The popular colorimetric assay for urinary 5-hydroxyindole-3-acetic acid based on the reaction with 1-nitroso-2-naphthol has been criticized for lack of specificity. Goldenberg (Clin. Chem. 19: 38-44, 1973) proposed a modification of this method, in which 2-mercaptoethanol is used to discharge unwanted chromophores. We compared results by both the unmodified and modified colorimetric methods wi...

Rapid and convenient biosensing platforms could be beneficial to timely diagnosis and treatment of diseases in virtually any care settings. Sandwich immunoassays, the most commonly used methods for protein detection, often rely on expensive tags such as enzyme and tedious wash and incubation procedures operated by skilled labor. In this report, we revolutionized traditional sandwich immunoassay...

A new nonlinear dimensionality reduction method for multi-spectral images was presented to solve the problem brought by high dimensionality of multi-spectral images during color reproduction. Firstly, according to the characteristics of human visual system, the CIE standard observer color matching functions were weighted to the source spectral reflectance and then a principal component analysis...

A general method has been developed which allows crosslinks to be produced between proteins and single-stranded DNA. Such single-stranded DNA protein complexes have been tested for blot hybridization using two colorimetrically detectable enzymes, namely peroxidase and alkaline phosphatase, as the protein moiety of the probe. After hybridization and incubation with a substrate solution sequences...

An inexpensive, rapid, and simple colorimetric test for detection of bacteriuria is described. This test does not require bacterial growth and has the marked advantage of being able to quantify bacteria, even when the organisms are present in the urine of bacteriuric patients who are being treated with antibiotics. The test is carried out with 1 ml of urine, which is processed through a 10-mm-d...

This study demonstrates the use of phosphor-screen autoradiography as a means of measuring cell adhesion and cell expansion on polymer surfaces. The method has particular merit in cases where a specific substrate may be opaque or biochemically incompatible with colorimetric assay methodologies. With the phosphor-screen autoradiography method, there was a linear relationship between cell number ...

Abstract: The colorimetric organization of RGB color images is analyzed through the computation of algorithms which can characterize fractal organizations in the support and population of their three-dimensional color histogram. These algorithms have shown that complex organizations across scales exist in the colorimetric domain for natural images with often non-integer fractal dimension over a...

There is an urgent need to build digital image databases with adequate colorimetric accuracy for museums, achieves and libraries. Traditional colorimetric imaging suffers from the possibilities of metameric problem, while spectral imaging can facilitate accurate tristimulus estimation and possibilities for spectral reconstruction of each pixel. Spectral image archives can be used to render accu...