BACKGROUND Visual assessment of cerebrospinal fluid (CSF) for xanthochromia (yellow color) is practiced by the majority of laboratories worldwide as a means of diagnosing intracranical bleeds. METHODS Colorimetric and spectrophotometric analysis of CSF samples for recognizing the presence of bilirubin either in low concentrations or in the presence of hemolysed blood. RESULTS The experiment...

LLE Review, Volume 73 59 Ever since cholesteric liquid crystals (CLC’s) were discovered in 1888,1 CLC colors have been noted for their qualitative vividness and luminosity;2 however, there have been few quantitative colorimetric studies examining CLC’s as colorants. We will describe how CLC’s produce color, what colorimetric studies have been done on them, and how we have extended and improved ...

some physical attributes of two common types of iranian garlic cloves (white and pink) were identified and compared. a machine vision system was used to determine three di-mensions and both major and minor projected areas of garlic cloves at a moisture content of 42.4% w. b. the geometric mean diameter and sphericity were calculated, as well as the unit mass and volume of cloves were measured. ...

Episulfides were determined by a simple colorimetric assay using 4-(p-nitrobenzyl)-pyridine, which has been used previously for the detection and analysis of epoxides, organophosphates, and other alkylating agents. With episulfides, absorbance was directly proportional to concentration up to an absorbance of at least 1.0. No interference was observed with a variety of non-episulfide sulfur-cont...

The design, synthesis and physical evaluation of 1, a visible colorimetric 'naked eye' pyridyl based bis-amidothiourea sensor for anions, is described. This charge neutral sensor gives rise to significant changes in the absorption spectra upon interactions with several important biological anions such as AMP and ADP in 4:1 DMSO-H(2)O solution, while ATP was not detected. These colorimetric chan...

In order to find a fast, high efficient determination method of Organophosphorus Pesticides (OPPs) residue because OPPs widely used in crops pest control fields in China are causing fearful risks for environment as well as animals and human health, traditional and advanced determination methods were discussed in the study. Based on the spectrum analysis technology combined colorimetric OPPs res...

Biosensors are analytical devices that have found a variety of applications in medical diagnostics, food quality control, environmental monitoring and biodefense. In recent years, functional nucleic acids, such as aptamers and nucleic acid enzymes, have shown great potential in biosensor development due to their excellent ability in target recognition and catalysis. Deoxyribozymes (or DNAzymes)...

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...

Isoniazid is an important antibiotic, which is widely used to treat tuberculosis. This study presents a colorimetric method for the determination of Isoniazid based on localized surface plasmon resonance (LSPR) property of gold nanoparticles. An LSPR band is produced by reducing gold ions in solution using Isoniazid as the reducing agent. Influences of the following relevant variables were exam...

Two radiochemical (Irosorb 59 and Res-O-Mat Fc), a mechanized (DSA 560) and several manual colorimetric procedures (test combination of Roche, Merck and Haury) for the determination of the total iron binding capacity were compared with the transferrin-binding capacity (immunoprecipitation). Whereas all methods show a satisfactory correlation with the transferrin concentration, most colorimetric...