinical applications, and presented a camera-based instrument to verify the functions by an animal mode. The imaging technologies of fluorescence currently are developed in biological medicine included broad-field fluorescence imaging, point-probe fluorescence imaging, and cross-sectional endoluminal fluorescence imaging ...
متن کاملSpectral Separation of Quantum Dots within Tissue Equivalent Phantom Using Linear Unmixing Methods in Multispectral Fluorescence Reflectance Imaging
Introduction Non-invasive Fluorescent Reflectance Imaging (FRI) is used for accessing physiological and molecular processes in biological media. The aim of this article is to separate the overlapping emission spectra of quantum dots within tissue-equivalent phantom using SVD, Jacobi SVD, and NMF methods in the FRI mode. Materials and Methods In this article, a tissue-like phantom and an optical...
متن کامل